honors college thesis
TRANSCRIPT
USING JOB’S METHOD TO DETERMINE THE STOICHIOMETRIC RATIO OF A
METAL-AMINOPOLYCARBOXYLATE COMPLEX IN A NON-AQUEOUS
MEDIUM
______________________
A THESIS
Presented to the
Honors College at Southern University
Baton Rouge, Louisiana
______________________
In Partial Fulfillment of the Requirements for the
Honors College Degree
______________________
By
Nsombi Jahiare Roberts
May 2016
ii
Honors College
Southern University Baton Rouge, Louisiana
CERTIFICATE OF APPROVAL
____________________
HONORS THESIS
_____________________
This is to certify that the Honors Thesis of Nsombi Jahiare Roberts
has been approved by the examining committee for the thesis requirement for the Honors College degree in Chemistry
_________________________________________ Scott A. Wicker, Ph.D
Research Advisor
_________________________________________ Joyce W. O'Rourke, Ph.D
Chairman, Honors Advisory Committee
_________________________________________ Diola Bagayoko, Ph.D Dean, Honors College
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ABSTRACT
USING JOB’S METHOD TO DETERMINE THE STOICHIOMETRIC RATIO OF A
METAL-AMINOPOLYCARBOXYLATE COMPLEX IN A NON-AQUEOUS
MEDIUM
Name: Roberts, Nsombi Jahiare
Southern University and A&M College
Advisor: Dr. Scott A. Wicker
The increasing world population has led to a rapid increase in pollution. The
increasing cost of pollutant removal has led the world to turn to producing newer, cheaper,
and safer methods. There is a need for a sequestering agent that has effectiveness in
removing heavy metals from solutions, has minimum health effect, and is cost efficient.
This study sets to utilize an aminopolycarboxylic acid to develop a method that is effective
in removing pollutants from aqueous and non-aqueous mediums. The titrimetric methods
of analysis were used to develop a method that is cheap and safe for removing pollutants
such as toxic metals from non-aqueous and aqueous mediums. The physiochemical
properties of the aminopolycarboxylic acid observed were used to develop a method that
is cheap and safe for removing pollutants such as toxic metals from non-aqueous solutions.
3, 3’, 3”-Nitrilotripropionic acid (NTP) was synthesized from acrylic acid and β-Alanine
using Michael Addition and coordinated to a metal complex in a non-aqueous solution.
The method of continuous variation was used to find the stoichiometric ratio of the metal
complex.
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DEDICATION
I would like to dedicate my work to my mother, Turkessa. Without her strength and faith
in my abilities, I would not be able to achieve nearly as much as I have. I would also like
to dedicate my work to my brothers, Desmond and LaDarius, and my sister, Diamond,
who I always strive to set the example for.
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ACKNOWLEDGMENTS
I would like to thank my advisor Dr. Scott A. Wicker for the time, knowledge, and
guidance he has provided in conjunction with this thesis. I would also like to thank Dr.
Conrad Jones for the knowledge he provided me regarding Infrared Spectrometry and Dr.
Weihua Wang for the knowledge she provided me regarding Michael Addition.
I would also like to express my appreciation to a professor outside the Chemistry
department, Dr. Eduardo Martinez-Ceballos for providing me with training and use of the
light microscope in the Health Research Center.
I would like to thank the members of my 2015-2016 CHEM 422/423 Chemical
Research classes for the necessary edits to my thesis.
A special thanks goes to the Sorors of Zeta Phi Beta Sorority, Incorporated for
providing me with scholarships to lessen my financial needs and focus more of my time of
conducting my research.
I would also like to thank the Dolores Margaret Richard Spikes Honors College for
allowing me the opportunity to research, write, and defend my Honors thesis.
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PREFACE
The research conducted in this thesis was done for the partial fulfillment of the
requirements for the Bachelor of Science Honors Degree in Chemistry at Southern
University and A&M College. It was also conducted to fulfill the requirements for the
classes Chemical Research CHEM 422 and Chemical Research CHEM 423.
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TABLE OF CONTENTS APPROVAL ....................................................................................................................... ii
ABSTRACT ....................................................................................................................... iii
DEDICATION ................................................................................................................... iv
ACKNOWLEDGMENTS ...................................................................................................v
PREFACE .......................................................................................................................... vi
LIST OF ILLUSTRATIONS ...............................................................................................x
LIST OF TABLES ............................................................................................................ xii
LIST OF ABBREVIATIONS AND NOTATIONS ........................................................ xiii
CHAPTER I: INTRODUCTION .........................................................................................1
1.1 The Problem .......................................................................................................1 1.2 Statement of the Problem ...................................................................................3 1.3 Importance of the Study .....................................................................................3 1.4 Specific Aims of the Study ................................................................................3
1.4.1 Specific Aim 1 ....................................................................................3 1.4.2 Specific Aim 2 ....................................................................................3
1.5 Literature Cited ..................................................................................................5
CHAPTER II: REVIEW OF LITERATURE ......................................................................6
2.1 Organic Chemistry .............................................................................................6 2.1.1 Aminopolycarboxylic acids ................................................................6 2.1.2 Geometry .............................................................................................7 2.1.3 Symmetry ............................................................................................7 2.1.4 Chelation .............................................................................................8 2.1.5 Retrosynthesis .....................................................................................9
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2.1.6 Michael addition ...............................................................................10 2.2 Analytical Chemistry .......................................................................................12
2.2.1 Acid-base chemistry ..........................................................................12 2.3 Inorganic Chemistry .........................................................................................12
2.3.1 Coordination chemistry .....................................................................12 2.3.2 Ultraviolet-Visual Spectrum .............................................................13
2.4 Literature Cited ........................................................................................................16
CHAPTER III: SYNTHESIS OF 3, 3’,3”-NITRILIOTRIPROPIONIC ACID ...............17
3.1 Introduction ......................................................................................................17 3.2 Experimental method .......................................................................................17
3.2.1 Materials ...........................................................................................17 3.2.2 Procedure ..........................................................................................18
3.2.2.1 Synthesis ...............................................................................18 3.2.2.2 Titration ................................................................................19
3.3 Results ..............................................................................................................19 3.4 Discussion ........................................................................................................19
3.4.1 Michael Addition ..............................................................................20 3.4.2 Solubility ...........................................................................................20 3.4.3 Titration .............................................................................................233.4.4 Symmetry ..........................................................................................27 3.4.5 Melting Point ....................................................................................28
