Study On The Isolation And Enrichment Of Different Porphyrins In Petroleum And Effects On Catalytic Cracking Process

Comprehensive ways of processing heavy oil, inferior oil and residual oil have great significance on enhancing the depth of crude oil processing, increasing the economic benefits of oil processing and improving the integrated quality of refined oil.The method on separation and enrichment of metal porphyrins has been studied. The Venezuela 380 oil and Yichang tube-transporting oil residue were used as research object. And the methods of solvent extraction and column chromatography separation were employed to separate the different metall porphyrins. After enrichment, the concentration of nickel and vanadium porphyrins were raised 33 and 77 times respectively in Venezuela 380 oil, and also 92 and 108 times respectively in Yichang tube-transporting oil residue.There was a large part of the metal compounds existed as non-porphyrins in heavy oil, the method of its separation was studied. Venezuela 380 oil was employed as the research object, and two steps extraction which firly with solvent of acetonitrile and secondly DMF was used to isolated the metal non-porphyrin compounds which molecule is smaller.The impacting of metal porphyrins in Venezuela crude oil and Yichang tube-transporting oil residua on the product distribution and catalyst properties of catalytic cracking process was inspected. The results showed that in the conditions that catalysts used in each experiment was fresh, the trend of the product's yield changed with the vanadium porphyrins content was much flatter, which means that nickel porphyrins had greater impaction on the reaction selectivity; Through the results of the catalyst recycling experiment, nickel porphyrin had smaller destructive effect on the catalytic activity. In the process of catalyst cracking, vanadium porphyrins were much easier to be demetalised. Metal had an oxidation reaction in catalyst regeneration process, generated NiO and V2O5. NiO prevented the contaction of fuel oil and the catalytic activity center, whereas V2O5 had a reaction with the active center of zeolite which resulted the permanent deactivation of the catalyst.