Solubility product (Ksp)-controlled removal of chromate and phosphate by hydrocalumite

被引:70
作者
Qian, Guangren [1 ]
Feng, Linlin [1 ]
Zhou, Ji Zhi [1 ]
Xu, Yunfeng [1 ]
Liu, Jianyong [1 ]
Zhang, Jia [1 ]
Xu, Zhi Ping [2 ]
机构
[1] Shanghai Univ, Sch Environm & Chem Engn, Shanghai 200444, Peoples R China
[2] Univ Queensland, Australian Inst Bioengn & Nanotechnol, ARC Ctr Excellence Funct Nanomat, Brisbane, Qld 4072, Australia
基金
澳大利亚研究理事会;
关键词
Hydrocalumite; Dissolution-reprecipitation; Intercalation; Phosphate; Chromate; LAYERED DOUBLE HYDROXIDES; FRIEDELS SALT; ION-EXCHANGE; CHLORIDE; CR(VI); SURFACE; WATER; LDHS; CA; CR;
D O I
10.1016/j.cej.2011.11.074
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
It has been revealed that hydrocalumite (Ca2Al-Cl-LDH) removes Cr (VI) via anion-exchange while P via dissolution-reprecipitation. In current work, the intercalation of Cr (VI) was relative to the remaining LDH, which resulted in the increase of Cr (VI) removal amount with increasing pH. In contrast, more Ca-5(PO4)(3)OH was precipitated at initial pH 5.0 in the case of P removal, which was attributed to more hydrocalumite dissolved at such low pH. Moreover, the composition of the final solution in each case provided the evaluation of free ionic concentrations product (CP) which demonstrates that the formation of product was related to its CP value that was higher than or close to the corresponding Ksp. As Ca-5(PO4)(3)OH or LDH-CrO4 has the lowest solubility product (Ksp) among all possible solid in each case, our results propose that the removal process of chromate and phosphate over hydrocalumite was controlled by Ksp of the product. (C) 2011 Elsevier B.V. All rights reserved.
引用
收藏
页码:251 / 258
页数:8
相关论文
共 36 条
[1]  
[Anonymous], 1992, STAND METH EX WAT WA
[2]  
[Anonymous], LAYERED DOUBLE HYDRO
[3]   Ion exchange of different phosphate ions into the zinc-aluminium-chloride layered double hydroxide [J].
Badreddine, M ;
Legrouri, A ;
Barroug, A ;
De Roy, A ;
Besse, JP .
MATERIALS LETTERS, 1999, 38 (06) :391-395
[4]   Friedel's salt, Ca2Al(OH)6(Cl,OH)•2H2O:: Its solid solutions and their role in chloride binding [J].
Birnin-Yauri, UA ;
Glasser, FP .
CEMENT AND CONCRETE RESEARCH, 1998, 28 (12) :1713-1723
[5]   PhreeqC modeling of Friedel's salt equilibria at 23±1 °C [J].
Bothe, JV ;
Brown, PW .
CEMENT AND CONCRETE RESEARCH, 2004, 34 (06) :1057-1063
[6]  
Braterman P.S., 2004, Handbook of layered materials, Ed, P373
[7]   Chemical changes in concrete due to the ingress of aggressive species [J].
Brown, PW ;
Doerr, A .
CEMENT AND CONCRETE RESEARCH, 2000, 30 (03) :411-418
[8]   A comparative study between chloride and calcined carbonate hydrotalcites as adsorbents for Cr(VI) [J].
Carriazo, D. ;
del Arco, M. ;
Martin, C. ;
Rives, V. .
APPLIED CLAY SCIENCE, 2007, 37 (3-4) :231-239
[9]   HYDROTALCITE-TYPE ANIONIC CLAYS: PREPARATION, PROPERTIES AND APPLICATIONS [J].
Cavani, F. ;
Trifiro, F. ;
Vaccari, A. .
CATALYSIS TODAY, 1991, 11 (02) :173-301
[10]   Synthesis of a novel layered double hydroxides [MgAl4(OH)12](Cl)2•2.4H2O and its anion-exchange properties [J].
Chitrakar, Ramesh ;
Makita, Yoji ;
Sonoda, Akinari ;
Hirotsu, Takahiro .
JOURNAL OF HAZARDOUS MATERIALS, 2011, 185 (2-3) :1435-1439