Petroleum Refinery Engineering

A. With increase in the reactor pressure, octane number of gasoline decreases
B. With increase in the reactor temperature, gasoline yield decreases for a given conversion
C. Percentage conversion increases with increase in the catalyst to oil ratio
D. All A., B. and C.

A. Moderate changes in operating temperature does not change the depth of cracking
B. Increased residence time results in the decreased severity of cracking
C. At low pressure, the yield of lighter hydrocarbons are more
D. Greater depth of cracking gives lower octane number gasoline

A. Iso-paraffin crack faster than n-paraffin.
B. Catalytic cracking is endothermic, but the regeneration of catalyst is exothermic
C. Rate of decomposition of olefins in catalytic cracking is slightly slower than the thermal cracking
D. None of these

A. Pensky-Marten apparatus is used for determining flash points above 50°C
B. Characterisation factor of paraffinic crude oil is more than 12
C. Abel apparatus is used for determining flash points below 50°C
D. An oil having high susceptibility to change in viscosity with temperature changes, has a high viscosity index

A. Aromatics have higher specific gravity than paraffins
B. Gross calorific value (GCV) of petrofuels is equal to (12400 – 2100 ρ2) where, ρ is the specific gravity of the fuel at 15.5°C
C. Heavier petrofuels have higher GCV on weight basis (i.e., Kcal/kg) but lower GCV on volume basis (i.e., Kcal/litre)
D. Higher specific gravity of petrofuels means higher C/H ratio

A. Octane number of i-octane is zero
B. Octane number of paraffins increases with increasing number of carbon atoms
C. Branched chain paraffins have higher octane number than straight chain paraffins with same number of carbon atoms
D. The aromatics have lower octane number than naphthenes with same number of carbon atoms

A. Coking tendency increases with increasing molecular weight
B. Coking tendency decreases with increasing molecular weight
C. Higher pressure enhances coke formation
D. Coking is an exothermic reaction

A. Paraffins have higher octane number than corresponding iso-paraffin
B. Paraffins have lower smoke point than aromatics
C. Suitability of kerosene as a fuel & as an illuminant may be determined by char value test
D. Aviation fuel should have very high cloud point

A. Multigrade lubricating oils have high viscosity index
B. Paraffinic oil has very high viscosity index
C. Naphthenic oil has very low viscosity index
D. High viscosity index means a large change in viscosity with change in temperature

A. Depress its pour point
B. Dissolve wax
C. Precipitate wax
D. Remove wax