丙烯酸聚合物刷脱除原油中卟啉镍的实验研究

Experimental Study of Polyacrylic Acid Brush Removal of Nickel Porphyrin From Crude Oils

为探寻高效、无腐蚀的原油脱镍剂,以SiO2为核、聚丙烯酸(PAA)为壳,利用自由基调聚法,合成具有核-壳结构的聚合物刷(PAA@SiO2)。通过红外光谱、热重分析和扫描电镜对PAA@SiO2进行了表征,并结合电脱盐工艺考察了PAA@SiO2对原油中卟啉镍的脱除效果,分析了原油中卟啉镍的脱除机理。结果显示:合成的PAA@SiO2中PAA的接枝质量分数和摩尔质量分别达到7.03%和351.5g/mol;当PAA@SiO2脱镍剂用量为6000μg/g、水/油质量比为0.08、电脱盐温度为125℃、电脱盐低压场强为600V/cm、高压场强为1200V/cm时,3次连续脱镍实验后的原油脱镍率高达89.9%。因此,核-壳结构的PAA@SiO2聚合物刷可有效脱除原油中的金属镍,为原油脱金属剂的结构设计提供了新思路。

To efficiently remove Ni from crude oils and also without corrosion occurring in the process,polymer brush with core-shell structure(PAA@SiO2)was synthesized by radical polymerization,in which micro-sized SiO2 as the core and polyacrylic acid as the shell.The synthesized materials were further characterized with Fourier transform-infrared spectrometer,thermogravimetric analysis and scanning electron microscope.Effect of PAA@SiO2 on Ni porphyrin removal was studied and Ni removal mechanism was discussed.Experimental results suggested that,for the synthesized PAA@SiO2,the grafting mass fraction and calculated molecular mass of PAA are 7.03%and 351.5 g/mol,respectively.Under the conditions of PAA@SiO2 doses is 6000μg/g,water/oil mass ratio is 0.08,electric desalting temperature is 125℃,low-voltage field strength is 600 V/cm and high-voltage field strength is 1200 V/cm,Ni removal ratio can be 89.9%after three times continuous removal processes.Experimental study indicates that PAA@SiO2 with core-shell structure can effectively remove Ni from crude oils.Thus this study provides a different strategy for new materials which can be used as crude oil demetalization.