Spherical polymer brushes bearing imidazole groups as novel nickel remover for crude oil

Nickels in crude oil often deactivate the hydrocracking and catalytic cracking catalysts. Strong acids are widely applied to remove these nickels, although they cause severe corrosion to the subsequent catalytic cracking and processing equipment. Polymer brushes bearing specific groups which can adsorb nickel ions are considered as desirable non-corrosive nickel removal agents. In this work, micro-sized spherical polymer brushes bearing imidazole groups (PVIm@SiO2) are first applied to remove trace nickels in crude oil with the help of electric demulsification. The effects of polymer brushes concentration, oil/water ratio and electric demulsification temperature on nickel removal efficiency are investigated. Compared with the monomer (VIm) and polymer (PVIm) bearing imidazole groups, polymer brushes exhibit a much higher nickel removal efficiency than the other two, which is approximately 66.7%. In addition, the regeneration of polymer brushes are achieved by a rapid and simple process using diluted HCl. As well as, the removal efficiency of Ni remains 62.5% in 5 consecutive cycles. Consequently, these spherical polymer brushes bearing imidazole groups are reasonable nickel remover for crude oil.