Question $1(25$ marks$)$

$($a$)$ Describe the role$/$function of each of the following processes in a modern crude oil

refinery. In your descriptions, identify the feedstock and products in the process.

i$.$ Hydrotreating

$(4$ marks$)$

ii$.$ Catalytic cracking

$(4$ marks$)$

iii. Catalytic reforming

$(4$ marks$)$

$($b$)$ Briefly discuss the environmental impacts of a crude oil refinery, highlighting potential

sources and effects of air, water and land pollutants.

$($c$)$ The first step in LNG production is purification of natural gas. Identify the major

contaminants and explain why it is necessary to have these removed. $(7$ marks$)$