The Research On Removal Of Ni And V In Oman Crude Oil By Cr³⁺ Under NaBH₄Mild Hydrogenation

The presence of Ni and V causes many serious problems during crude oil processing, and the removal of them has alway been a important reserach topic. In order to remove Ni and V in Oman Crude Oil and reduce the influence of Ni and V on the subsequent crude oil processing, NaBH4was employed to simulate the hydrogenation operation in this thesis. The optimal experimental parameters and the collecting effect of Cr3+on Ni and V were investigated, and the experiment mechanism was also explored. At the end of this thesis, some other removal techniques were tested on Oman oil. The main results and conclusions are as followed:(1) Under the NaBH4mild hydrogenation condition, Cr3+has a obvious collecting effect on nickel and vanadyl porphyrins in oil model. The best operating condition for the experiment is determined through experiments:under the temperature of150℃, addition of0.470μL NaBH4solution in every50mL Oman Crude Oil (the concentration is1.5625g/25mL DMF). After homogeneous mixing process,0.280μL of CrCl3·6H2O(the concentration is4.6128g/25mL DMF) is added into the mixture and the optimal reaction time is6hours. With this operating condition, the removal of Ni and V is71%and74%, respectively.(2) The reaction mechanism concerning the influence of Cr3+under NaBH4mild hydrogenation simulation shows that with the condition described above, after the etioporphyrin nickel outer ring’s C-C hydrogenation, the N-Ni bond connecting Ni is broken in nickel-porphyrin. Compared to Ni2+, Cr3+has a stronger binding energy with etioporphyrin, and hence releasing Ni from the organics.(3) The above experiments could be strengthened under microwaving. The removal of Ni reaches as high as95.29%and the highest rate of V is96.55%.