ETHYL ALCOHOL

-Prepared ByMehul Mehta (13BCH034)Dhruv Mewada (13BCH035)

INTRODUCTION

• Molecular formula : C2H6O

• Molar mass : 46.07 g/mol• Density : 0.789 g/cm3 (at 25oC)• Boiling point : 78.37oC• Melting point : -114.3oC• Flash point of pure ethanol : 16.60oC• Stable but highly flammable

Flammability• The flash points of ethanol concentrations from 10% ABV to 96%

ABV are shown below:

• 10% — 49 °C (120 °F)• 20% — 36 °C (97 °F)• 30% — 29 °C (84 °F)• 40% — 26 °C (79 °F)• 50% — 24 °C (75 °F)• 60% — 22 °C (72 °F)• 70% — 21 °C (70 °F)• 80% — 20 °C (68 °F)• 90% — 17 °C (63 °F)• 96% — 17 °C (63 °F)

• Alcoholic beverages that have a low concentration of ethanol will burn if sufficiently heated and an ignition source (such as an electric spark or a match) is applied to them. For example, the flash point of ordinary wine containing 12.5% ethanol is about 52 °C 

PREPARATION METHODS

• From biomass like sugar, starch and cellulose

• Sulfuric acid process• Phosphoric acid process• From acetylene

FROM BIOMASSsugar ethanol

starch sugar ethanol

cellulose and hemi-cellulose ethanol

ETHANOL PRODUCTION

• About 60% of global bioethanol production are obtained from sugar cane and 40% from other crops

FEEDSTOKE• North America : corn, wheat• South America : sugar cane• Europe : wheat, sugar beet, waste from the wine industry

From wheat

Fermentation conditions

Temperature - 32˚C and 35˚C pH - 5.2.

Ethanol is produced at 10-15% concentration and the solution is distilled to produce ethanol at higher concentrations

From sugar cane

• Simplest of all the processes• Cheap method

• From cornThe main producer - United

States

• Wet milling

– The process of separating the corn kernel into starch, protein, germ and fiber in an aqueous medium prior to fermentation.

– The primary products • starch and starch-derived products (e.g. high fructose corn

syrup and ethanol) • corn oil, corn gluten, etc..

• Dry milling

– The entire corn kernel is first ground into flour and the starch in the flour is converted to ethanol via fermentation.

– Other than ethanol• carbon dioxide - carbonated beverage industry • distillers dried grain with solubles (DDGS) - animal feed

• Malting

– Steep the corn in water, start germination, stop germination at a particular by drying to stop further growth.

FERMENTATION OF SUGAR

+Invertase

Or

Zymase 2C2H5OH + 2CO2

CELLULOSIC ETHANOL

• Ethanol made from cellulosic biomass which comprises the stems and branches of most plants.

• The other feedstock to produce ethanol can also be used as food so cellulosic ethanol is an alternative feedstock.

• It is expensive compare to other method but as the technology has developed the method has become cheaper

CONVERSION OF CELLULOSE AND HEMICELLULOSE TO

ETHANOL• 4 steps1. Pretreatment2. Hydrolysis3. Fermentation4. Distillation of the product mixture to

separate ethanol

ETHANOL FROM ACETYLENE

H-C = C-H + H2O CH3CHO

Acetylene Acetaldehyde

CH3CHO + H2 C2H5OH

Acetaldehyde Ethanol

_

H2SO4

HgSO4

Ni∆

PHOSPHORIC ACID PROCESS

CH2=CH2 + H2O C2H5OH

Ethene Ethanol

• Phosphoric acid process was first used commercially by Shell (USA) in 1947.

• In this reaction phosphoric acid is used as catalyst.

• For this process yield of ethanol is 95%.

H3PO

4300oC60 atm

SULFURIC ACID PROCESS

CH2=CH2 + H2SO4 CH3-CH2-OSO3H

Ethene Ethyl hydrogen sulphate

CH3-CH2-OSO3H + H2O C2H5OH + H2SO4

Ethyl hydrogen Ethanol sulphate

• Sulfuric acid process involves indirect hydration.• For this process yield of ethanol is 90%.

75o

C

Mechanism

CH3CH2SO4H + H-OH

CH3CH2OH +H2SO4

Ethanol

Ethyl hydrogen salphate

PRODUCING COMPANIES

• Gujarat1) Tomsa Distil India Ltd.2) A. B. Enterprise

• India1) Sarat Pvt. Ltd. (AP)2) Bajaj Hindustan Ltd. (UP)

• Global1) Green Field Ethanol (Canada)2) Logen Co. (Canada)