Solidification/stabilization of chromite ore processing residue using alkali-activated composite cementitious materials.
Chromite Ore Processing Residue (COPR) produced in chromium salt production process causes a great health and environmental risk with Cr(VI) leaching. The solidification/stabilization (S/S) of COPR using alkali-activated blast furnace slag (BFS) and fly ash (FA) based cementitious material was investigated in this study. The optimum percentage of BFS and FA for preparing the alkali-activated BFS-FA binder had been studied. COPR was used to replace the amount of BFS-FA or ordinary Portland cement (OPC) for the preparation of the cementitious materials, respectively. The immobilization effect of the alkali-activated BFS-FA binder on COPR was much better than that of OPC based cementitious material. The potential for reusing the final treatment product as a readily available construction material was evaluated. X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR) and scanning electron microscope with energy dispersive spectrometer (SEM-EDS) analysis indicated that COPR had been effectively immobilized. The solidification mechanism is the combined effect of reduction, ion exchange, precipitation, adsorption and physical fixation in the alkali-activated composite cementitious material.
State Key Laboratory for Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China.
Xiao
X
Huang
Dept. of Construction Management, Chung Hua University, No. 707, Wufu Rd., Sec. 2, Hsinchu, 30012, Taiwan.
RanLiang
R
Zhuang
State Key Laboratory for Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China.
Faheem
F
Muhammad
State Key Laboratory for Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China.
Lin
L
Yu
Dept. of Construction Management, Chung Hua University, No. 707, Wufu Rd., Sec. 2, Hsinchu, 30012, Taiwan. Electronic address: ycshiau@chu.edu.tw.
YanChyuan
Y
Shiau
State Key Laboratory for Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China. Electronic address: litonwei@cqu.edu.cn.
Dongwei
D
Li
D000468:Alkalies / Q000737:chemistry*; D002857:Chromium / Q000737:chemistry* / Q000633:toxicity; D060729:Coal Ash / Q000737:chemistry; D003252:Construction Materials; D004350:Drug Residues / Q000737:chemistry*; D004355:Drug Stability; D007220:Industrial Waste / Q000009:adverse effects; D007474:Ion Exchange; D008855:Microscopy, Electron, Scanning; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
D000468:Alkalies; D060729:Coal Ash; D007220:Industrial Waste; D002857:Chromium
Alkali-activated; Blast furnace slag; Chromite ore processing residue; Fly ash; Solidification/stabilization