文献类型：期刊文献

英文题名：Electrostatic potential on anti-scalants modified CaCO3 (104) surface: A molecular simulation study

作者：Yuan, Pei-Qing[1]; Kong, Ning[2]; Cheng, Zhen-Min[1]; Semiat, Raphael[3]

机构：[1] State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, China; [2] Beijing Golden State Engineering Co., Ltd., Beijing, China; [3] Rabin Desalination Laboratory, Grand Water Research Institute, Department of Chemical Engineering, Haifa, 32000, Israel

年份：2009

卷号：238

期号：1-3

起止页码：246

外文期刊名：Desalination

收录：EI(收录号：20090511878049)

语种：英文

外文关键词：Molecular dynamics - Electrostatics - Density functional theory - Calcium carbonate - Desalination - Precipitation (chemical) - Molecular structure - Water filtration - Ethers

摘要：Molecular dynamics simulation and Density Functional Theory were used to investigate the adsorption of two kinds of anti-scalant, ethane diphosphonic acid (EDPA) and polyether polyamino methylene phosphonate (PAPEMP), on the calcite (104) surface in order to increase the level of understanding of the anti-scaling mechanism in membrane processes for water desalination. Calculation results show that the performance of an anti-scalant is mainly determined by the negative electrostatic potential presented on the anti-scalant modified scale surface. A negative electrostatic potential on the scale surface can prevent not only the agglomeration of scale nuclei in the concentrate but also the precipitation of scale nuclei on the membrane surface. Phosphonate groups in 1,1-EDPA are bifunctional since they simultaneously satisfy the requirements for the electrostatic potential distribution and for the adsorption stability on the scale surface. As concerns PAPEMP, the above requirements are fulfilled respectively by different functional groups, i.e. ether groups and phosphonate groups. To simplify the role of functional groups in the anti-scaling mechanism means that the performance of an anti-scalant can be optimized by the combination of specific functional groups; furthermore, these functional groups can also be adjusted with respect to different scale surfaces. ? 2008 Elsevier B.V. All rights reserved.