Abstract: Hydrocracking is an important technology for maximizing reforming feedstock naphtha production. The influence factors of the reaction process were studied. The results show that the heavy naphtha yield is increased, but the heavy naphtha selectivity and potential aromatics content are reduced with increasing of conversion degree. While the changes of hydrogen partial pressure within the test range have little impact on those features. The heavy naphtha selectivity and potential aromatics content are improved by cycling the unconverted oil. The yield of heavy naphtha reaches up to 68% by this operation mode. Based on the test results, a 1 500 kt/a hydrocracking unit was built in Taizhou petrochemical Co. where the recycling mode for increasing naphtha and diesel suggested by RIPP was applied. The technology could meet the demands of reforming feedstock and clean diesel.

Key words: hydrocracking, naphtha, reforming feedstock