【摘要】 通过硅烷偶联剂KH550和十八酸对纳米SiO₂进行复合疏水改性,制备了一种新型纳米KH550-C18/SiO₂复合粒子降黏剂。采用红外光谱（FT-IR）、热重分析（TG）、透射电镜（TEM）、扫描量热分析（DSC）等手段对改性后纳米SiO₂粒子的结构和性质进行分析表征。将其应用于大庆高蜡稠油进行降黏性能测试,研究了改性剂用量配比和降黏剂加入量对降黏效果的影响。结果表明,复合改性后,颗粒团聚程度减轻,在有机介质中能均匀稳定分散;纳米KH550-C18/SiO₂复合粒子表面由于接枝了含有极性基团的有机长链,能同时起到改善蜡质结晶行为和抑制胶质、沥青质形成大尺寸聚集体的作用;在最佳合成条件和最佳加入量时,该降黏剂在40℃的表观降黏率和净降黏率分别达66.91%和40.32%,优于市售EVA降黏剂。更多还原

【Abstract】 A novel nano-silica composite particle viscosity reducer for heavy oil was prepared by modifying the surface of nano-silica with silane couping agent KH550 and stearic acid.The structure and property of modified nano-silica particles were characterized and analyzed by FTIR,TG,TEM and DSC.Its viscosity reducing effect for high-wax heavy oil in Daqing oilfield was studied,and the effects on viscosity reducing were investigated by the ratio of modifier and dosage of viscosity reducer.After surface modification,the nano-silica composite particles were low agglomerated and could be dispersed in organic medium stably.Because the nano-sized KH550-C18/SiO₂ composite particles were surface grafted with organic long chain containing polar group,they could change wax’s crystallization behavior and prevent colloid and asphaltene forming large-sized aggregate.Under the optimal synthesis conditions and the best addition,its apparent viscosity reducing ratio and pure viscosity reducing ratio reached 66.91% and 40.32% respectively at 40 ℃,which is better than the commercial viscosity reducer EVA.更多还原