Wax deposition from crude oil that blocks the pipeline and increases the viscosity of the fluid is considered as a serious challenge for petroleum transportation. Employment of chemical additives, the so-called pour point depressants (PPDs), is widely used to solve this problem. Among them are the ethylene-vinyl acetate (EVA) copolymers (EVAc), containing a polyethylene segment along the backbone with vinyl acetate. To improve the performance of EVAc as PPD, the compositions of this polymer with crude gossypol (CG), isolated from the refined cottonseed oil soapstock, were prepared by joint milling in a ball mill. Prepared compositions were characterized by Fourier transform infrared (FTIR), ultraviolet (UV), and nuclear magnetic resonance (NMR) spectroscopy. The pour point and viscosity of the crude oil from the Akshabulak oil field (Kazakhstan) were studied. The compositions with 10, 20, and 25 wt% of CG demonstrate better efficiency as PPD for crude oil than EVAc at the dosage of PPD of 50, 100, 250, and 500 ppm. The improved properties of the obtained PPD in comparison with the commercial EVAc is explained by the appearance of additional nonpolar and polar groups caused by the formation of the EVAc/CG composition.

中文翻译：

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乙烯-醋酸乙烯酯共聚物/粗棉酚组合物作为蜡质油的降凝剂

原油的蜡沉积会阻塞管道并增加流体的粘度，这被认为是石油运输面临的严峻挑战。化学添加剂的使用，即所谓的降凝剂（PPDs），被广泛用于解决这一问题。其中有乙烯-乙酸乙烯酯（EVAc）共聚物（EVAc），该共聚物在主链上含有一个带有乙酸乙烯酯的聚乙烯链段。为了提高EVAc作为PPD的性能，通过在球磨机中联合研磨，制备了从精制棉籽油皂料中分离的具有粗棉酚（CG）的聚合物组合物。制备的组合物通过傅里叶变换红外（FTIR），紫外（UV）和核磁共振（NMR）光谱进行表征。研究了来自阿克沙布拉克油田（哈萨克斯坦）的原油的倾点和粘度。在50、100、250和500 ppm的PPD剂量下，含10、20和25 wt％CG的组合物对原油的PPD效果优于EVAc。与市售的EVAc相比，获得的PPD的性能改善是由于由EVAc / CG组合物的形成引起的另外的非极性和极性基团的出现。