journal of mineral, metal and material engineering, 2019 ... · surface coating of abu tartur...

Journal of Mineral, Metal and Material Engineering, 2019, 5, 22-32 22

E-ISSN: 2414-2115/19 © 2019 Scientific Array

Preparation and Surface Coating of Abu Tartur Egyptian Glauconite as Filter Media for Removing Soluble Iron and Manganese from Water

M.K. Abd El-Rahman1,* and J. Werther 2

1Central Metallurgical Research and Development Institute, P.O. Box: 87 Helwan, Cairo, Egypt 2Technical University of Hamburg, Dep. of Chemical Eng., Deniake Street. 15, 21073 Hamburg, Germany

Abstract: This work aims to prepare suitable particle size of Egyptian Abu Tartur glauconite meeting the standard specification for water treatment and surface coating of it with manganese oxide for removing soluble iron and manganese from water. Size fraction between 850 and 250 micron were prepared using mineral processing technology and used for coating with manganese dioxide. Two different techniques for coating of glauconite granule were conducted. The first one put the granule in filtration column and putting the chemical for coating. The second one is using a stirring tank for coating. Iron and manganese solution with different concentrate were prepared. The un-coated and coated glauconite was conducted for removal soluble manganese and iron. It was put in a filtration column for removing soluble iron and manganese from prepared solutions.

Results showed that in case of un-coated glauconite at concentration of 20 ppm manganese and iron the removal percentage was 99.9 % for manganese and 81 % for iron. After this concentration the removal percentage of both manganese and iron was decreased and reached to 3.41% at concentration 97 ppm manganese and 1.11% at concentration 90 ppm iron.

In case of coated glauconite was noticed that at concentration of manganese varied from 10 ppm to 80 ppm the average of manganese removal percentage reached to 96.9 %. In case of iron at concentration varied from 10 ppm to 212 ppm the average removal percentage of iron was 99.9 %.

Keywords: Greensand, Coating of glauconite, Filter media, Removal of iron and manganese from water, Heavy metal removal from water.

1. INTRODUCTION

Greensand is name given to sediments rich in the bluish green to greenish black mineral known as glauconite [1]. It is a naturally occurring mineral that is granular in appearance. It is a hydrous iron potassium silicate. It has been used for different applications such as agriculture, heavy metal removal from water and wastewater treatment.

Manganese greensand is formulated from a glauconite coated with manganese oxides. The manganese dioxide acts as a catalyst in the oxidation-reduction reaction of iron and manganese. Therefore it is used for the removal of soluble iron, manganese and hydrogen sulfide from water.

The manganese greensand is prepared by three steps [2]. The first step is ion exchange. In this step the glauconite is exposed to manganese sulfide or sulfate. The manganese sulfide dissociates and the manganese (Mn2+) replaces sodium or potassium in the glauconite. The second step is the activation. Potassium permanganate is added in this step to *Address correspondence to this author at the Central Metallurgical R & D Institute, P.O.Box 87 Helwan, Cairo, Egypt; Tel: (0202) 25010642; Ext: 185; Fax: + 202-25010639; Email: [email protected]

oxidize the media to a high oxidation state that will readily remove reduced ions by oxidation. The potassium permanganate also contributes more manganese to the surface. After these two steps are repeated several times, the greensand is ready to be shipped for use in water treatment systems.

The third step is the deactivation. This step represents the actual use of the media to remove common ions that are undesirable in drinking water, through a simple oxidation reduction reaction. The manganese oxide coating of the glauconite oxidizes the ions to a higher charge. The manganese oxide coating is reduced to a lower charge as it accumulates oxygen or electrons. The manganese greensand’s surface is re-oxidized through the use of potassium permanganate.

Tobiason 2016 [3] reviewed the manganese occurrence and summarizes recent research on removal mechanisms practiced in drinking water treatment. Manganese is removed by physical, chemical, and biological processes or by a combination of these methods.

Mineral processing and beneficiation technologies (crushing and grinding, sizing, washing and scrubbing, gravity concentration, and magnetic separation) are finding application in processing of glauconitic sand [4].

