Stabilization of Chromium(VI) from Chromic Slag with Two Types of Thiol Collectors

Abstract:

Two thiol collectors, sodium diethyldithiocarbamate (DDTC) and potassium ethyl xanthate (EXT), were adopted to stabilize hexavalent chromium from chromic slag. The average usage of each thiol collector is 62.5 μmol∙g^-1 in chromic slag. The leaching characteristic of Cr⁶⁺ in chromic slag was analyzed according to the acidic extraction process with the toxicity characteristic leaching procedure (TCLP) and the procedures of extraction in water with the horizontal vibration method (HMV). Under the 0.1 mol∙L^-1 TCLP and HMV conditions, we compared them with FeSO₄ and found that two thiol collectors presented better stabilization effects for Chromium (VI) from chromic slag, especially the effect by DDTC is more stabilized than that by EXT. The rate of their stabilized treatments is 78.42% and 83.18%, respectively, which both are obviously higher than that by FeSO₄. Heavy metal-thiol collectors such as flocculent mass is more stabilized under the neutral and alkalized conditions (pH>8), but it may be partly dissolved under the acidic conditions (pH<6) and the leaching amount of Cr⁶⁺ from chromic slag will increase quickly with pH decreasing.

• Periodical: Advanced Materials Research (Volume 414)
• Pages: 186-190
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.414.186
• Online since: December 2011
• Authors: Qing Ping Lu, Chang Sheng Jiang, Qing Ju Hao
• Keywords: Chelator, Chromic Slag, Stabilization

References

[1] Liyuan Chai, Kun Zhao, Yude Shu, Wenjie Zhu, Kinetics of chromium-containing slag leached by NaCl, J. Cent. South Univ. (Science and Technology). 38(2007) 445-446.

[2] Min Zheng, Xianrong Li, Yanyan Meng, Recovery of chromium from chromium slag by chloridizing roasting process, J. Environmental protection of chemical industry. 30(2010) 242-243.

[3] Environmental science voluminous dictionary editorial Committee. Environmental science voluminous dictionary, BeiJing, (1991).

[4] Yankui Tang, Kelu Wei, Zhangfa Tong, Adsorption of Cr(VI) from water on zirconium-aluminum pillared bentonite modified by microwave radiation, J. Environmental protection of chemical industry. 31(2011) 1-3.

[5] Huisheng Shi, Lili Kan, Study on the properties of chromium residue-cement matrices (CRCM) and the influences of superplasticizers on chromium(VI)-immobilising capability of cement matrices, J. Hazard Mater. 162(2009) 913-919.

DOI: 10.1016/j.jhazmat.2008.05.117

[6] Haisong Hao, Yi Xie, Lin Yang, Treatment technology and multipurpose use of hazardous wastes, J. Safety and Environmental Engineering. 16( 2009) 36-37.

[7] Ruina Zhang, Youcai Zhao, Shi Xu, An overview on treatment of municipal solid waste incineration fly ash, J. University of Science and Technology of Suzhou (Engineering and Technoloy). 16 (2003) 22-24.

[8] Ke Xu, Li Wu, Dezhen Chen, Stabilization of heavy metals in incineration fly ash with chelating agents, J. Energy Research and Information. 21 (2005) 83-84.

[9] G.R. Qian, H.H. Zhang, X.L. Zhang, et al., Modification of MSW fly ash by anionic chelating surfactant, J. Journal of Hazardous Materials. 121 (2005) 251-258.

DOI: 10.1016/j.jhazmat.2005.02.012

[10] Qisheng Ren, Xinrong Song, Jianqing Li, et al., One kind of heavy metal chelating chitosan derivatives containing composition. China. Patent 03, 178, 585. (2004).

[11] H. Toshio, Stabilization treatment method for heavymethod in fly ash. Japan. patent 2, 004, 202, 407. (2004).

[12] EPA Test Method 1311-1, Toxicity Characteristic Leaching Procedure[S].

[13] GB 5086. 2-1997, EPA Test Method 1311-1, Toxicity Characteristic Leaching Procedure[S].

[14] Code of Federal Regulations [S]. US EPA, vol. 40, Part 261, 24 (1992).

[15] GB 5085. 3-1996, EPA Test Method 1311-1, Toxicity Characteristic Leaching Procedure[S].

[16] Haijun Zhang, Ying Yu, Yuwen Ni. Stabilization of heavy metals in municipal solid waste incineration fly ash with the thiol collectors, J. Enviromental Science. 28 (2007) 1900-(1902).