3.5 Conclusion .......................................................................................................28 3.6 Literature Cited ................................................................................................29
CHAPTER IV: STOICHIOMETRIC RATIO OF NITRILOTRIPROPIONIC ACID TO
CUPRIC CHLORIDE IN A NON-AQUEOUS MEDIUM USING THE JOB’S
METHOD .........................................................................................................................30
4.1 Introduction ......................................................................................................30 4.2 Experimental method .......................................................................................30
4.2.1 Materials ...........................................................................................30 4.2.2 Procedure ..........................................................................................31
4.3 Results ..............................................................................................................32 4.4 Discussion ........................................................................................................33
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4.5 Conclusion .......................................................................................................38 4.6 Literature Cited ................................................................................................40
BIOGRAPHY ....................................................................................................................41
RESUME ...........................................................................................................................42
APPROVAL OF SCHOLARLY DISSEMINATION .......................................................44
x
LIST OF ILLUSTRATIONS
1. β-Alanine. Protonated amino group in blue. Deprotonated carboxyl group in red...….6
2. Example of an aminopolycarboxylic acid: ethylenediaminetetraacetic acid (EDTA).7
3. Symmetry of ammonia…………………………………………………………….......8
4. 2, 2’, 2”-Nitrilotriacetic acid………………………………………...…………..….....9
5. 3, 3’, 3”-Nitrilotripropionic acid………………………………………………..…......9
6. Retrosynthesis of NTP…………………………………………………………….....10
7. Reaction of diethyl malonate (michael donor) with cyclohexenone (michael acceptor)
to produce a new carbon-carbon bond and larger molecule……………...……….....11
8. Electromagnetic spectrum……………...……………………………………….........15
9. Color wheel with corresponding wavelength ranges…..………………………….....15
10. First step of Michael addition synthesis for NTP……………………...………….....21
11. Second step of Michael addition synthesis for NTP………………………...…….....22
12. Recrystallization of NTP……………….............………………………………….....23
13. Titration of NTP in NaOH………………………………………......…………….....23
14. Potentiometric analysis of NTP in an aqueous medium……….………………….....25
15. Predicted species of NTP in an aqueous medium........................................................26
16. NTP speciation concentration diagram........................................................................26
17. 3-D ammonia molecule……………………...............…………………………….....27
18. Varying ratios (M:L) of 2mM Copper (II) chloride and 2mM NTP in DMSO. From left
to right: 1:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9, 0:1.. ....................................….32
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19. Varying ratios (M:L) of 0.05M Copper (II) chloride and 0.05M NTP in DMSO. From
left to right: 1:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9, 0:1.....................................32
20. Spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO…...………….....33
21. Resonance structures of DMSO ……………………......…………...…………….....34
22. Copper (II) chloride in water and Copper (II) chloride in DMSO ………………......34
23. Spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO from 680 nm-800
nm………………………………...............................…………………………….....35
24. Spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO from 680 nm-900
nm ……………..........................................................................................……….....35
25. Spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO from 380 nm-480
nm ……………...………………...................................………………………….....36
26. Calibration curve of Copper (II) Chloride in DMSO …..……………………...….....36
27. Enhanced spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO at (from
top left to right to bottom left to right) metal to ligand ratios of 4:6, 3:7, 2:8, and
1:9……………………...……...........................................................….............….....37
28. Spectrum of 1:9 Metal to Ligand Ratio of 0.05M NTP and 0.05M Copper (II) Chloride
in DMSO......................................................................................................................38
29. Spectrochemical series.................................................................................................38
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LIST OF TABLES
1. Experimental NTP protonation constants comparison to Govender and Wicker........25
2. Phase Diagram for NTP with Copper (II) Chloride in DMSO....................................31
xiii
LIST OF ABBREVIATIONS AND NOTATIONS
NTP 3, 3’, 3”-Nitrilotripropionic acid
NTA 2, 2’, 2”-Nitrilotriacetic acid
DMSO dimethyl sulfoxide
1
CHAPTER I: INTRODUCTION
1.1 The Problem
First world countries are plagued with high density industrialized areas that produce
large amounts of pollutants on a daily basis. This is not to be confused with the general
term for unwanted remains and byproducts or waste that these corporations expel. A
pollutant is described as a waste material that pollutes or contaminates the environment.
Pollution is categorized into several different groups: air, thermal, soil, radioactive, and
water.
Water pollution occurs when pollutants spread from a source to the environment,
leaving natural resources such as water systems fouled by human existence. Contaminated
water sources can contain various dense, potentially toxic metals or heavy metals that are
a danger to the human condition. The heavy metals of major health concern are cadmium,
mercury, lead and arsenic.1 Other heavy metals that are less toxic are manganese,
chromium, cobalt, nickel, copper, zinc, selenium, silver, antimony and thallium. These
heavy metals can only be removed through transformation from one oxidation state or
organic complex to another.2
As of 2016, the major environmental issue at hand in the United States is the drinking
water contamination crisis in Flint, Michigan. The city of Flint is currently in a federal state
of emergency which allows the federal government to take the forefront on handling the
issue at hand. The drinking water for the city of Flint was switched from the same
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source used by the city of Detroit to the Flint River, a previous back up source. The city
originally did not use the Flint River as a primary source because the overall cost for the
treatment of that water was more expensive than water from Lake Huron, Detroit’s current
water source.3
The water from the Flint River was contaminated by lead that leached into the water
system from outdated pipes. Leaching is described as the process of removing a soluble
mineral or chemical from a solid source with a liquid either naturally or through forced
means.4 The improper treatment of the water and the ineffective methods used to remove
the leached lead posed a serious health risk to the citizens of Flint. Lead is the second most
hazardous metal according to the Priority List of the US Environmental Protection
Agency.5 News stations across the country displayed the unnatural discoloration of water
in the homes of dozens of Flint residents. Many children were found having highly elevated
levels of lead in their blood stream which translates to lead poisoning. Lead poisoning can
lead to “deficits in intellectual functioning, academic performance, problem solving skills,
motor skills, memory and executive functioning are consistently observed in lead-exposed
children, in addition to an increased likelihood of experiencing ADHD and having conduct
problems in childhood, and decreased brain volume in adulthood.”6
Green chemistry is “the utilization of a set of principles that reduces or eliminates the
use or generation of hazardous substances in the design, manufacture, and applications of
chemical products.”7 It is upon this foundation that purification systems were born. Water
purification methods are costly to the average citizen forced by their social economic status
to live in these nearly uninhabitable areas. The current green chemistry methods in place,
3
while less costly and efficient, employ an aminopolycarboxylic acid that is a suspected
carcinogenic to humans.8
1.2 Statement of the Problem
The increasing world population has led to a rapid increase in pollution. The
increasing cost of pollutant removal has led the world to turn to producing newer methods.2,
9 There is a need for a sequestering agent that has effectiveness in removing heavy metals
from solutions, has minimum health effect, and is cost efficient.