Surface Coating of Abu Tartur Egyptian Glauconite as Filter Media Journal of Mineral, Metal and Material Engineering, 2019, Vol. 5 23

Greensand products for water softening generally consisted of several different grades, depending on the particular treatment of the glauconite was given during processing [5]. The standard greensand water softener was produced from natural glauconite after being washed and classified. Processed green sand is used in water treatment to remove soluble iron and manganese salts. The grain size of processed glauconite is range from 0.84 to 0.25 mm. The grain size of processed glauconite is range from 0.84 to 0.25 mm and the effective size in water softening is 0.3 to 0.33 mm [1].

Bazilio et al., (2016) [6], studied full-Scale implementation of second-stage contactors for manganese removal. The use of post-filtration contactors for the removal of manganese (Mn2+) in the dissolved, reduced form (Mn2+) by sorption to manganese oxide–coated granular media and catalytic oxidation by free chlorine was implemented at the Lantern Hill Water Treatment Plant.

In Egypt there are huge resources of glauconite clays associated with iron and phosphate ores deposits in Bahariya Oasis, in Abu Tartur, El-Dakhla, and El- Kharga Oasis (West Desert), and Qusseir-Safaga (Red Sea Coast).

Crushing, grinding, attrition scrubbing, soaking and stirring were studied on Bahariya Oasis Egypt in order to prepare suitable size for agriculture, water treatment and oil bleaching [7].

Selim et al., (2018) studied the removal of heavy metal using coating Abu Tartur Egyptian glauconite [8].

Preparation suitable particle size of Abu Tartur glauconite meeting the standard specification for water treatment and surface coating of it with manganese oxide is the main objective of this work for removing soluble iron and manganese from water.

2. EXPERIMENTAL TECHNIQUE

2.1. Materials

Sodium aluminates, Sodium Silicate, Aluminum sulfate, Manganese sulfate and Potassium permanganate all chemicals very pure from (Sigma Aldrich) Merck

Two representative samples of glauconite were used. The first sample is collected from Abu Tartur phosphate mine and the second one is collected from

outcrop of the glauconite bed. The samples were crushed using Denver jaw crusher to pass 100 % less than 25 mm. Small representative samples were taken for size analysis and chemical analysis.

2.2. Methods

2.2.1. Preparation Glauconite for Water Treatment

Different techniques are used for preparation the suitable size fraction of glauconite according to the specification of glauconite for water treatment followed by surface coating with manganese dioxide. The techniques involve soaking in water, stirring, and attrition scrubber at different time. After treatment samples were screened on sieve size 75 micron and samples were taken for size analysis. The treated samples were sieved to separate suitable sandy from size less than 850 to 250 micron size fraction. A development balance flowsheet was suggested.

2.2.2. Coating of Glauconite Granule

Two coating technique were conducted. The first one put the granule in filtration column and putting the chemical for coating. The second one is using a stirring tank for coating. 500 gram of glauconite size (between 850 and 250 micron) was put in filtration column and stirrer tank. The sample was washed by water to remove the slime less than 75 micron. In case filtration column the sample was washed with water at rate 75 ml /min until no slime Figure 1. In case stirring the sample was stirred at low speed and remove the fines by sieving on sieve 75 micron. For hardness of glauconite granules 2 % sodium aluminate, 2 % sodium silicate (twice), 2 % aluminum sulfate was added for both techniques. 0.002 molar manganese sulfate and 0.0005 molar potassium permanganate solutions were prepared for coating process. First step manganese sulfate solution about one liter was added. In case of stirring was stirred for half an hour at low speed and removing the solution. In case filtration column one liter of manganese sulfate was added at rate of 40 ml/minute. Manganese sample solution before and after treatment was taken for analysis using atomic absorbance. The second step potassium permanganate was added in filtration column at rate of 50 mil/min and in stirrer tank and stirring for half an hour. The color of potassium permanganate was disappeared during addition. The addition of potassium permanganate continues added until faint pink appears. The step one and two was repeated ten times. The coated glauconite was discharged, dried and used as filter media for removing soluble manganese and iron. The coated glauconite was used

24 Journal of Mineral, Metal and Material Engineering, 2019, Vol. 5 El-Rahman and Werther

for soluble iron and manganese removal. Iron and manganese solution with different concentrate were prepared. A 300 gram of coated glauconite was put in a filtration column for removing soluble iron and manganese from prepared solutions. Water before and after filtration was analyzed. A back wash of filtration column was carried out. Figure 2 illustrates expermintal setup for removal of soulble iron, manganese and backwash.

