绿色环保型聚天冬氨酸阻垢剂合成与阻垢性能

Synthesis of the environmental scale inhibitor,polyaspartic acid,and its scale inhibition capacity

以马来酸酐(MA)与氨水为原料热缩聚法合成聚天冬氨酸阻垢剂,分别考察了原料配比、热缩聚温度和热缩聚时间对产物的阻垢性能的影响,得到最佳合成条件:n(MA)∶n(NH3)为1∶2.0,热缩聚温度240℃,热缩聚时间3 h。当实验水中Ca2+质量浓度为240 mg/L时,聚天冬氨酸阻垢剂的阻垢率达到72%,适用于低矿化度的工业循环冷却水和油田回注水。同时使用L-天冬氨酸对聚合物开环改性,其阻垢率可达到87%。

Using maleic anhydride and ammonium hydroxide as raw materials,polyaspartic acid has been synthesized by means of pyrocondensation polymerization. The effect of some reaction conditions,such as temperature, time, molar ratio of maleie anhydride and ammonia on scale-inhibiting capacity are investigated. The optimal conditions for synthesis are as follows ： the molar ratio of maleic anhydride and ammonia is 1 ： 2.0, reaction time 3 h at 240 °C. The scale inhibiting rate is 72% when the mass concentration of Ca2＋ in experimental water is 240 mg/L. It could be used as scale inhibitor in low mineralized circulating cooling water and oil-field reinjection water especially. In addition, L-aspartic acid has been used for modifying the polymer,in order to enhance the inhibiting efficiency. Its inhibition rate can reach 87%.