1.3 Importance of the Study
Pollutants in water systems and soils negatively affect the lifecycles of plants and
animals, ultimately affecting human life. Metal removal from aqueous and non-aqueous
solutions through the use of an aminopolycarboxylic acid can be a cheaper and more
efficient purification process.
1.4 Specific Aims of the Study
The purpose of this study is to develop a green chemistry method for removing
pollutants from aqueous or non-aqueous solvents. This study was based on two specific
aims:
1.4.1 Specific Aim 1:
Synthesis of 3, 3’, 3” – Nitrilotriproionic acid from β-Alanine and acrylic acid.
1.4.2 Specific Aim 2:
4
Coordination of synthesized 3, 3’, 3” – Nitrilotriproionic acid to Cupric chloride in a non-
aqueous medium using the Job’s Method
5
1.5 Literature Cited
1. Järup, L., Hazards of heavy metal contamination. British Medical Bulletin 2003, 68 (1), 167-182. 2. Carlos Garbisu, I. A., Phytoextraction: a cost-effective plant-based technology for the removal of metals from the environment. Bioresource Technology 2001, 77 (3), 229-236. 3. Cavanaugh, P. Analysis of the Flint River as a Permanent Water Supply for the City of Flint - July 2011; September 9, 2011, 2011; pp 1-15. 4. Leach. 5. Eriberto Vagner de Souza Freitas, C. W. A. d. N., The use of NTA for lead phytoextraction from soil from a battery recycling site. Journal of Hazardous Materials 2009, 171 (1-3), 833-837. 6. Kathryn M. Barker, F. Q. Lead poisoning: Sources of exposure, health effects and policy implications. http://journalistsresource.org/studies/society/public-health/lead-poisoning-exposure-health-policy) (accessed 12 February 2016). 7. Warner, P. A. J., Green Chemistry: Theory and Practice. Oxford University Press: New York, 2000; p 152. 8. Opinion on trisodium nitrilotriacetate (NTA). http://ec.europa.eu/health/scientific_committees/consumer_safety/docs/sccs_o_046.pdf (accessed 10 February 16). 9. Barakat, M. A., New trends in removing heavy metals from industrial wastewater. Arabian Journal of Chemistry 2011, 4 (4), 361-377.
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CHAPTER II: REVIEW OF LITERATURE
2.1. Organic Chemistry
2.1.1. Aminopolycarboxylic acids
An aminopolycarboxylic acid is a compound containing one or more amino groups
connected through carbon atoms to two or more carboxyl groups. The amino functional
group consists of a nitrogen atom connected to either hydrogen atoms or hydrocarbon
groups. The carboxyl functional group is comprised of a carbon bonded to an oxygen atom
through a sigma and pi bond and a hydroxyl molecule bonded by a sigma bond. While
similar to an amino acid, aminopolycarboxylic acids do not form peptide bonds with each
other. A peptide bond forms when the carboxyl group of an amino acid reacts with the
amino group of another amino acid and also produces a water molecule.
Figure 1. β-Alanine. Protonated amino group in blue. Deprotonated carboxyl group in red.
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Figure 2. Example of an aminopolycarboxylic acid: ethylenediaminetetraacetic acid
(EDTA)
2.1.2. Geometry
The aminopolycarboxylic acid 2, 2’, 2”-Nitrilotriacetic acid (NTA) has a molecular
and electronic geometry similar to ammonia around the nitrogen atoms. Ammonia,
NH#,has a tetrahedral electron pair geometry that produces a trigonal pyramidal molecular
geometry. The carbon of the carboxyl group, while traditionally holding a tetrahedral
molecular geometry, produces a trigonal planar molecular and electron geometry when
paired with an oxygen atom and hydroxyl group. The electron donor groups or lone pairs
on the nitrogen and deprotonated carboxyl groups of aminopolycarboxylic acids are the
sites used for chelation.
2.1.3. Symmetry
All molecules can be described using symmetry elements such as mirror planes,
axes of rotation, and inversion centers. A symmetry operation describes the actual
reflection, rotation, or inversion. Ammonia has an identity element E (characteristic of all
molecules), two rotation or operations (C#andC#* both through nitrogen), and three mirror
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reflections. The identity element E has a 360° rotation about the z axis. The rotation C# has
three 120° rotations about the z axis and C#* is a variation of that in which two C# rotations
(total of 240°) gives a new rotation that looks the same as one C# rotation.
Figure 3. Symmetry of ammonia
2.1.4. Chelation
Chelation is defined as “The formation or presence of bonds (or other attractive
interactions) between two or more separate binding sites within the same ligand and a
single central atom.” A chelating agent is the substance or ligand used to form coordination
complexes with metal ions. NTA is a tetradentate ligand, which makes it excellent for
purification, however it is a possible carcinogenic to man. 3, 3’, 3”-Nitrilotripropionic acid
(NTP) is similar to NTA but is a weaker chelating agent that differs by an additional – CH*
on each leg of the molecule.
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The current studies being done with chelating aminopolycarboxylic acids is chelate
assisted phytoextraction.3 Phytoextraction is a sub-process of phytoremediation, the
treatment of environmental problems through the use of plants, in which plants are used to
remove compounds such as heavy metals from soil or water. The chelating properties of
aminopolycarboxylic acids make them ideal for the removal of metals from contaminated
waters1, yet there removal properties in non-aqueous mediums is unknown. NTP has a low
coordination capacity compared to NTA.2
Figure 4. 2, 2’, 2”-Nitrilotriacetic acid Figure 5. 3, 3’, 3”-Nitrilotripropionic acid
2.1.5. Retrosynthesis
The design of the synthesis requires consideration of production cost and the
number of steps associated with the desired product. In organic chemistry, this design is
called a retrosynthesis. Retrosynthesis is the process of working backwards from a product
to produce plausible reactants for an organic synthesis. Previous experiments for the
synthesis of 3, 3’, 3”-Nitrilotripropionic acid were conducted using ammonium hydroxide
solution and acrylic acid.4 If beginning with NTP, the removal of all three acrylic acid
groups leaves only ammonia. However, if only two acrylic acid groups are removed, a new
10
plausible starting reagent is formed for this synthesis. Research has shown that the current
production of NTP from acrylic acid and ammonium hydroxide produces low yields.
