不同链长有机膦酸阻垢剂对硫酸钡结晶过程的影响

考察了二亚乙基三胺五亚甲基膦酸(DETPMP)和二亚己基三胺五亚甲基膦酸(BHMTPMP)阻垢剂对BaSO₄结晶的影响。利用Zeta电位分析了2种阻垢剂对BaSO₄晶体表面电荷的影响,运用经典的均相成核理论解释了阻垢剂的抑制机理,利用扫描电子显微镜表征了硫酸钡晶体的形貌。结果表明,在实验浓度范围内,2种有机膦酸阻垢剂通过提高BaSO₄晶体析出时的表面自由能和结晶活化能抑制了BaSO₄结晶,BHMTPMP的抑制效果更明显;2种阻垢剂使BaSO₄晶体表面Zeta电位绝对值升高,pH=8时Zeta电位绝对值达到最大;2种阻垢剂使BaSO₄晶体形貌发生显著变化,晶体表面出现明显台阶状生长特征。

Effect of Phosphate Inhibitors With Various Chain Length on the Formation of BaSO4 Crystal

 The effects of diethylene triamine penta (methylene phosphonic acid) (DETPMP) and bis(hexamethylene triamine penta (methylene phosphonic acid)) ( BHMTPMP) on formation of BaSO₄ crystal were studied. The surface structure and performance of BaSO₄ crystal were characterized by Zeta potential analysis. The inhibitory mechanism was discussed according to the homogeneous nucleation theory. The morphology of BaSO₄ crystal was characterized by means of SEM. It was found that the effect of the phosphonate inhibitors on the formation of BaSO₄ crystal may be from the increase of surface free energy and activation energy of BaSO₄ crystalline. The inhibition effect of BHMTPMP was better than that of DETPMP. When the inhibitors were added during precipitation of BaSO₄, the absolute Zeta potential value of BaSO₄ crystal increased and reached its maximum value at pH=8 of the solution. The regular shapes of BaSO₄ crystals were changed obviously in the presence of the phosphonate inhibitors. The step growth characteristics presented significantly on the surface of BaSO₄ crystal.