A. Increased biuret formation
B. High corrosion rate
C. Increased cost of equipment
D. All A., B. & C.
Related Mcqs:
- Lower temperature and large excess of ammonia in urea melt__________________?
A. Increases biuret formation
B. Decreases biuret formation
C. Is undesirable
D. Does not effect biuret formation - Prilling of urea should be accomplished (in a sprayer) just above the melting point of urea with minimum of retention time, otherwise it will result in__________________?
A. Low bulk density product
B. Biuret formation
C. Non-spherical prills
D. Substantially wet non-flowing and sticky product - During conversion of ammonium carbamate into urea, presence of large excess of water______________?
A. Increases the yield of urea
B. Adversely affects the yield of urea
C. Reduces the evaporator load by diluting the urea solution
D. Does not affect the yield of urea - The composition of fresh feed to the high temperature, high pressure urea autoclave is______________________?
A. Excess liquid ammonia and liquefied CO2
B. Excess liquid ammonia and compressed CO2 gas
C. Liquid ammonia and excess compressed CO2
D. Compressed ammonia gas and excess compressed CO2 - Temperature and pressure in urea autoclave is_________________?
A. 120°C and 300 atm
B. 190°C and 200 atm
C. 400°C and 550 atm
D. 200°C and 10 atm - Dehydration of ammonium carbamate to yield urea is a/an __________________ reaction?
A. Exothermic
B. Endothermic
C. Autocatalytic
D. Catalytic - Temperature and pressure in ammonia converter is_________________?
A. 200 atm, 1000°C
B. 450 atm, 200°C
C. 450 atm, 550°C
D. 450 atm, 1000°C - Which of the following set of conditions is favourable for the maximum yield of ammonia by Haber’s process ?
A. High pressure, low reactants concentration, high temperature
B. High pressure, low reactants concentration, low temperature
C. High pressure, high reactants concentration, low temperature
D. Low pressure, high reactants concentration, low temperature - ____________ catalyst is used in the production of urea from CO2 and NH3?
A. Vanadium pentoxide
B. No
C. Alumina
D. Nickel - Though kinetics of ammonia synthesis dictates the use of low temperature for high equilibrium conversion, yet it is kept moderately high (550°C), because at low temperature___________________?
A. Rate of reaction is very low
B. Very high pressure is required resulting in costly pressure vessel
C. Space velocity of gas is very low resulting in decreased conversion
D. None of these