3. RESULTS AND DISCUSSIONS

3.1. Crushing of Glauconite

Table 1 represents complete chemical analysis Abu Tartur glauconite clay. Figure 3 illustrates the results of crushing of Abu Tartur mine and the outcrop bed using jaw crusher. It has been seen that about 94 % by weight of Abu Tartur passing from sieve size 22 mm, 80 % by weight passing from sieve size 16 mm and 50 % by weight passing from sieve size 9 mm. About 80 % by weight of out crop is passing from sieve size 2 mm and 50 % by weight is passing from sieve size 0.5 mm.

3.2. Results of Preparation Glauconite for Water Treatment

Soaking, stirring and attrition scrubber techniques were carried out to prepare suitable size fraction of glauconite according to the specification of glauconite as filter media in water treatment.

Figure 4 illustrates the results of soaking of Abu Tartur mine glauconite for different time. It has been shown that the d80 and d50 for soaking one hour and

three hour are nearly the same and their values are 1800 and 300 micron. Table 2 shows the results of preparation of Abu Tartur mine glauconite for water treatment using soaking of it for different time. It has been shown that the weight percentage of size fraction between 850 and 250 micron is nearly the same in case soaking glauconite for one hour and three hour. The weight percentage of the size fraction between 850 and 250 micron represents 37 % by weight. It is concluded that the soaking for one hour technique are suitable for preparation of Abu Tartur mine for water treatment.

Figure 5 and 6 illustrated the size analysis of stirring and attrition scrubber of Abu Tartur mine glauconite. It has been shown that the d80 and d50 for stirring 15 min and one hour are nearly the same and their values are ranges 5000 and 300 micron. The d80 and d50 for attrition scrubber for 15 min and 30 min are nearly the same and their values are ranges 7000 and 200 micron.

Table 3 represents the results of stirring for 15 min, one hour and attrition scrubber of Abu Tartur glauconite for 15 min and 30 min. It is shown that with increasing the time of stirring and attrition scrubber the weight percentage of size fraction larger than 75 micron decreases and the weight percentage of fine fraction increases. The stirring for 15 min is better than both stirring for one hour and attrition scrubber due to it produces less fine fraction. The weight percentage of the size fraction larger than 75 micron at 15 min stirring represents about 85 % by weight compared with 73 % and 70 % by weight for one hour stirring and 15 min

Figure 1: Coating of glauconite with Manganese dioxide (A) Manganese sulfate, (B) Potassium permanganate (C) faint pink in filtrate.


attrition scrubber respectively. The results of preparing the suitable size for water treatments according the specification using stirring and attrition scrubber techniques showed that the stirring at 15 min gives good results than stirring for one hour and attrition scrubber. The size fraction between 850 and 250 micron represents about 37 % by weight in case of stirring for 15 min.

Figure 7 shows the results of laboratory size analysis of stirring and attrition scrubber of Abu Tartur outcrop glauconite. It has been shown that the d80 and d50 for stirring 10 min are 800 and 100 micron. Table 4 shows the results of preparing suitable size fraction for water treatment from Abu Tartur outcrop glauconite using stirring and attrition scrubber technique for 10 min. It is shown that the weight percentage of size larger than 75 micron represents 90 % by weight in case of stirring compared with 53 % in case attrition

