Synthesis and Performance Evaluation of Newly Synthesized Waxy Crude Oil Dispersants and Inhibitors Using Styrene Based Copolymers

Wax crystallization is gaining special attention and there are various techniques applied to minimize the problems caused by paraffin wax deposition to facilitate pipeline transportation and increase the production of crude oil. The application of pour point depressants is an efficient way of inhibiting wax deposition. In this work, pour point depressant additives were synthesized by the copolymerization of tetradecene (TD) with styrene (S) at ratios (1:1) and (1:2). After alkylating the synthesized copolymers by Friedel Craft they were modified by esterification and amidation. The prepared additives were characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and gel permeation chromatographic analysis. Their performance as pour point depressants and paraffin inhibitors was explored. Various concentrations (500 ppm-2000 ppm) of tetradecene styrene ester and tetradecene styrene amide copolymers were injected into the collected waxy crude oil samples at 60 degrees C. The obtained data showed that adding the synthesized copolymers; ET1S1, ET1S2, AT1S1, and AT1S2 into the waxy crude oil samples with a dosage of 2000 ppm enhanced the pour point depressant via decreasing the pour point temperature (PPT) value from 27 degrees C (crude oil blank) to 15 degrees C, 15 degrees C, 15 degrees C, and 12 degrees C and achieved a paraffin inhibition of 67%, 70%, 71%, and 74%, respectively compared with the blank. The thermogravimetric study had shown good thermal stability for the esterified and amide copolymers as compared with their corresponding copolymers. So, the synthesized copolymers can be considered promising and applicable additives for depressing the pour point and inhibiting the paraffinic precipitates of the waxy crude oils.