In situ synthesis of zeolites by geopolymerization with NaOH/KOH mixed solution and their potential application for Cd(II) immobilization in paddy soil

被引：4

作者：

Wu, Di ^{[1
]}

Huang, Yi ^{[1
]}

Xiao, Guqing ^{[1
]}

Li, Xuan ^{[1
]}

Yao, Xia ^{[1
]}

Deng, Zixuan ^{[1
]}

Tan, Rui ^{[1
]}

机构：

[1] Hunan City Univ, Sch Mat & Chem Engn, Yiyang 413002, Peoples R China

来源：

CLAY MINERALS | 2021年 / 56卷 / 02期

关键词：

available potassium; Cd(II) immobilization; geopolymer; in situ zeolite synthesis; NaOH/KOH mixed alkaline solution; FLY-ASH; TEMPERATURE; CONVERSION; STRENGTH; CADMIUM; CLAY;

D O I：

10.1180/clm.2021.29

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Geopolymers can be transformed into zeolites under certain synthesis conditions. However, zeolite formation is not frequently reported in KOH-activated geopolymers. This study attempted to explore zeolite synthesis through geopolymerization for a curing time of 24 h using mixed NaOH/KOH alkaline solution as an activator, and then applying the geopolymer-supported zeolites to immobilize Cd(II) in paddy soil. The K2O/M2O-H2O/SiO2 and K2O/M2O-OH-/SiO2 binary zeolite crystallization phase diagrams were obtained. Zeolite A, faujasite and sodalite formed at lower K2O/M2O molar ratios (0-0.2), ferrierite formation was favoured at a K2O/M2O molar ratio of 0.2-0.4 and zeolite K-I and zeolite F-K (both K-zeolites) were observed at a K2O/M2O molar ratio of 0.6. The geopolymer-supported zeolites had micropores and mesopores and specific surface area values of 44.2-74.8 m(2) g(-1). The material displayed a considerable Cd(II) immobilization efficiency (55.6-58.7% at 4-6 wt.% addition of zeolite).

引用

页码：156 / 167

页数：12