镉在黏土烧结过程中的固化机理

摘要/Abstract

摘要： 以黏土为原料,通过控制化学成分和烧结温度对Cd进行烧结固化,测试其对Cd的固化率和浸出浓度的影响,通过XRD、SEM、XPS、FTIR和重金属形态分析探讨黏土烧结过程中Cd的固化机理。结果表明:提高Fe₂O₃含量有利于赤铁矿的生成,Cd在750 ℃时的残渣态占比高于其他样品;提高铝硅比后,样品中CdAl₂Si₂O₈含量增多,当铝硅比为0.3、温度为1 050 ℃时,Cd的固化率最高可达99.64%;CaO含量提高至3%(质量分数)后,浸出浓度低于1 mg/L,钙长石的形成可提高浸出液的pH值进而抑制Cd的浸出。黏土经烧结后可形成更致密的结构,将Cd包裹在液相内,同时Cd²⁺可取代Ca²⁺进入晶体中生成稳定的CdAl₂Si₂O₈,使得Cd在黏土中被固定。

关键词: 镉, 黏土, 烧结, 重金属形态, 固化机理

Abstract: The effects of chemical composition and sintering temperature on the solidification rate and leaching concentration of Cd in clay sintering material were studied. And the solidification mechanism of Cd during clay sintering was investigated by XRD, SEM, XPS, FTIR and heavy metal speciation analysis. The results show that the increasing content of Fe₂O₃ is beneficial to the formation of hematite, and the residue proportion of Cd sintering at 750 ℃ is higher than that of other samples. The content of CdAl₂Si₂O₈ increases after increasing the Al/Si ratio. When the Al/Si ratio is 0.3 at the sintering temperature of 1 050 ℃, the solidification rate of Cd can reach 99.64%. When the CaO content increases to 3% (mass fraction), the leaching concentration is lower than 1 mg·L^-1. The formation of anorthite increases the pH value of the leaching solution and inhibits the leaching of Cd. The clay can form a denser structure after sintering, which can wrap Cd in the liquid phase. At the same time, Cd²⁺ can replace Ca²⁺ in the crystal to generate stable CdAl₂Si₂O₈, as a result, Cd is fixed in the sintered clay material.

Key words: cadmium, clay, sintering, heavy metal speciation, solidification mechanism

中图分类号:

X753

盛广宏, 王柯宜, 马研, 罗士宇, 王诗生, 刘玲. 镉在黏土烧结过程中的固化机理[J]. 硅酸盐通报, 2023, 42(6): 2047-2053.

SHENG Guanghong, WANG Keyi, MA Yan, LUO Shiyu, WANG Shisheng, LIU Ling. Solidification Mechanism of Cadmium in Clay Sintering[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2023, 42(6): 2047-2053.