Figure 6: Retrosynthesis of NTP
2.1.6. Michael addition
Michael addition, also known as conjugate addition5, which involves a Michael
donor (a nucleophile) and a Michael acceptor (an electrophile). The nucleophile is an
electron pair donor while the electrophile is an electron pair acceptor. The addition is
typically used by organic chemists to increase the number of carbons in a molecule. The
nucleophile reacts with the vinyl functional group of the electrophile to create a larger
molecule. The addition of carbons to nitrogen is most effectively done using the Michael
addition.6
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Figure 7. Reaction of diethyl malonate (michael donor) with cyclohexenone (michael
acceptor) to produce a new carbon-carbon bond and larger molecule7
There are two different types of Michael additions: 1,2 and 1,4. The 1,2-Michael
addition corresponds to a kinetically controlled reaction in which the most rapidly formed
product is called the kinetic product. The 1,4 Michael addition is the thermodynamically
controlled reaction that has the most stable product. This is called the thermodynamic
product.
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2.2. Analytical Chemistry
2.2.1. Acid-base chemistry
The definitions for acids and bases have been vastly modified over the years to
account for new behaviors between molecules. There are three basic systems from which
an acid-base reaction can be categorized as: Arrhenius, Brønsted-Lowry, and Lewis.
An Arrhenius acid-base reaction is restricted to aqueous solutions in which an acid
yields hydrogen ions and a base yields hydroxide ions. A Brønsted-Lowry acid-base
reaction is restricted to molecules containing hydrogen ions in which an acid donates
hydrogen ions or protons to a base which accepts them.
The definition of a Lewis acid-base reaction, however, encompasses a broader list
of molecules. A Lewis acid is an electron pair acceptor and a Lewis base is an electron pair
donor. More specifically, these reactions deal with frontier orbitals in which the Highest
Unoccupied Molecular Orbital (HOMO) of the base and Lowest Unoccupied Molecular
Orbital (LUMO) of the acid interact.
2.3. Inorganic Chemistry
2.3.1. Coordination chemistry
Coordination compounds consists of a complex ion and one or more counter ions
held together by Coulombic attraction. The complex ion itself is held together by
coordinate covalent bonds, formed by the reactions of metal ions with groups of anions or
polar molecules. A coordinate covalent bond, also called a dative bond, is a covalent bond
in which one of the atoms donates both electrons and typically occurs as a Lewis acid-base
reaction between a metal and a ligand. A ligand is a molecule or ion that surrounds the
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metal in the complex ion. The metal ion acts as a Lewis acid while the ligand acts as a
Lewis base. The ligand must have at least one unshared pair of elections on the molecule
or ion. Within the ligand, the donor atom is the atom that is bound directly to the metal
atom.8
Depending on the number of donor atoms a ligand possesses, it is classified as a
monodentate (one donor atom), bidentate (two donor atoms), or polydentate (more than
two donor atoms). Bidentate and polydentate ligands are also called chelating agents
because of their ability to hold the metal ion like a claw. Most metals have two valence
numbers: primary or oxidation number and secondary or coordination number. The
coordination number refers to the number of donor atoms surrounding the central metal
atom in a complex ion.8 NTA and NTP both coordinate at the highly electronegative nitrogen
and oxygen atoms when deprotonated.9 NTP has been reported to complex with transition metals
such as nickel (II), cobalt (II), and copper(II).10
2.3.2. Ultraviolet-Visual Spectrum
Ultraviolet light and visible light causes electrons to promote from one molecular
orbital to another of higher energy. At ground state, electrons are in the lowest energy
molecular orbitals. An electron undergoes an electronic transition when a molecule absorbs
enough light energy to promote the electron to a higher orbital. The electron is then said to
be in an excited state. The electronic transition from a π bonding molecular orbital of low
energy to a π* anti-bonding molecular orbital of higher energy is called a π to π* transition.
Ultraviolet light ranges from 180 nm to 400 nm, visible light ranges from 400 nm
to 780 nm, and infrared goes beyond 780 nm. The electrons in the d orbitals of transition
14
metals absorb visible light and promote within the d orbital. Any compound that absorbs
visible light appears colored, but we do not see the color corresponding to the wavelength
that is observed, we see the complementary color. A color wheel is the best example of the
concept of complementary colors. If a wavelength of 470 nm is absorbed, blue light is
being absorbed. Yet, the color that is seen would be orange. Spectrophotometry can be
used to discover the composition of complex ions and solutions.
The Beer-Lambert Absorption Law is the linear relationship between absorbance
and concentration of an absorbing species at a specified wavelength. Through this equation,
several different variables can be found to identify characteristics of an unknown
compound. The equation is
A = εlc
where A is absorbance, ε is the molar absorptivity (or molar extinction coefficient) with
units of L mol-1 cm-1, l is the path length (in cm) of the sample or length of the cuvette in
which the sample is being held, and c is the concentration of the compound in the solution
in mol L-1.
15
Figure 8. Electromagnetic spectrum
Figure 9. Color wheel with corresponding wavelength ranges
16
2.4. Literature Cited
1. Eveliina Repo, J. K. W., Amit Bhatnagar, Ackmez Mudhoo, Mika Sillanpaa, Aminopolycarboxylic acid functionalized adsorbents for heavy metals removal from water. Water Research 2013, 47 (14), 4812-4832. 2. Araujo, M., Brito, F., Cecarello, I., Guilarte, C., Martinez, JD, Monsalve, G., Oliveri, V., Rodriguez, I. and Salazar, A., Solution studies of vanadium(IV) complexes with nitrilotriacetic acid (NTA) and other aminopolycarboxylic acids (NDAP, NDPA, and NTP). Journal of Coordination Chemistry 2009, 62 (1), 75-81. 3. Michael Evangelou, M. E., Andreas Schaeffer, Chelate assisted phytoextraction of heavy metals from soil. Effect, mechanism, toxicity, and fate of chelating agents. Chemosphere 2007, 68 (6), 989-1003. 4. Wicker, S. A. Development of a Green Soft Chemical Method for the Synthesis of Cathode Materials Utilized in Lithium-ion Energy Storage Technologies. Dissertation, Southern University and A & M College, Baton Rouge, Louisiana, 2011. 5. Brian D. Mather, K. V., Kevin M. Miller, Timothy E. Long, Michael addition reactions in macromolecular design for emerging technologies. Progress in Polymer Science 2006, 31 (5), 487-531. 6. Mohammad R. Saidi , Y. P. F. A., Highly Efficient Michael Addition Reaction of Amines Catalyzed by Silica-Supported Aluminum Chloride. Synthetic Communications 2009, 39 (6), 1109. 7. Mehta, A. Michael Addition. http://pharmaxchange.info/press/2011/04/michael-addition/ (accessed 20 August 2015). 8. Burdge, J., Coordination Chemistry. In Chemistry, 3rd ed.; McGraw-Hill Education: New York, 2013; pp 976-993. 9. N.I. Barnard, H. G. V., Novel synthetic method for cobalt complexes: Structural and kinetic study of [Co(nta)(py)(H2O)]. Inorganic Chemistry Communications 2012, 15, 40-42. 10. Govender, K. K. Theoretical studies of nitrilotriacetic acid and nitrilotripropionic acid geometries for estimation of the stability of metal complexes by Density Functional Theory. Dissertation, University of Pretoria, Pretoria, 2009.
