Demulsification of crude oil emulsion using carbonized cotton/silica composites

Abstract

Abstract As a substitute for conventional oilfield chemicals, biomass-based composite materials have received extensive attention. In this study, degreasing cotton (DC) and tetraethyl orthosilicate (TEOS) were used as raw materials to synthesize carbonized cotton coated with SiO2 (CC@SiO2). CC@SiO2 was characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray spectroscopy (XRD), field-emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectrometer (EDS). The effect of vital factors such as CC@SiO2 dosage, settling time and temperature on the demulsification performance was investigated. The optimal demulsification efficiency (DE) could reach 90.38% after demulsifying with 400\xa0mg/L of CC@SiO2 at 65 ℃ for 120\xa0min. The demulsification mechanism was studied by investigating the dynamic interfacial tension (IFT), interfacial activity and wettability. Additionally, the flocculation and aggregation of water droplets and separation of oil-water in emulsion were observed by the optical microscope. The current work indicates that CC@SiO2 is a simple, high-efficient demulsifier for the separation of the water-containing crude oil, which shows a good application prospect in oil industry.