3. Coker naphtha is hydrotreated to remove 80% of the sulphur, 60% of the nitrogen and all the olefins. Sulphur is present as thiophene and nitrogen as pyrrole. The naphtha has the following properties: Specific gravity: 0.763 , sulphur: 1.7wt%, nitrogen: 200 wppm, propylene: 0.2wt%, butanes: 3.5wt% and butadienes: 0.3wt%. (a) Find the chemical hydrogen requirement for one barrel of naphtha. (b) Make a material balance around the hydrotreater and find the hydrotreated naphtha API