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CHAPTER III: SYNTHESIS OF 3, 3’,3”-NITRILIOTRIPROPIONIC ACID
4.1 Introduction
Nitriliotripropionic acid is an amino acid derivative that when in salt form or fully
deprotonated, coordinates with metal cations. Previous research has shown that
nitriliotripropionic acid can be synthesized from acrylic acid and ammonium hydroxide in
moderate yields.1 It has also been stated that the moderate yields are due to the third step
of the synthesis being the rate limiting step.2 If the rate limiting step in the synthesis is the
third step, then the use of β-alanine will have no effect on the yield of nitriliotripropionic
acid. In this chapter, the synthesis of nitriliotripropionic acid from β-alanine and acrylic
acid will be discussed along with a theoretical predictions for other characteristics.
4.2 Experimental Method
4.2.1 Materials
Acros Organics acrylic acid, 99.5%, extra pure, stabilized. Sigma-Aldrich
Chemistry β-Alanine, 99% purity. Graduated cylinder, 50mL. Pyrex two-neck round
bottom flask, 250mL. Magnetic stirring bar, octahedral, 22mm in length, 8mm in width.
Analytical balance. Plastic weighing boat. Penny stopper, 19/22. Hot plate stirrer. Utility
clamp. Heating mantle. Variable autotransformer, 120V/140V. Vernier stainless steel
18
temperature probe. Vernier pH sensor. Vernier LabPro®. Computer with Vernier Logger
Pro 3 software. Distilled water. Ice bath. Büchner flask, 500mL. Büchner funnel, 4in
diameter. Rubber bung. Rubber vacuum hose. Aspirator attached to a sink. Filter paper 4in
diameter. Watch glass, 6in diameter. Fisher Science Education Ethyl alcohol, 95%,
denatured. Drying oven. Thermo Scientific melting point instrument. Test tubes (4).
Capillary tube. Sigma-Aldrich Chemistry dimethyl sulfoxide (DMSO), for UV-
spectroscopy, 99.8%. Sigma-Aldrich Sodium hydroxide solution, 10.0M. Sigma-Aldrich
Hydrochloric acid solution, 1 M. Volumetric flask (2), 250 mL. Vernier drop counter kit.
4.2.2 Procedure
4.2.2.1 Synthesis
Added 11.4532g of β-Alanine to a 250mL two-neck round bottom flask. Added
50mL of distilled water and a magnetic stirring bar to the flask. Placed flask on the stir
plate for five minutes until all β-Alanine dissolved. Used the pH probe, temperature probe,
Vernier LabPro®, and a computer with Vernier Logger Pro 3 software to record the pH
and temperature of the β-Alanine solution. Added 21mL of acrylic acid to the β-Alanine
solution then used the pH probe, temperature probe, Vernier LabPro®, and a computer
with Vernier Logger Pro 3 software to record the pH and temperature with the acrylic acid
addition. Placed flask in the heating mantle on top of the stir plate and connected the flask
to the autotransformer. Used a utility clamp attached to a ring stand to hold the flask in
place. Turned the autotransformer to 120V at 30% output and allowed the flask to heat for
66 hours between 70°C and 79.9°C but not over 80°C. The flask was taken off of the
heating mantle after 66 hours and placed in an ice bath for one hour to promote crystal
formation. The crystals were then put on a vacuum filtration apparatus to remove all of the
19
crystals from the flask. The crystals were then rinsed with ethanol and put on filter paper
on a watch glass to dry in a drying oven. Once the crystals were dried, they were placed
back into the round bottom flask, dissolved in distilled water, and heated for 30 minutes
between 70°C and 79.9°C. The flask was then taken off of the heating mantle and placed
in an ice bath for two hours to promote recrystallization. The reformed crystals were put
on a vacuum filtration apparatus to remove all of the crystals from the flask, rinsed with
ethanol, and put on filter paper on a watch glass to dry in a drying oven. Once the crystals
were dried, they were weighed. A melting point test and solubility tests in DMSO, sodium
hydroxide, and ethanol, and were conducted.
4.2.2.2 Titration
Measured 5.8436 g of synthesized NTP into a 250mL volumetric flask. Added
100mL of distilled water and placed on a hot plate until dissolved then filled the flask for
a 0.1M solution. Measured out 25 mL of 10.0M NaOH and made a 1.0M solution of NaOH
in a 250mL volumetric flask. Set up the LabPro, pH sensor, and drop counter for titration.
Added 4 mL of 1.0M HCl to 10mL of 0.1M NTP solution to decrease the pH to 1. Began
titration.
4.3 Results
The initial pH after the addition of acrylic acid was 3.94 at 22.6°C. The pH of an
aqueous solution of NTP was found to be 3.03. The total amount of NTP collected was
23.87g (80% yield). The melting point of NTP was found to be between 178°C and 181°C.
The product was found to be soluble in DMSO and insoluble in ethanol.
4.4 Discussion
20
4.4.1 Michael Addition
Nitriliotripropionic acid was formed through the Michael addition between β-
alanine, the nucleophile, and acrylic acid, the electrophile. The lone pair of electrons on
the nitrogen of β-alanine reacts with acrylic acid to reduce it to propionic acid which lacks
a double bond. This step is what the addition between ammonium hydroxide and acrylic
acid call the second step. With β-alanine, this step adds the second leg for NTP. This occurs
a second time to add the third leg. Once all three legs, have been added, the last proton
bonded to nitrogen is removed.
4.4.2 Solubility
The solubility of NTP was congruent with previous solubility studies.2
21
Figure 10. First step of Michael addition synthesis for NTP
22
Figure 11. Second step of Michael addition synthesis for NTP
23
4.4.3 Titration
For the titration of NTP with NaOH, HCl was added to fully protonate NTP. After
the aqueous solution of NTP was heated to promote crystal solubility, it was left to sit
overnight and some crystals crashed out of the solution and recrystallized.
Figure 12. Recrystallization of NTP
From the titration of NTP, pKa3 and pKa4 were found. pKa* and pKa# were
calculated through the assumption that all the protons are equivalent. The titration curve is
similar to previous literature1, however, the pKa’s associated with NTP are all considerably
different form previous literature (Table 1).
