Simulation of Hydrodesulfurization (HDS) Thiophene in Naphtha over a Cobalt - Molybdenum Catalyst

The target of this paper is to simulate one of the main important treatment processes used in petroleum refinery, this process is the hydrodesulfurization (HDS) of naphtha. HDS is accomplished by converting sulfur compounds contained in naphtha to hydrogen sulfide (H2S) ; this is then removed as a gas by stripping. Generally, HDS used to reduce environmental pollution caused by sulfur dioxide (SO2) emission that result from various combustion practices and for pretreatment of catalytic reformer feeds to prevent sulfur poisoning of the catalysts. Cobalt–molybdenum on alumina supported (CoMo/Al2O3) is used as a catalyst. There are a wide range of models used to simulate HDS of naphtha. Three models have been chosen to simulate the process. These models were applied on three different types of Libyan crude, which are Es–Sider, Brega, and Hamada crude. A computer program used to simulate the models for HDS process. The results shows that all models gives the conversion of thiophene to be greater than 90 %. That means the HDS product contains as maximum as 5 ppm of sulfur which is suitable to be feedstock for catalytic reforming process. Model 1 gives the best prediction of HDS reactor performance for specified operating conditions (temperature and pressure).