低初黏凝胶体系中多元酸铬交联剂的合成

SYNTHESIS OF CHROMIUM POLYBASIC ACID CROSSLINKER IN LOW INITIAL VISCOSITY GEL SYSTEM

为改善聚合物驱油后低效无效循环严重的问题,通过正交实验,以乳酸、醋酸、顺丁烯二酸为三氯化铬的多元络合剂,乙二醇及抗坏血酸钠为原料,合成并筛选出初始黏度低、成胶时间可控的多元酸铬交联剂。实验结果表明:多元酸铬交联剂最优合成条件为反应时间6 h,合成温度70℃,三元酸与三氯化铬投料质量比2∶1,pH=4~5。在清水中成胶后凝胶体系初始黏度为19.96 mPa·s,延缓时间0~30 d可控,最终成胶黏度在2 800 mPa·s以上。

In order to improve the serious problem of inefficient and ineffective circulation after polymer flooding,an orthogonal synthesis experiment was conducted,using lactic acid,acetic acid,and maleic acid as multicomponent chelating agents for chromium trichloride,ethylene glycol,and sodium ascorbate as raw materials,to synthesize and screen out multicomponent chromium cross-linking agents with low initial viscosity and controllable gelation time.The experimental results show that the optimal synthesis conditions for the polybasic acid chromium crosslinking agent are reaction time of 6 hours,synthesis temperature of 70℃,mass ratio of ternary acid to chromium trichloride 2∶1,and synthesis pH value of 45.After gelation in clear water,the initial viscosity of gel system is 19.96 mPa·s,and the delay time is controllable from 0 to 30 days.The final gelation viscosity is more than 2800 mPa·s.