24
Figure 13. Titration of NTP in NaOH
25
Figure 14. Potentiometric analysis of NTP in an aqueous medium1
Table 1. Experimental NTP protonation constants comparison to Govender and Wicker
pKa3 pKa* pKa# pKa4
Govender3 2.71 3.77 4.28 9.59
Wicker1 2.80094 3.69097 4.57621 9.44725
Experimental 2.5139 3.5608 5.4755 8.9512
When the pH of NTP is below two, it is assumed to be fully protonated. As the pH
increases, protons begin to disassociate from the parent molecule until all protons have
been removed. Full deprotonation occurs above an approximate basic pH of nine, in which
NTP is at its maximum potential for coordination. This makes coordination possible at all
of the carboxyl groups and the lone pair electrons of nitrogen.
26
Figure 15. Predicted species of NTP in an aqueous medium1
Figure 16. NTP speciation concentration diagram1
27
4.4.4 Symmetry.
Group theory, the mathematical treatment of the properties of point groups, was
used to determine the point group of NTP. NTP has neither a low nor high symmetry.
NTP’s highest order of rotation axis is C# through the nitrogen atom’s z axis. The next step
in determining the symmetry of NTP by group theory is whether to classify it in a D, C, or
S group. Researchers have claimed that the point group of NTP is equal to D#6.1 However,
for a D#6 point group, the molecule must have at least one C* axis perpendicular to the
principle C7 axis. A molecule such as NTP with a lone pair of electrons on the central atom
has a mutual electron repulsion that causes each leg of NTP to bend downward in the same
fashion as ammonia (Figure 8). Therefore, NTP cannot be D#6, or any other D group. NTP
does not have horizontal mirror reflections, but does have vertical mirror reflections, which
classifies it as a C#8 molecule.
Figure 17. 3-D ammonia molecule4
NTP has the same symmetry elements as ammonia. It has identity element E, two
rotation or operations (C#andC#* both through nitrogen), and three mirror reflections for
28
a total of six symmetry elements. Each mirror reflection goes through a leg of NTP,
vertically.
4.4.5 Melting Point
Previous research states that the melting point of 84.68% pure NTP is 179.82°C.1
The melting point found is well within range of these findings.
4.5 Conclusion
From the solubility test and melting point test, it can be concluded that NTP was
successfully made. The process of forming NTP from β-alanine and acrylic acid was faster
than previous methods and produced a substantial yield. The conclusion that the time-
consuming process is due to the third step of reaction has been disproven. Due to the first
leg of NTP already being attached, it can be concluded that the formation of the primary
amine compound, the first step, is the rate limiting step.
It has also been concluded that NTP fully deprotonates in basic mediums, making
it the optimal environment for coordination to metal ion. This confirms the pH dependency
of NTP coordination.5 Future studies of NTP coordination should be conducted in basic
mediums or with a salt form of NTP to allow maximum potential for coordination.
29
4.6 Literature Cited
1. Wicker, S. A. Development of a Green Soft Chemical Method for the Synthesis of Cathode Materials Utilized in Lithium-ion Energy Storage Technologies. Dissertation, Southern University and A & M College, Baton Rouge, Louisiana, 2011. 2. Sims, T. E. THE SYNTHESIS, STRUCTURAL, AND PHYSICOCHEMICAL CHARACTERIZATION OF 3,3’,3’’ NITRILOTRIPROPIONIC ACID. Southern University and A&M College, Baton Rouge, Louisiana, 2015. 3. Govender, K. K. Theoretical studies of nitrilotriacetic acid and nitrilotripropionic acid geometries for estimation of the stability of metal complexes by Density Functional Theory. Dissertation, University of Pretoria, Pretoria, 2009. 4. Bruce Averill, P. E., Chemistry: Principles, Patterns, and Applications 1st ed.; Pearson: San Francisco, 2007; p 1250. 5. Carroll, C. Determining the Stoichiometric Ratio of Iron(III) Chloride and synthesized Nitrilotripropionic Acid using the Job’s Method. Southern University and A&M College, Baton Rouge, Louisiana, 2015.
30
CHAPTER IV: STOICHIOMETRIC RATIO OF NITRILOTRIPROPIONIC
ACID TO CUPRIC CHLORIDE IN A NON-AQUEOUS MEDIUM USING
THE JOB’S METHOD
4.1 Introduction
The coordination of NTP is dependent upon its pH.1 In basic mediums, NTP fully
deprotonates making it more likely to coordinate with metal ions. DMSO contains lone
pair electrons that causes it to exhibit basic properties. The polar properties of DMSO make
NTP soluble in the solvent. DMSO can coordinate to metal ions through either the oxygen
or sulfur atom (Figure 1). Spectrophotometry is used to discover the composition of
complex ions and solutions. In the method of continuous variations or the Job’s method,
cation and ligand solutions with identical concentrations are mixed so that the total volume
of the solution and the total number of moles of each reactant in each mixture are constant
but the mole ratio varies systematically.2
In this chapter, the stoichiometric ratio of the NTP ligand to the Copper (II) ion will
be evaluated through use of the Job’s method. If the NTP ligand successfully coordinates
to Copper, then a distinct color change will occur.
4.2 Experimental Method
4.2.1 Materials
31
Fisher Science Education Cupric chloride, anhydrous, laboratory grade. Sigma-
Aldrich Chemistry dimethyl sulfoxide, for UV-spectroscopy, 99.8%. Volumetric flask (3),
100mL. Synthesized NTP. Volumetric flask, 250mL. Glass vial, (11), 10mL. Vernier
SpectroVis Plus.
4.2.2 Procedure
A 2.053 ∗ 10@#M solution of NTP was made by dissolving 5.8254g of NTP into a
250mL volumetric flask of DMSO. The solution should be lightly heated and stirred to aid
dissolving. Then, 2.05mL of the solution was placed in a 100mL volumetric flask and filled
with DMSO. A 2.053 ∗ 10@#M solution of CuCl* was made by dissolving 1.3697g
ofCuCl* into a 100mL volumetric flask of DMSO. Then, 2mL of the solution was placed
in a 100mL volumetric flask and filled with DMSO. Solutions totaling 5 mL each were
made in accordance with Table 2 and placed in 10 mL glass vials. The UV spectrum of
each solution was found using the Vernier SpectroVis Plus.
