Explain methods for industrial preparation of alcohol.

The important methods for the preparation of alcohol on large-scale are given below:
    
By hydration of Alkenes

Alkenes are obtained by cracking of petroleum. They are easily converted to alcohols by the addition of water in presence of sulphuric acid.
                                 
1907_alcohol preparation.png 

In case of unsymmetrical alkenes, the addition takes place according to Markowniko's rule.
                          
681_alcohol preparation1.png 
    
By fermentation of carbohydrates

Formation of ethyl alcohol by the fermentation of sugar (obtained from molasses, grapes or beet) is one of the oldest methods. Sucrose is first of all changed to glucose and fructose with an enzyme invertase.
                                
1330_alcohol preparation2.png 

Enzyme zymase after that converts glucose and fructose into ethanol.

The enzyme zymase is present in yeast.
                              
65_alcohol preparation3.png 

The fermentation procedure is taken out under anaerobic conditions i.e. in the nonexistence of air. Carbon dioxide released during fermentation keeps the fermentation mixture out of contact of air. If the fermentation mixture gets exposed to air, the oxygen of air oxidizes ethanol to ethanoic acid which makes the mixture sour.

Ethanol is obtained from starchy materials such as barley, rice, maize and potatoes with enzymes diastase and maltase.
                        
1057_alcohol preparation4.png 

Enzyme diastase is obtained from germinated barley while enzyme maltase and zymase are obtained from yeast.
    
Oxo process

Alkenes react with carbon monoxide and hydrogen in the presence of Octacarbonyl dicobalt Co[CO]
                       
1121_alcohol preparation5.png

   Related Questions in Chemistry

  • Q : Depression in the freezing point When

    When 0.01 mole of sugar is dissolved in 100g of a solvent, the depression in freezing point is 0.40o. When 0.03 mole of glucose is dissolved in 50g of the same solvent, depression in the freezing point will be:(a) 0.60o  (b) 0.80o

  • Q : What is schrodinger wave equation? The

    The Schrodinger wave equation generalizes the fitting-in-of-waves procedure.The waves that "fit" into the region to which the particle is contained can be recognized "by inspection" only for a few simple systems. For other problem a mathematical procedure

  • Q : Problem based on molarity Select the

    Select the right answer of the question. If 18 gm of glucose (C6H12O6) is present in 1000 gm of an aqueous solution of glucose, it is said to be: (a)1 molal (b)1.1 molal (c)0.5 molal (d)0.1 molal

  • Q : Problem on making solutions The weight

    The weight of pure NaOH needed to made 250cm3 of 0.1 N solution is: (a) 4g  (b) 1g  (c) 2g  (d) 10g Choose the right answer from above.

  • Q : Production of alcoholic drinks give all

    give all physical aspects in the production of alcohol

  • Q : Product of HCl Zn Illustrate  the

    Illustrate  the product of HCl Zn?

  • Q : Formula of diesel Write a short note on

    Write a short note on the formula of diesel, petrol and also CNG?

  • Q : Calculation of molecular weight Provide

    Provide solution of this question. In an experiment, 1 g of a non-volatile solute was dissolved in 100 g of acetone (mol. mass = 58) at 298K. The vapour pressure of the solution was found to be 192.5 mm Hg. The molecular weight of the solute is (vapour pressure of ace

  • Q : Problem on partial pressure i) Show

    i) Show that the equilibrium constant Kp for the reaction CaCo3(s) ↔ CaO(s) +CO2(g)is about unity (i.e. = 1.0) at 895 °C.ii) If two grams of calcium carbonate are pl

  • Q : Anti-aromatic and the non-aromatic

    What is main difference among anti-aromatic and the non-aromatic compounds?

©TutorsGlobe All rights reserved 2022-2023.