Solidification/Stabilization of Chromium in Red Mud-based Geopolymer  

作　　者：田崇霏 LUO Zhongtao LIU Lei LIU Xiaohai 张美香 陈萌 HAI Ran TIAN Chongfei;LUO Zhongtao;LIU Lei;LIU Xiaohai;ZHANG Meixiang;CHEN Meng;HAI Ran(School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China;Henan Renbang Technology Co.,Ltd.,Luoyang 471700,China;School of Water Conservancy and Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;School of Architectural and Civil Engineering,Zhongyuan University of Technology,Zhengzhou 450007,China)

机构地区：[1]School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China [2]Henan Renbang Technology Co.,Ltd.,Luoyang 471700,China [3]School of Water Conservancy and Civil Engineering,Zhengzhou University,Zhengzhou 450001,China [4]School of Architectural and Civil Engineering,Zhongyuan University of Technology,Zhengzhou 450007,China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2024年第4期819-830,共12页武汉理工大学学报（材料科学英文版）

基　　金：Funded by the National Natural Science Foundation of China(Nos.52074245,52374416 and 52202029);the China Postdoctoral Science Foundation(No.2022M721058)。

摘　　要：Up to 1.5wt%of Cr(Ⅲ)salts(CrCl_(3),and Cr_(2)O_(3))and Cr(Ⅵ)salts(Na_(2)CrO_(4),and CaCr_(2)O_(7))were incorporated into red mud-based geopolymers,respectively.The solidification/stabilization,compressive strength,and durability of the Cr-containing geopolymers were investigated.The experimental results indicate that the red mud-based geopolymer could effectively solidify/stabilize different types of Cr salts with solidification/stabilization rates of above 99.61%.Geopolymers are environmentally safe when the dosage of CaCr_(2)O_(7)is≤1.0wt%,or the dosage of CrCl_(3),Cr_(2)O_(3),and Na_(2)CrO_(4)is≤1.5wt%,respectively.The effects of Cr salts on the compressive strength varies with the type and content of Cr salts.The freeze-thaw cycle is more destructive to geopolymer properties than sulfate attack or acid rain erosion.The solidification/stabilization of Cr is mainly attributed to the following reasons:a)The chemical binding of Cr is related to the formation of Cr-containing hydrates(eg,magnesiochromite((Mg,Fe)(Cr,Al)_(2)O_(4)))and doping into N-A-S-H gel and C-A-S-H gel framework;b)The physical effect is related to the encapsulation by the hydration products(e g,N-A-S-H gel and C-A-S-H gel).This study provides a reference for the treatment of hazardous Cr-containing wastes by solid waste-based geopolymers.

关 键 词：CHROMIUM SOLIDIFICATION/STABILIZATION GEOPOLYMER red mud DURABILITY 

分 类 号：X705[环境科学与工程—环境工程] TQ317[化学工程—高聚物工业]