Development of Poly(acrylate-co-benzyl maleate) Copolymers as Wax Deposition Inhibitors for Crude Oil

Wax precipitation and deposition during crude oil transportation through pipelines pose significant flow assurance challenges. Therefore, the present work focuses on synthesizing a range of poly(C22Ac-co-BM) copolymers (P1, P2, and P3) derived from fatty alcohol acrylate (C22Ac) and benzyl maleate (BM) through free radical polymerization (FRP). These copolymers were designed to serve as efficient wax inhibitor (WI) additives for crude oil. The detailed characterization of these additives was carried out using structure-sensitive techniques, such as 1H–13C nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and gel permeation chromatography. The paraffin inhibition efficiency (% PIE) of these additives was investigated using pour point, coldfinger, and flow loop experiments. The findings revealed a pour point reduction of branched line crude oil (BLCO) doped with P1, P2, and P3 ranging from 17 to 67% and wax inhibition between 40 and 68% at an optimal dosage of 400 ppm. Among the synthesized poly(C22Ac-co-BM) copolymers, P2 displayed the most promising performance, demonstrating a 67% reduction in the pour point and a substantial 69% reduction in BLCO wax deposition.