原油油溶性降凝剂BS的合成及评价

Synthesis and evaluation of the oil-soluble pour-point depressant BS for crude oil

以甲基丙烯酸、十八醇、苯甲醇为原料,采用先酯化后聚合的方法合成了甲基丙烯酸十八酯-甲基丙烯酸苄酯聚合物降凝剂(BS),并对其进行了红外表征及GPC分子量分析。通过降凝效果评价,确定了聚合物BS的最佳合成条件:n(甲基丙烯酸十八酯)∶n(甲基丙烯酸苄酯)=15∶1,引发剂用量为单体总质量的0.7%,反应温度65℃,反应时间6h。最佳条件下合成的降凝剂在10%的含蜡模拟油中的最佳加量为0.4%(占模拟油的质量分数),降凝幅度为4.5℃;当0.4%降凝剂加入到5%的含蜡模拟油中降凝幅度为9.5℃,并考察了其对多种原油的降凝效果,发现降凝剂对不同含蜡原油都有一定的降凝效果,胶质和沥青质含量较高的原油效果较好,其降凝幅度最高可达11.5℃。

A new pour point depressant BS of stearyl methacrylate-benzyl methacrylate bipolymer,was synthesized from methyl acrylate,octadecanol and benzyl alcohol through esterification and polymerization reactions. The chemical structure of the copolymer was identified by infrared spectral analysis（IR） and gel permeation chromatograghy analysis（GPC）. The optimum reaction conditions based on the performance of pour-point depressant were ： the monomer molar ratio of stearyl methacrylate and benzyl methacrylate was 15∶1,with the initiator dosage of 0.7%,polymerization temperature of 65℃ and the reaction time was 6h. When the dosage of pour-point depressants was 0.4%（mass fraction in the model oil）,the pour point decreased by 4.5℃ and 9.5℃ for the model oils with 10% and 5% wax,respectively. The synthesized pour-point depressant was effective for diverse crude oils with different wax contents, especially for those with higher content of resins and asphaltenes,and a maximum pour point decrease of 11.5℃ could be obtained.