Table 2. Phase Diagram for NTP with Copper (II) Chloride in DMSO
VolumeNTP(L)
molesofNTP
VolumeCopper(II)Chloride(L)
molesofCopper(II)ion
TotalMolesMoleFraction
ofLigand
MoleFractionof
Metal
MoleRatioofLigandtoMetal
0 0.0000E+00 0.005 1.0265E-05 1.0265E-05 0 1 0/10.0005 1.0265E-06 0.0045 9.2385E-06 1.0265E-05 0.1 0.9 1/90.001 2.0530E-06 0.004 8.2120E-06 1.0265E-05 0.2 0.8 1/40.0015 3.0795E-06 0.0035 7.1855E-06 1.0265E-05 0.3 0.7 3/70.002 4.1060E-06 0.003 6.1590E-06 1.0265E-05 0.4 0.6 2/30.0025 5.1325E-06 0.0025 5.1325E-06 1.0265E-05 0.5 0.5 1/10.003 6.1590E-06 0.002 4.1060E-06 1.0265E-05 0.6 0.4 3/20.0035 7.1855E-06 0.0015 3.0795E-06 1.0265E-05 0.7 0.3 7/30.004 8.2120E-06 0.001 2.0530E-06 1.0265E-05 0.8 0.2 4/10.0045 9.2385E-06 0.0005 1.0265E-06 1.0265E-05 0.9 0.1 9/10.005 1.0265E-05 0 0.0000E+00 1.0265E-05 1 0 1/0
MolarityofNTP(M)
MolarityofCopper(II)Chloride(M)
TotalVolume(mL)
0.002053 0.002053 5
32
4.3 Results
The spectrums of each graph were combined and peaks were found at 391.6 nm
and 759.5 nm. A possible peak is slightly visible beyond 899 nm but was not captured with
available instrumentation. The spectrum of NTP, below 380 nm, was also not captured due
to the limits of the instrumentation. There was a variation of color in the different solutions.
Figure 18. Varying ratios (M:L) of 2mM Copper (II) chloride and 2mM NTP in DMSO. From left to right: 1:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9, 0:1.
Figure 19. Varying ratios (M:L) of 0.05M Copper (II) chloride and 0.05M NTP in DMSO. From left to right: 1:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9, 0:1.
33
Figure 20. Spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO
4.4 Discussion
DMSO is a highly nucleophilic solvent with a large electron density around both
the sulfur and oxygen atoms. DMSO can use its lone pairs to donate to protons on other
molecules, making it a common ligand in coordination chemistry. It resonates between two
different species (Figure 10), both of which are excellent for coordination or acid-base
chemistry. Bonding typically occurs on the oxygen atom where it is the most
electronegative, but can also occur on the sulfur atom. DMSO is highly polar and is known
to form compounds with Lewis acids.3 Strong acids such as hydrochloric acid and sulfuric
acid dissociate completely in DMSO3 making it a basic compound.
0
0.1
0.2
0.3
0.4
0.5
0.6
380 480 580 680 780 880
Absorban
ce
Wavelength(nm)
ContinuousVariationof0.002MCuCl_2and0.002MNTPinDMSO
1:0
9:1
8:2
7:3
6:4
5:5
4:6
3:7
2:8
1:9
0:1
Metal toLigandRatio
Peak=391.6nm
34
Figure 21. Resonance structures of DMSO
When compared to water, the spectrochemical series shows that DMSO is a weaker
field ligand which gives it a higher spend than water.4 This can be seen visually when an
aqueous solution of Copper (II) chloride and a non-aqueous solution of Copper (II) chloride
in DMSO are compared (Figure 23). The blue color is attributed to water being in the
coordination sphere while the green represents DMSO in the coordination sphere. For the
color of a solution of DMSO and Copper (II) chloride to go from green to blue after the
addition of a NTP and DMSO solution shows that the DMSO was in fact displaced by the
NTP ligand. Graphically, this is demonstrated by the new peak that emerges in Figure 24
at 759.5 nm at a metal to ligand ratio of 3:7. This gives some insight to the stoichiometric
ratio, but other methods must be conducted to find an exact ratio.
Figure 22. Copper (II) chloride in water and Copper (II) chloride in DMSO
35
Figure 23. Spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO from 680 nm-800 nm
The possible peak slightly visible beyond 899 nm (Figure 25) gives rise to another
species, leading to a total of two definite species in the solution and one possible.
Figure 24. Spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO from 680 nm-900 nm
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
680 700 720 740 760 780 800
Absorban
ce
Wavelength(nm)
ContinuousVariationof0.002MCuCl_2andNTPbetween680nmand800nm
1:0
9:1
8:2
7:3
6:4
5:5
4:6
3:7
2:8
1:9
0:1
Metal toLigandRatio
0
0.05
0.1
0.15
0.2
0.25
680 730 780 830 880
Absorban
ce
Wavelength(nm)
ContinuousVariationof0.002MCuCl_2ansNTPbetween680nmand900nm
1:0
9:1
8:2
7:3
6:4
5:5
4:6
3:7
2:8
1:9
0:1
Metal toLigandRatio
Peak=760.3nm
Peak=760.3nm
36
The continuous variation of NTP and Copper (II) chloride in DMSO led to a natural
calibration curve forming for the disappearance of the peak associated with Copper (II)
chloride in DMSO. Using the slope of the line-of-best-fit, the molar extinction coefficient
of Copper (II) chloride in DMSO was calculated at a wavelength of 391.6 nm and found to
be 299.38 L mol-1 cm-1. This is only an approximate value.
Figure 25. Spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO from 380 nm-480 nm
Figure 26. Calibration curve of Copper (II) Chloride in DMSO
y=299.38x- 0.1014
0
0.1
0.2
0.3
0.4
0.5
0.6
0 0.0005 0.001 0.0015 0.002
Absorban
ce
Concentration(M)
Absorbanceat391.6nm
0
0.1
0.2
0.3
0.4
0.5
0.6
380 390 400 410 420 430 440 450 460 470 480
Absorban
ce
Wavelength(nm)
ContinuousVariationof0.002MCuCl_2andNTPbetween380nmand480nm
1:09:18:27:36:45:54:63:72:81:90:1
Metal toLigandRatio
Peak=391.6nm
37
At metal to ligand ratios of 1:9, 2:8, 3:7, and 4:6, various species are present in
solution. The exact identity of these species could be determined in the future using
Infrared (IR) spectroscopy.
Figure 27. Enhanced spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO at (from top left to right to bottom left to right) metal to ligand ratios of 4:6, 3:7, 2:8, and 1:9
Upon closer look at the 1:9 metal to ligand ratio, one single peak can be identified to signal
the emergence of a Copper-NTP complex. A 0.05M Copper solution in DMSO and a
0.05M NTP solution in DMSO were used to obtain a clearly defined and verifiable species.