参考文献

[1] 王光瑜, 杜永胜, 张红霞, 等. 共伴生多金属尾矿中重金属的高温固化研究进展[J]. 中国陶瓷, 2021, 57(9): 1-6+18.
WANG G Y, DU Y S, ZHANG H X, et al. Research progress on high temperature solidification of heavy metals in Co-associated polymetallic tailings[J]. China Ceramics, 2021, 57(9): 1-6+18 (in Chinese).
[2] 周伟伦, 廖正家, 陈涛, 等. 利用铁尾矿制备烧结砖的可行性及烧结固化机理[J]. 环境工程学报, 2021, 15(5): 1670-1678.
ZHOU W L, LIAO Z J, CHEN T, et al. Feasibility of using iron tailings to prepare sintering brick and sintering solidification mechanism[J]. Chinese Journal of Environmental Engineering, 2021, 15(5): 1670-1678 (in Chinese).
[3] 李洪达, 乐红志, 朱建平, 等. 赤泥烧结制品中的重金属溶出特性研究[J]. 硅酸盐通报, 2020, 39(9): 2932-2936+2943.
LI H D, LE H Z, ZHU J P, et al. Dissolution characteristics of heavy metals in red mud sintered products[J]. Bulletin of the Chinese Ceramic Society, 2020, 39(9): 2932-2936+2943 (in Chinese).
[4] WANG G W, NING X N, LU X W, et al. Effect of sintering temperature on mineral composition and heavy metals mobility in tailings bricks[J]. Waste Management, 2019, 93: 112-121.
[5] SU M H, LIAO C Z, CHEN D Y, et al. Evaluation of the effectiveness of Cd stabilization by a low-temperature sintering process with kaolinite/mullite addition[J]. Waste Management, 2019, 87: 814-824.
[6] 齐一谨, 徐中慧, 徐亚红, 等. 粉煤灰固化处理生活垃圾焚烧飞灰效果研究[J]. 环境科学与技术, 2017, 40(6): 98-103.
QI Y J, XU Z H, XU Y H, et al. The effect on immobilization of MSWI fly ash with coal fly ash[J]. Environmental Science & Technology, 2017, 40(6): 98-103 (in Chinese).
[7] ZOU J L, XU G R, LI G B. Ceramsite obtained from water and wastewater sludge and its characteristics affected by Fe₂O₃, CaO, and MgO[J]. Journal of Hazardous Materials, 2009, 165(1/2/3): 995-1001.
[8] 邱栋. 以河道底泥为基体的重金属稳定化机理研究[D]. 哈尔滨: 哈尔滨工业大学, 2020.
QIU D. Mechanisms of heavy metal immobilization in the matrix of river sediments[D]. Harbin: Harbin Institute of Technology, 2020 (in Chinese).
[9] 陈剑, 李碧雄, 梁鑫晓. 从化学成分探讨三种固废物掺入页岩烧结砖可行性[J]. 中国建材科技, 2017, 26(6): 69-70.
CHEN J, LI B X, LIANG X X. The feasibility of the fired brick incorporating three kinds of solid waste based on chemical components[J]. China Building Materials Science & Technology, 2017, 26(6): 69-70 (in Chinese).
[10] JUKIĆ M, ĆURKOVIĆ L, ŠABARIĆ J, et al. Fractionation of heavy metals in fly ash from wood biomass using the BCR sequential extraction procedure[J]. Bulletin of Environmental Contamination and Toxicology, 2017, 99: 524-529.
[11] 宋谋胜, 张杰, 李勇, 等. 电解锰渣合成堇青石陶瓷及其烧结性能研究[J]. 环境科学与技术, 2019, 42(8): 34-39.
SONG M S, ZHANG J, LI Y, et al. Synthesis and sintering properties of cordierite ceramic prepared by electrolytic Manganese residue[J]. Environmental Science & Technology, 2019, 42(8): 34-39 (in Chinese).
[12] 吴世明, 雷翅, 张鹏, 等. 烧结制度和氧化铁含量对轻质多孔陶粒相关性能的影响研究[J]. 新型建筑材料, 2018, 45(4): 9-12+123.
WU S M, LEI C, ZHNAG P, et al. Study on effect of sintering system and Fe₂O₃ conent on the properties of light porous ceramsite[J]. New Building Materials, 2018, 45(4): 9-12+123 (in Chinese).
[13] 谢茂林, 罗德礼, 鲜晓斌, 等. 氧化铝添加量对超高压烧结碳化硅性能的影响[J]. 硅酸盐学报, 2008, 36(8): 1144-1147.
XIE M L, LUO D L, XIAN X B, et al. Effect of alumina on the properties of ultra-high pressure sintered silicon carbide[J]. Journal of the Chinese Ceramic Society, 2008, 36(8): 1144-1147 (in Chinese).
[14] SU M H, TANG J F, LIAO C Z, et al. Cadmium stabilization via silicates formation: efficiency, reaction routes and leaching behavior of products[J]. Environmental Pollution, 2018, 239: 571-578.
[15] 田梦莹, 杨玉飞, 黄启飞, 等. pH值对烧结砖中重金属释放的影响[J]. 环境工程学报, 2014, 8(5): 2057-2062.
TIAN M Y, YANG Y F, HUANG Q F, et al. Effects of pH on release of heavy metal in sintered brick[J]. Chinese Journal of Environmental Engineering, 2014, 8(5): 2057-2062 (in Chinese).
[16] LI C, WEN Q J, HONG M Z, et al. Heavy metals leaching in bricks made from lead and zinc mine tailings with varied chemical components[J]. Construction and Building Materials, 2017, 134: 443-451.
[17] 李志川, 杨一博, 马蒸钊, 等. 利用生活垃圾焚烧飞灰制备全废物基微晶玻璃[J]. 环境工程学报, 2022, 16(6): 1925-1932.
LI Z C, YANG Y B, MA Z Z, et al. Preparation of entirely waste-based glass-ceramics from municipal solid waste incineration fly ash[J]. Chinese Journal of Environmental Engineering, 2022, 16(6): 1925-1932 (in Chinese).
[18] CHEN Y L, ZHANG Y M, CHEN T J, et al. Preparation and characterization of red porcelain tiles with hematite tailings[J]. Construction and Building Materials, 2013, 38: 1083-1088.
[19] 金彪, 赵亮, 汪潇, 等. 利用煤矸石、页岩、污泥制备烧结砖的研究[J]. 非金属矿, 2021, 44(5): 39-41.
JIN B, ZHAO L, WANG X, et al. Preparation of sintered brick with sludge, shale and gangue[J]. Non-Metallic Mines, 2021, 44(5): 39-41 (in Chinese).
[20] LIU T Y, XIE Y X, GUO X G, et al. The role and stabilization behavior of heavy metal ions in eco-friendly porous semi-vitrified ceramics for construction application[J]. Journal of Cleaner Production, 2021, 292: 125855.
[21] 武成利, 王蓓蓓, 陶然, 等. 用XPS研究高灰熔融温度煤灰的矿物结构转化[J]. 光谱学与光谱分析, 2018, 38(7): 2296-2301.
WU C L, WANG B B, TAO R, et al. Study of mineral structure transformation of coal ash with high ash melting temperature by XPS[J]. Spectroscopy and Spectral Analysis, 2018, 38(7): 2296-2301 (in Chinese).
[22] 罗忠涛, 刘垒, 康少杰, 等. 地聚合物固化/稳定有毒重金属及作用机理研究进展[J]. 材料导报, 2018, 32(11): 1834-1841.
LUO Z T, LIU L, KANG S J, et al. Research progress on immobilization/stabilization of toxic heavy metals by geopolymers[J]. Materials Review, 2018, 32(11): 1834-1841 (in Chinese).
[23] FERNÁNDEZ-JIMÉNEZ A, PALOMO A. Mid-infrared spectroscopic studies of alkali-activated fly ash structure[J]. Microporous and Mesoporous Materials, 2005, 86(1/2/3): 207-214.
[24] RAMOS G A, PELISSER F, PAUL GLEIZE P J, et al. Effect of porcelain tile polishing residue on geopolymer cement[J]. Journal of Cleaner Production, 2018, 191: 297-303.
[25] HIVREKAR M M, SABLE D B, SOLUNKE M B, et al. Network structure analysis of modifier CdO doped sodium borate glass using FTIR and Raman spectroscopy[J]. Journal of Non-Crystalline Solids, 2017, 474: 58-65.