Effect of Spacer Length between Phenyl Pendant and Backbone in Comb Copolymers on Flow Ability of Waxy Oil with Asphaltenes

Role of surfactants, polymers, nanoparticles, and its combination in inhibition of wax deposition and precipitation: A review

Oil wax deposition and precipitation are becoming a major problem during oil production, transportation, and refining. Deposition mitigation by chemical additives, like polymer and surfactants, are commonly used in the oil industry. Because there is no clarity in wax inhibition mechanisms of the additive with crude type and conditions, chemical wax inhibitors are still used in a trial-and-error manner in the oil fields, which is an expensive and inefficient methodology. Understanding the wax inhibition mechanism is important for the design of new inhibitors. This review aims to give an overview of the understanding and development of nanoparticle technology, surfactants, polymer, and their combination in the inhibition of wax deposition. The review looks into lab and pilot plant experiments reported in the recent literature, with more focus on the fundamentals of nanohybridization approaches in wax deposition control, testing methodologies (i.e., thermal, rheological, and morphological analysis), inhibition performance assessment, and mechanisms. The review begins with an overview of bibliometric analysis to shed light on the emerging areas in that field and also explore and analyze the large volumes of scientific data reported from 2000 to 2022 in this field. The performance parameters used for assessing the wax inhibitors in the laboratory are also summarized and addressed. Finally, the challenges and future remarks of the reported chemical inhibitors are reported in this paper. This review provides insights into the integration of nanomaterials into the existing technologies to overcome the existing challenges.

Comparative Study between a Copolymer Based on Oleic Acid and Its Nanohybrid for Improving the Cold Flow Properties of Diesel Fuel

The as-synthesized copolymer based on the prepared monomers and its nanohybrid were used for improving the cold flow of diesel fuel that has a vital role in meeting energy needs. The copolymer (AE) was created using the prepared monomers, by free radical solution polymerization of the prepared hexadecylmaleamide and octyloleate ester, and the polymer nanohybrid (NH) was created by emulsion polymerization of the same monomers with 1% nano-SiO₂. The chemical structures of the copolymer and its nanohybrid were proved by Fourier transform infrared spectroscopy (FTIR), ¹H NMR, dynamic light scattering (DLS), and transmission electron microscopy (TEM). Through exploring the effect of the nanohybrid, before and after adding the dosage of the additives to the diesel fuel, the pour point temperature (PPT), rheological characteristics, and viscosity index were measured. The data were the best for the nanohybrid; the PPT decreased from -3 to -36 °C upon adding 10,000 ppm nanohybrid but decreased from -3 to -30 °C for 10,000 ppm copolymer. In addition, the efficiency of the additives was proved by viscosity-shear rate and shear rate-shear stress curves to give the apparent viscosity, which decreased from 124 cP for the blank to 15.74 and 12.8 cP for AE and NH, respectively; also, the yield stress decreased from 576 D/Cm² for the blank to 541.44 and 477.9 D/Cm² for AE and NH, respectively, at room temperature. The viscosity index increased from 116 for the blank to 119 and 121 for the copolymer and the nanohybrid, respectively. Polarizing optical microscopy was performed to show more tiny and separated wax upon adding the additives. The findings showed that delayed crystal precipitation and altered crystal shape with the NH and AE greatly reduced low-temperature viscosity and enhanced the cold flow characteristics of the diesel fuel.