38
Figure 28. Spectrum of 1:9 Metal to Ligand Ratio of 0.05M NTP and 0.05M Copper (II) Chloride in DMSO
At 391 nm, the octahedral crystal field splitting energy, ∆D, of the copper-DMSO
complex is 306 kJ/mol. At 726.7 nm, the ∆D of the emerging copper-NTP complex is 165
kJ/mol. The larger energy of the copper-DMSO complex signifies that DMSO is higher in
the spectrochemical series than NTP. The similarity of visible color between the copper-
NTP complex and the copper (II) ion solution in water allows for speculation that NTP and
water are close in the spectrochemical series and that DMSO is higher than water
(H*O~NTP < DMSO).
Figure 29. Spectrochemical series
4.5 Conclusion
In conclusion, the NTP ligand successfully coordinated to Copper, as observed by
the distinct color changes with varying metal to ligand ratios. A single new peak emerged
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
380 480 580 680 780 880
Absorban
ce
Wavelength(nm)
Absorbanceof1:90.05MCuCl_2and0.05MNTPinDMSO
Peak=726.7nm
!" < $%" < &'" < (&)" < )*+" < ," < *-" < -.* < )&(" < &/-/) < )-+ < 01 < )*." < 22ℎ+ < &)" < &* High spin Low spin Weak field Strong field Small ∆ Large ∆
39
at 726.7 nm at a metal to ligand ratio of 1:9, giving a starting point for future studies for
finding the to the stoichiometric ratio. Other methods such as the mole-ratio and slope-ratio
methods should be examined to find an exact ratio.
40
4.6 Literature Cited
1. Carroll, C. Determining the Stoichiometric Ratio of Iron(III) Chloride and synthesized Nitrilotripropionic Acid using the Job’s Method. Southern University and A&M College, Baton Rouge, Louisiana, 2015. 2. Douglas A. Skoog, F. J. H., Stanley R. Crouch, Principles of Instrumental Analysis. 6 ed.; Thomson Brooks/Cole: Belmont, 2006; p 1056. 3. I. M. KOLTHOFF, T. B. R., Acid-Base Strength in Dimethyl Sulfoxide. Inorganic Chemistry 1962, 1 (2), 189-194. 4. Devon W. Meek, R. S. D., T. S. Piper, Spectrochemical Studies of Dimethyl Sulfoxide, Tetramethylene Sulfoxide, and Pyridine N-Oxide as Ligands with Nickel(II), Chromium(III), and Cobalt(II). Inorganic Chemistry 1962, 1 (2), 285-289.
41
BIOGRAPHY
I am Nsombi Jahiare Roberts from Palm Bay, Florida. I come from a family of eight
half siblings, where I am the oldest, and four step-siblings, where I am the second youngest.
I am currently a 22-year-old Chemistry major and Mathematics minor at Southern
University and A&M College in Baton Rouge, Louisiana as well as a Midshipman in the
Southern University Naval Reserve Officer Training Corps (NROTC). I am a Spring 2014
initiate of the Beta Alpha chapter of Zeta Phi Beta Sorority, Incorporated.
Upon graduation, I will commission into the United States Navy as the first
African-American woman from NROTC to serve aboard a nuclear submarine as an officer.
My degree in Chemistry will provide me with the training needed to lead sailors working
with the Navy’s numerous nuclear reactors. My inspiration for choosing such a route came
from my constant need for intellectual challenges and my prior affiliation with the military
in high school. Once I have completed my degree and commissioned, I hope to be a positive
guide for my younger siblings to follow and someone that they can use as an example of
how hard work and determination pays off.
42
Nsombi J. Roberts [email protected]
CURRENT ADDRESS Southern University P.O. Box 9842 Baton Rouge, LA 70813 (321) 208-3535
PERMANENT ADDRESS 625 Loffler Cir. SE
APT 104 Palm Bay, FL 32909
(321) 327-4978
EDUCATION___________________________________________________________ Southern University and A&M College Baton Rouge, Louisiana Major: Chemistry Minor: Mathematics Graduation Date: 13 May 2016 Cumulative GPA: 3.85 Bayside High School Palm Bay, FL Accelerated College Credit High School Diploma Graduation Date: May 2012 Cumulative GPA: 3.76 WORK EXPERIENCE___________________________________________________ Southern University and A&M College Baton Rouge, LA Supplemental Instruction Leader August 2015 to October 2015
• Lead Supplemental Instruction lessons in General Chemistry Southern University and A&M College Baton Rouge, LA Tutor February 2015 to May 2015
• Tutor in Mathematics and Science 7-Eleven Palm Bay, FL Certified Sales Associate July 2010 to August 2013
• Organized food menus and ordered food products for sale • Managed and recorded food sales • Assisted in training incoming employees • Held responsible for opening and ending daily shifts • Ordered key merchandise for retail sale
43
HONORS_______________________________________________________________ • Selected for Naval Submarine Officer designation • Mu Zeta Foundation Scholarship, Spring 2015 • Zeta Phi Beta Sorority, Inc. Life Members Scholarship, Spring 2015 • Dean’s List- Fall 2012- Present • Highest Average in Military Science Navy ROTC, Spring 2014, Spring 2015 • Highest Average in the Honors College & Military Science Navy ROTC, Spring
2013 • Dolores Spikes Honors College Scholarship, 2012 • Minority Serving Institution Scholarship Reservation, 2012
ACTIVITIES____________________________________________________________
• Black College Quiz game show, 2015 Competitor; 2nd place in round • Zeta Phi Beta Sorority Incorporated 2014-present, 2014-2015 Secretary • Beta Kappa Chi Scientific Honor Society, 2014-2015 Student National Secretary • National Institute of Science, 2014-2015 Student National Secretary • Southern University Naval Reserve Officer Training Corps, Actions Officer- Spring 2016 • Southern University Naval Reserve Officer Training Corps. Command Management and
Equal Opportunity Team Leader • Southern University Naval Reserve Officer Training Corps, Assistant Actions Officer-
Spring 2015 • Southern University Naval Reserve Officer Training Corps, Assistant Administrative
Officer-Fall 2014 • Southern University Naval Reserve Officer Training Corps, Academics Officer- Fall
2014 • Southern University Honda Campus All-Star Challenge, Team Member, Fall 2013-
Spring 2015 • Student Government Association, Member • Louisiana Collegiate Honors Council, Member • Association of Women Students, Member
SKILLS________________________________________________________________
• Proficient in Microsoft Office, Open Office, and Windows Movie Maker References available upon request
44
APPROVAL FOR SCHOLARLY DISSEMINATION
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Southern University and A&M College the right to reproduce, by appropriate methods,
upon request, any or all portions of this thesis.
It is understood that “request” consists of agreement, on the part of the requesting
party, that said reproduction is for his or her personal use and that subsequent reproduction
will not occur without the written approval of the author of the thesis.
The author of this thesis reserves the right to publish freely, in the literature, at any
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Author___________________________________
Date_____________________________________