Along with worldwide problem of the inferiority and heavilization of crude oil, the impact of high levels of nickel and vanadium in crude oil on petroleum processing are becoming more and more severe. Thus more and more attentions are paid to study on removing nickel and vanadium from crude oil. This article takes the transition metal nickel and vanadium organic compound in inferior crude oil as the research object. Synthesis and modification of natural and biodegradable polymers containing coordinating groups are discussed in details, and tubular continuous microwave equipment and tank microwave pulses equipment were adopted in the experiment. Research on removing nickel and vanadium from crude oil in its pretreatment rocess under microwave irradiation were conducted. The effect of microwave on the distribution of nickel and vanadium in crude oil before and after microwave treatment was analyzed. The effect of microwave and demetallizers on nickel and vanadyl porphyrins in oil model was studied by UV spectroscopy and Raman spectrum method. Removing nickel and vanadium from crude oil under microwave irradiation was studied and the mechanism was investigated. The results showed that:Four CTS derivatives, such as DTC-CTS, C-CTS, V-CTS and CM-CTS, were synthesized using chitosan CTS-50 as raw material and CTS derivatives showed more effective removal of nickel and vanadium from crude oils. CM-CTS was characterized by having more coordination group and smaller steric hindrance of the reactions with nickel and vanadium in crude oil. The synthesis optimization of CM-CTS series of carboxymethyl chitosan using the orthogonal experiment was investigated in this paper, CTS-50 carboxymethyl process was occurred using the most suitable factor combination and CM 10 was synthesized. Infrared spectroscopy of CM 10, CM10-Ni and CM10-VO indicated that the -NH- and -COO- group also reacted with the nickel ions and vanadium ions. CM 10 was observed with scanning electron microscopy, the results showed that the CM 10 exhibits a wavy surface and a nanosized porous network structure with randomly distributed gaps on the surface of CM10. This porous structure and the gaps increased the CM10 surface area, and this could help CM10 adsorbing nickel ions and vanadium ions. The structure of starch was modified and altered, so that SC and SX series products were obtained. SC5 (the degree substitution was 2.0) showed the best effective in SC series products. Also, the -O-CSS- coordinating groups have stronger complexing action with nickel and vanadium in crude oils in SX series products, so SX series products showed more effective removal of nickel and vanadium from crude oils. The synthesis optimization of SX series products using the orthogonal experiment was investigated in this paper, and SX10 was synthetized. The particles in decentralized system were adsorbed by function groups in long chains of carbon of starch-based polymer SX10, SX10 was characterized by having coacervationand net-capture function, so the complex compounds which was obtained by chelation between SX10 and nickel and the vanadium ions in the crude oil have been fallen down rapidly.Tubular continuous microwave equipment and tank microwave pulses equipment were adopted in the experiment. The effects of microwave, CM 10 and SX10 dosage on the removal of nickel and vanadium from crude oil were investigated. Under the condition that the microwave power was 300 W, microwave time was 2 min, initial temperature was 60℃, reaction temperature was 85℃, reaction time was 20 min and CM10 or SX10 dosage was 400 mg/L, as to CM 10, nickel and vanadium removal efficiencies from Guanshu crude oil were 77.17% and 83.95% respectively, nickel and vanadium removal efficiencies from Beijiang crude oil were 80.77% and 86.34% respectively, nickel and vanadium removal efficiencies from Xibeiju crude oil were 84.79% and 90.24% respectively, as to SX10, nickel and vanadium removal efficiencies from Guanshu crude oil were 79.05% and 86.98% respectively, nickel and vanadium removal efficiencies from Beijiang crude oil were 82.61% and 89.25% respectively, nickel and vanadium removal efficiencies from Xibeiju crude oil were 85.88% and 91.53% respectively. The nickel and vanadium removal efficiencies from crude oil can be increased by increasing the duty cycle. At a duty cycle above 5:10, there was no further increase in nickel and vanadium removal efficiencies. When microwave pulses time was 60 S and SX10 dosage was 200 mg/L, nickel and vanadium removal efficiencies from Guanshu crude oil were 66.75% and 77.36% respectively, nickel and vanadium removal efficiencies from Beijiang crude oil were 72.90% and 80.52% respectively, nickel and vanadium removal efficiencies from Xibeiju crude oil were 79.42% and 84.68% respectively. CM10 and SX10 have a good effect on removal of nickel and vanadium from crude oil under microwave reinforcing action.The effects of microwave on the distribution of nickel and vanadyl porphyrins in crude oil and metal content appeared in M-asphaltene were investigated. The effect of microwave on vanadyl porphyrins is stronger than that of nickel porphyrins, nickel porphyrins have better chemical stability than vanadyl porphyrins. The sequence from strong to weak of microwave effects was:VO-ETIO>VO-DPEP, Ni-ETIO>Ni-DPEP. The electron donating abilities for central metal ions of M-DPE was stronger than that of M-ETIO in nickel and vanadyl porphyrins compound, the complex with DPEP and central metal ions has better chemical stability than that of the complex with ETIO and central metal ions. Nickel and vanadium contents in the form of M-asphaltene decreased remarkably after microwave. The mechanism of the effect of microwave on nickel and vanadium organic compound in crude oil was investigated. The effect of microwave and demetallizers on nickel and vanadyl porphyrins in oil model was studied by UV spectroscopy and Raman spectrum method. Therefore, it can be concluded that the coordinating groups of chitosan polymers CM10 and starch based polymers SX10also reacted with the Ni2+ and VO2+ of NiOEP and VOOEP. So microwave, CM 10 and SX10 showed more effective removal of nickel and vanadium from oil model. |