有机膦与聚合物抑制剂对氟硅酸钠(钾)结垢性能的协同抑制作用

Synergistic Effects of Organic Phosphorous and Polymer Additives on Sodium (Potassium) Fluosilicate Inhibition

采用浊度法和静态抑垢法,研究了抑制剂2-膦酸基-1,2,4-三羧酸丁烷(PBTCA)与水解聚马来酸酐(HPMA)对氟硅酸钠(钾)结晶的影响。运用经典结晶成核理论解释了抑制机理,利用扫描电子显微镜和X射线衍射技术表征了氟硅酸钠(钾)的晶体形貌和晶型。结果表明,PBTCA与HPMA通过提高氟硅酸钠(钾)结晶时的表面自由能而抑制氟硅酸钠(钾)的析出。PBTCA与HPMA之间存在明显的协同作用,PBTCA与HPMA共同作用使Na2SiF6的结晶表面自由能从108 mJ/m2升高至126 mJ/m2,溶液中Na+的阻垢率从6.2%上升至70.3%;使K2SiF6的结晶表面自由能从199 mJ/m2升高至230 mJ/m2,溶液中K+的阻垢率从10.2%升高至45.3%。PBTCA与HPMA的加入使氟硅酸钠(钾)的粒径变小,颗粒分散;空白溶液中晶体主要为NaKSiF6,PBTCA与HPMA混合体系中结晶产物主要为Na2SiF6和K2SiF6。

Effects of 2-phosphonobutane-1,2,4-tricarboxylic acid （PBTCA） and N-（2-hydroxypropyl）methacrylamide （HPMA） inhibitors on the sodium （potassium） fluorosilicate crystallization were studied by turbidity and static methods.Mechanism of inhibition was explained according to classic nucleation theory.Morphology and crystal form of sodium （potassium） fluorosilicate were characterized by SEM and XRD.The results show that PBTCA and HPMA can inhibit crystallization precipitation by improving the surface free energy of sodium （potassium） fluorosilicate.The mixture of PBTCA and HPMA has distinct synergy,which can improve surface free energy of Na2SiF6 from 108 mJ/m^2 to 126 mJ/m^2,inhibition rate of Na ＋ from 6.2% to 70.3%,surface free energy of K2SiF6 from 199 mJ/m^2 to 230 mJ/m^2 and inhibition rate of K^＋ from 10.2% to 45.3%,respectively.Particles of sodium（potassium） fluorosilicate are dispersed and diminished in the presence of PBTCA and HPMA.The crystal form is mainly NaKSiF6 in the blank solution,while they are mainly Na2SiF6 and K2SiF6 in the presence of PBTCA and HPMA.