Inorganic Chemicals Industry ›› 2021, Vol. 53 ›› Issue (8): 31-35.doi: 10.19964/j.issn.1006-4990.2020-0525

• Research & Development • Previous Articles     Next Articles

Molecular dynamics study on inhibition of calcite stepped surfaces growth by organic phosphonates

Chen Chunyu(),Men Lijuan,Ju Dianchun,Guo Lei,Yao Fusheng,Zhang Qi,Yu Hongyu   

  1. School of Metallurgical and Materials Engineering,Jiangsu University of Science and Technology,Zhangjiagang 215600,China
  • Received:2020-10-18 Online:2021-08-10 Published:2021-08-11

Abstract:

Organic phosphonic compounds are commonly used scale inhibitors in industrial cooling water system.Studying on the scale inhibition performance and mechanism of organic phosphonic acid scale inhibitors can provide reasonable theoreti-cal basis for the development and application of new scale inhibitors.The interaction mechanism between five organic phos-phine scale inhibitors and four steps of calcite in the process of industrial cooling water circulation was simulated by using the molecular dynamics (MD)method based on the PBC theoretical model.The results showed that the binding energy of organic phosphonic acid molecule and calcite(104) was minus,the process of interaction was exothermic reaction,and the scale in-hibitor molecule had well repressive effect on the growth of calcite(104).Through calculating combining capacity,it could be obtained that the adsorption capacity of the scale inhibitor molecule from strong to weak was as fouows HDTMP,EDTMP,ATMP,NDP and AMP.It was observed that the organic phosphonic acid molecules were mainly adsorbed on the active growth point of the crystallo graphic plane that the position of the terminal corner of the stepped plane and the position of the stepped inflection point so that the active position of crystallization plane was occupied and the further growth of the crystal plane was restrained.Based on the binding energy data of organic phosphonic acid and step surface,the adsorption capacity of the four terminal step surfaces from strong to weak was as follows CO3-CO3,CO3-Ca,Ca-CO3,Ca-Ca,so the stability was stronger,the adsorption capacity was weaker.

Key words: organic phosphonate inhibitor, calcite, stepped surface, molecular dynamic

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