Synthesis and Research of Highly Efficient Polyether Demulsifier

Separation of oil and water has always been a top priority in the oil industry. In this study, bisphenol A phenolamine resin (BPA) was synthesized from bisphenol A, diethylenetriamine and formaldehyde. With KOH as a catalyst, the initiator, ethylene oxide (EO) and propylene oxide (PO) were polycondensed into triblock polyethers with different molecular weights, and then crosslinked to increase the molecular weight. The target product was determined by (HNMR)-H-1 and FT-IR, and the synthesis process of triblock polyether demulsifier was optimized by changing the ratio of initiator to head PO, PO to EO and head PO to tail PO. Then, the important influential factors for the demulsification such as the demulsifier concentration, standing time, temperature, pH and Hydrophile-lipophile balance (HLB) values were investigated. The results suggestted that the optimal synthesis ratio of BPA type triblock polyether demulsifier was as follows: initiator/PO = 1: 109, PO/EO = 2: 1, head PO/tail PO = 1: 3. Under demulsification conditions, the dehydration temperature was 50 degrees C, the dosage was 75 mg.L-1, pH was 7.6 and HLB was 9.1, and the dehydration rate reached 92.5% in 90 minutes. Compared with the existing demulsifier, the demulsifier has a lower demulsification temperature and higher demulsification efficiency. Therefore, it can be concluded that the polyether demulsifier has potential application for the crude oil dehydration, and the current work may be helpful to explore the demulsification development.