Study On The Desulfurization From FCC Diesel By Liquid Phase Selective Oxidation

With the decrease of crude oil resources, a lot of low quality crude oil which contains more sulfur compounds is exploitated which caused the increase of sulfur compounds in Fluid Catalytic Cracking diesel directly. Those sulfur compounds will make more sulfoxides, which are the main fact of environment pollution. With the increase of diesel engines, it is very time to do research on desulphudzation technology of Fluid Catalytic Cracking diesel. The demand of low-sulfur clean Fluid Catalytic Cracking is urgent.At early time, for the production of ultra low-sulfur fuel, hydrogen desulphurization should be taken such as high temperature, high hydrogen pressure, highly active catalyst and longer reaction time. Since the limitation above, working on non-hydrogen desulphurization took a great significance both on theoretical and practical. Among various methods, researcher focus on the selective oxide desulphurization because of low-level investment, simple process, mild process condition, obvious desulphurization effort. So we started selective oxide desulphufization research on Fluid Catalytic Cracking diesel and made a discussion on the air effort as oxidant.On normal atmosphere, we took the research on: hydrogen peroxide oxide desulphurization on Fluid Catalytic Cracking diesel, air oxide desulphufization on Fluid Catalytic Cracking' diesel and phase transfer catalysis oxide desulphurization. We investigated the influence on desulphurization rate caused by oxidization time, temperature, sort of catalyst accelerator, quantum of phase transfer catalysis, usage of phase transfer catalysis, and so on. And we analyzed the spectrum after oxide desulphurization. Then we made the conclusion as below:At oxide-extraction desulphurization,1. Without phase transfer catalysis, it's a contradiction between desulphurization rate and yisld while mass' use of extractant inceased the cost.2. With phase transfer catalysis, it can avoid the solvating effort between effictive oxide agent and catalyst. Otherwise, phase transfer catalysis can transfer the effictive oxide agent and catalyst to oil phase which promote oxide reaction and incease the desulphurization rate of Fluid Catalytic Cracking diesel.The final desulphurization process we chose is on condition of: air as oxide; phosphomolybdic acid phase transfer catalyst; at 50℃; 2 hours; air flow speed 120 L/h. Finally we got the reault were the desulphurization rate wae 88.2% and yield wae above 90%.