scrubber for 10 min. This means that the attrition scrubber has stronger effects on Abu Tartur outcrop glauconite. It is shown that the weight percentage of size fraction between 850 and 250 micron in case of stirring for 10 min is 46 % by weight compared with 29 % by weight in case of attrition scrubber for 10 min. It is concluded that the stirring technique is suitable for preparation the Abu Tartur outcrop glauconite for water treatment. The suggested flowsheet for preparation suitable size between 850 and 250 micron for water treatment application from Abu Tartur mine was shown in Figure 8. It involves crushing using jaw crusher and screening on sieve size 25 mm. The size fraction less than 25 mm is stirred for 15 min at 1000 rpm, 50 % pulp density and followed by wet sieving using different sieve sizes. The fraction size between 850 and 250 micron represents about 37 % by weight which used for coating with manganese dioxide and used as filter

Figure 2: Experimental setup for Removal of Soluble Iron, Manganese and back wash.


media for removing of soluble iron and manganese from water.

Figure 3: Size analysis for crushing of Abu Tartur glacounite.

Figure 4: Size analysis for soaking Abu Tartur mine glauconite for water treatment.

Table 2: Preparation of Suitable Size for Coating from Abu Tartur Mine Glauconite by Soaking

Weight %

Size, Micron Soaking for One Hour

Soaking for Three Hour

- 9000 + 850 22.87 27.17

-850 + 250 37.41 34.27

-250 + 75 27.90 26.62

-75 11.82 11.93

Total 100.00 100.00

Figure 5: Size analysis for Stirring Abu Tartur mine glauconite for water treatment.

Table 1: Complete Chemical Analysis of Abu Tartur Glauconite Clay

Eastern Section First Mine Sample Mine Sample

Constituent Percentage

SiO2 44.65 56.52 41.30

Al2O3 5.15 7.80 5.75

Fe2O3 18.70 15.46 12.37

MgO 2.06 1.90 2.45

K2O 4.88 7.25 4.00

MnO 0.25 0.13 1.03

TiO2 0.14 0.10 0.11

CaO 7.02 2.20 11.32

P2O5 6.00 1.56 2.48

SO3 1.64 0.38 2.78

L.O.I 9.18 5.84 16.23


Figure 6: Size analysis for Attrition scrubber of Abu Tartur mine glauconite.

Figure 7: Size analysis of stirred and attrition scrubber of Abu Tartur outcrop glauconite.

3.3. Coating of Glauconite

Coating of glauconite with manganese dioxide was carried out using two techniques stirring and filtration

column. Table 5 shows the results of coated of glauconite using stirring technique. It has been shown that the average of adsorption of manganese dioxide was 97 %.

Table 4: Preparation of Suitable Size for Coating from Abu Tartur Outcrop Glauconite by Stirring and Attrition Scrubber

Weight %

Size, micron Stirring 1000 rpm 10 min.

Attrition scrubber, 10 min.

+ 850 22.65 15.00

-850 + 250 46.22 29.10

-250 21.13 8.40

-75 10.00 47.50

Total 100.00 100.00

Table 6 illustrates the results of coating of

glauconite using filtration column. It has been seen that the average of adsorbed manganese dioxide was 99.94 %. Results showed that both techniques are suitable for coating of glauconite with manganese dioxide. Figure 9 represents glauconite before and after coating. The filtration unit was filled with 300 gram coated glauconite to be used as filter media to remove soluble iron and manganese.

3.4. Removal of Soluble Manganese and Iron

3.4.1. Removal of Soluble Manganese and Iron with Un-Coated Glauconite

Table 7 illustrates the results of removal of soluble manganese and iron from solution containing manganese and iron using un-coated glauconite. It has been seen that at concentration of 20 ppm manganese and iron the removal percentage was 99.9 % for

Table 3: Preparation of Suitable Size for Coating from Abu Tartur Mine Glauconite by Stirring and Attrition Scrubber

Stirring 1000 rpm Attrition scrubber

Weight %

Size, micron For 15 min For one hour For 15 min For 30 min

- 9000 + 850 28.99 24.78 29.45 24.58

-850 + 250 36.80 26.25 16.39 17.84

-250 18.83 21.63 24.40 24.99

-75 15.38 27.34 29.76 32.59

Total 100.00 100.00 100.00 100.00


manganese and 81 % for iron. After this concentration the removal percentage of both manganese and iron was decreased. The removal percentage reached to 3.41% at concentration 97 ppm manganese and 1.11%

at concentration 90 ppm iron. Therefore in order to improve the efficiency of removal percentage the coated glauconite could be used.

