表面活性剂同系物体系对原油界面张力的影响

分别从表面活性剂的亲油性和亲水性的二种性能 ,研究了复配型表面活性剂的性能及规律。在表面活性剂同系物复配的研究中 ,得出相对分子质量分布窄的表面活性剂不能与原油形成低的界面张力 ,但两种以上相对分子质量分布窄的表面活性剂按一定比例混合后 ,则可以与大庆原油形成超低界面张力。形成超低界面张力的表面活性剂平均当量范围为 410～ 430 ,相对分子质量、碱浓度和界面张力三者之间有一定规律 ,即表面活性剂平均相对分子质量增加 ,界面张力曲线向低浓度碱方向移动 ;平均相对分子质量降低 ,界面张力曲线向高浓度碱方向移动。相对分子质量分布是影响界面张力的又一因素 ,表面活性剂相对分子质量分布、原油中的碳数分布和界面张力可能存在某种特定联系。支链对降低界面张力方面比直链有更好的效果 ,表面活性剂相对分子质量越高 ,则油砂对其吸附量越大

Effect of Surfactant Homologue System on Oil-water IFT

We studied the hydrophile and hydrophobe properties of mixed surfactant. The study shows that surfactant which has narrow molecule weight (MW) could not form ultra-low interfacial tension (IFT) with Daqing crude oil ,but two or more kinds of surfactant of narrow MW mixed with certain ratio could.The equivalent range of surfactant, which form ultra-low IFT, is 410-430. IFT curve move towards low alkali concentration as average molecule weight increases, while IFT curve move towards high alkali concentration as average molecule weight decreases. The distribution of molecule weight is another factor that affects the IFT. There might have some relationship between surfactant molecule weight, the carbon number in the oil and the interfacial tension. Branched chain is more effective to decrease IFT than straight chain, the adsorption of surfactant on oil sand increase as the molecule weight increases. The study is helpful to the surfactant production and reformulation.