Two-stage coking of sour feedstocks

Abstract

1. It has been shown that one of the methods for producing cokes with lower sulfur contents from sour feedstocks is pretreatment or proper selection of feedstock. 2. Two-stage coking has been studied with two sour extracts of different origin. It has been shown that the coke/feedstock ratios of sulfur content are 1.24 and 0.98 for the first-stage coking of these extracts, but are reduced to 0.6 and 0.47 in the second-stage coking. 3. On the basis of the chemical group composition of the coker feedstocks, it can be postulated that the sulfur compounds present in the chromatogrpahic fractions of heavy aromatic hydrocarbons are less resistant to thermal breakdown than the sulfur compounds in the light and medium aromatic hydrocarbon fractions.