Figure 8: Flowsheet for wet process of Abu Tartur mine Glauconite for Water treatment.

Table 5: Coating of Glauconite by Manganese Dioxide using Stirring Technique

Manganese Concentrate, ppm % Adsorbed

Added (CI) After (Cf) Adsorded = (CI - Cf) (CI - Cf) / CI) *100

106 0.6 105.4 99.43

106 0.58 105.42 99.45

106 1.04 104.96 99.02

106 2.54 103.46 97.60

106 9.24 96.76 91.28

Average

106 2.8 103.2 97.36


3.4.2. Removal of Soluble Manganese and Iron with Coated Glauconite

Table 8 summarizes the results of removal soluble manganese from solution containing manganese only and removal of soluble iron from solution containing iron only. It has been seen that in case manganese at concentration varied from 10 ppm to 195 ppm the average removal percentage of manganese was 99.8 % meanwhile at concentration about 206 ppm the removal percentage of manganese was 95 %. In case

of iron that at varied from 7.5 ppm to 212 ppm the average removal percentage of iron was 99.91 %. Table 9 represents the results of removal of soluble manganese and iron from solution containing manganese and iron together. It has been seen that at concentration of manganese varied from 10 ppm to 80 ppm the average of manganese removal percentage reached to 96.9 %. At manganese concentrate varied from 100 ppm to 176 ppm the average removal percentage was 75.2 %. In case of iron at concentration varied from 10 ppm to 212 ppm the

Table 6: Coating of Glauconite by Manganese Dioxide using Filtration Coulmn

Manganese Concentrate, ppm % Adsorbed

Added (CI) After (Cf) Adeorbed = (CI - Cf) (CI - Cf) / CI) *100

106 0.02 105.98 99.98

106 0.04 105.96 99.96

106 0.02 105.98 99.98

106 0.03 105.97 99.97

106 0.02 105.98 99.98

106 0.02 105.98 99.98

106 0.16 105.84 99.85

106 0.09 105.91 99.92

106 0.14 105.86 99.87

106 0.09 105.91 99.92

Average

106 0.063 105.94 99.94

Figure 9: Coating of glauconite with Manganese dioxide for use as filter media.


average removal percentage of iron was 99.9 %. Figure 10 represents the water before and after filtration.

CONCLUSION

Egyptian glaucounite in size between 850 micron and 250 micron was prepared using stirring followed by screening technique. It is coated with manganese dioxide to be used as filter media to be suitable for removing soluble iron and manganese using two techniques. One was stirring the glauconite in stirrer tank and the other using the filtration unit. Both techniques were suitable for coating glauconite with

manganese dioxide. The un-coated and coated glauconite was conducted for removal soluble manganese and iron. In case of un-coated glauconite at concentration of 20 ppm manganese and iron the removal percentage was 99.9 % for manganese and 81 % for iron. After this concentration the removal percentage of both manganese and iron was decreased and reached to 3.41% at concentration 97 ppm manganese and 1.11% at concentration 90 ppm iron. Coated glauconite was conducted for removal of soluble manganese and iron from solution containing manganese only, iron only and solution containing both soluble manganese and iron. In case manganese at concentration varied from 10 ppm to 195 ppm the

Table 7: Removal of Soluble Iron and Manganese in Solution Using un-coated Glauconite

Solution containing Manganese and Iron together

Manganese % Removal Iron % Removal

Concentrate (ppm) (Cb - Cf) / CI) *100 Concentrate (ppm) (Cb - Cf) / CI) *100

Before (Cb) Filtrate (Cf) Manganese Before (Cb) Filtrate (Cf) Iron

19.9 0.02 99.90 19.9 3.8 80.90

40.8 10.3 74.75 40.8 25.5 37.50

60.5 29.04 52.00 61 46.8 23.28

80.5 61.18 24.00 81.5 70.84 13.08

96.8 93.5 3.41 90 89 1.11

Table 8: Removal of Soluble Manganese and Iron Using Coated Glauconite

Solution containing Manganese only Solution containing Iron only

Manganese % removal Iron % removal



9.8 0.02 99.80 7.53 0.02 99.73

20.8 0.05 99.76 11.6 0.02 99.83

48.1 0.1 99.79 17.6 0.02 99.89

80.2 0.02 99.98 26.1 0.02 99.92

90.6 0.2 99.78 33.7 0.02 99.94

141 0.05 99.96 44.1 0.02 99.95

195 0.6 99.69 83.1 0.02 99.98

206 10.4 94.95 102 0.02 99.98

152 0.06 99.96

212 0.24 99.89


average removal percentage of manganese was 99.8 %. In case of iron at concentration varied from 7.5 ppm to 212 ppm the average removal percentage of iron was 99.91 %. In case of solution containing both manganese and iron together was seen that at concentration of manganese varied from 10 ppm to 80 ppm the average of manganese removal percentage reached to 96.9 % and at manganese concentrate varied from 100 ppm to 176 ppm the average removal percentage was 75.2 %. In case of iron at concentration varied from 10 ppm to 212 ppm the average removal percentage of iron was 99.9 %.

REFERENCES

[1] MK. Abd El-Rahman, Degritting of gluaconite clay by different techniques for use in water treatment and as fertilizer, (1) supplement, Mineral Processing and Extractive Metallurgy (Trans. Inst. Min. Metall. C) 2006; 115(3): 145-149 https://doi.org/10.1179/174328506X109095

[2] Ficek, Kenneth J. “Potassium Permanganate /Manganese Greensand for Removal of Metals,” Water Quality Association Convention, March 1994.

[3] Tobiason, Mai, Bazilio, Nguyen and Goodwill, Manganese Removal from Drinking Water Sources, Curr Pollution Rep 2016; 2: 168-177 https://doi.org/10.1007/s40726-016-0036-2

Table 9: Removal of Soluble Iron and Manganese Using Coated Glauconite

Solution Containing Manganese and Iron Together

Manganese % removal Iron % removal



10.3 0.03 99.71 10.2 0.02 99.80

20.5 0.42 97.95 20.2 0.02 99.90

25 0.96 97.95 24.5 0.01 99.98

42.2 0.87 97.94 41.4 0.06 99.86

55 1.16 97.89 54 0.06 99.89

60.5 1.92 96.83 59.5 0.06 99.90

82 8.19 90.01 82 0.08 99.90

100 17 83.00 100 0.12 99.88

164 42.9 73.84 158 0.06 99.96

176 55 68.75 167 0.16 99.90

218 144 33.94 212 0.24 99.89

Figure 10: Removal of Soluble Iron and Manganese.




[6] Bazilio, Kaminski, Larsen, Mai, and Tobiason, Full-Scale Implementation of Second-Stage Contactors for Manganese Removal, Journal American Water Works Association 2016;

108: 606-614 https://doi.org/10.5942/jawwa.2016.108.0184

[7] MK. Abd El-Rahman, Degritting of gluaconite clay by different techniques for use in water treatment and as fertilizer, Mineral Processing and Extractive Metallurgy (Trans. Inst. Min. Metall. C) 2006; 115(3): 145-149 https://doi.org/10.1179/174328506X109095

[8] Khaled A. Selim, Rasha Smair El-Tawil and Merit Rostom, Utilization of surface modified phyllosilicate mineral for heavy metals removal from aqueous solutions, Egyptian Journal of Petroleum 2018; 27: 393-401 https://doi.org/10.1016/j.ejpe.2017.07.003

Received on 3-3-2019 Accepted on 31-3-2019 Published on 22-5-2019

DOI: https://doi.org/10.31437/2414-2115.2019.05.3

© 2019 El-Rahman and Werther; Scientific Array This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.

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