Page 154 - 精细化工2019年第12期
P. 154
第 36 卷第 12 期 精 细 化 工 Vol.36, No.12
2019 年 12 月 FINE CHEMICALS Dec. 2019
水处理技术与环境保护
钛柱撑蒙脱石对镍离子和锰离子的吸附机理
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宋 祥 ,庹必阳 1,2,3* ,赵徐霞 ,向海春
(1. 贵州大学 矿业学院,贵州 贵阳 550025;2. 贵州省非金属矿产资源综合利用重点实验室,贵州 贵
阳 550025;3. 喀斯特地区优势矿产资源高效利用国家地方联合工程实验室,贵州 贵阳 550025)
摘要:以钠基蒙脱石(Na-MMT)、钛酸四丁酯作基质材料,通过溶胶-凝胶法制备了钛柱撑蒙脱石(Ti-MMT)。
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利用 XRD、FTIR 及 SEM 对 Ti-MMT 进行了结构表征,考察了不同吸附条件对 Ti-MMT 吸附 Ni 和 Mn 的影
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响,并重点分析水溶液 pH 对 Ti-MMT Zeta 电位及吸附的影响,探究了 Ti-MMT 吸附 Ni 和 Mn 的机理。结果
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表明:Ti-MMT 具有较大的晶面间距(d 001 =2.94 nm);pH 对吸附 Ni 与 Mn 有较大影响,去除率随初始水溶液
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pH 增加而提高。在 pH=7,Ni 和 Mn 初始质量浓度为 50 mg/L,Ti-MMT 投加量分别为 5 和 9 g/L 时,Ni 在
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318 K 下吸附 120 min,吸附量可达 9.46 mg/g,去除率可达 94.59%,Mn 在 328 K 下吸附 180 min,吸附量可
达 4.82 mg/g,去除率可达 86.73%。此外,Ti-MMT 对两种离子的吸附都更符合 Temkin 等温吸附模型及拟二级
动力学模型,吸附过程受液膜扩散、颗粒内扩散等环节控制,且以离子交换的化学吸附为主。热力学分析表明,
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Ti-MMT 对 Ni 的吸附属于自发吸热熵增过程,而 Mn 属于吸热熵增的非自发过程。
关键词:钛柱撑蒙脱石;吸附;二价镍离子;二价锰离子;水处理技术
中图分类号:X703.5 文献标识码:A 文章编号:1003-5214 (2019) 12-2482-09
Adsorption Mechanism of Titanium Pillared Montmorillonite for
Nickel and Manganese Ions
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SONG Xiang , TUO Bi-yang 1,2,3* , ZHAO Xu-xia , XIANG Hai-chun
(1. Mining College of Guizhou University, Guiyang 550025, Guizhou, China; 2. Guizhou Key Laboratory of
Comprehensive Utilization of Non-metallic Mineral Resources, Guiyang 550025, Guizhou, China; 3. National & Local
Joint Laboratory of Engineering for Effective Utilization of Regional Mineral Resources from Karst Areas, Guiyang
550025, Guizhou, China)
Abstract: Titanium pillared montmorillonite (Ti-MMT) was prepared by sol-gel method using sodium
montmorillonite (Na-MMT) and tetrabutyl titanate as matrix materials. The Ti-MMT were characterized by
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XRD, FTIR and SEM. Then, the effects of different adsorption conditions on the adsorption of Ni and
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Mn on Ti-MMT were investigated, and the effect of pH on Zeta potential and adsorption was emphatically
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analyzed. The mechanism of Ti-MMT adsorption of Ni and Mn was investigated. The results show that
Ti-MMT has a large interplanar spacing (d 001=2.94 nm); pH has a great influence on adsorption, and the
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removal rate of Ni and Mn increases with the increase of initial pH. At pH=7, the dosage of Ti-MMT is
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5 g/L, the initial mass concentration of Ni is 50 mg/L, and the adsorption time is 120 min at 318 K, Ni
adsorption capacity can reach 9.46 mg/g, and the removal rate can reach 94.59%. At pH=7, the dosage of
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Ti-MMT is 9 g/L, the initial mass concentration of Mn is 50 mg/L, and the adsorption time is 180 min at
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318 K, Mn adsorption capacity can reach 4.82 mg/g, and the removal rate can reach 86.73%. In addition,
Ti-MMT adsorption of both ions is more consistent with Temkin isotherm adsorption, and the pseudo-
second-order kinetics model. The adsorption process is controlled by liquid membrane diffusion and
intra-particle diffusion, and ion exchange chemisorption is dominant. Thermodynamic analysis shows that
收稿日期:2019-04-18; 定用日期:2019-06-14; DOI: 10.13550/j.jxhg.20190333
基金项目:国家自然科学基金(51464007);贵州省科技厅联合资金项目(黔科合 LH 字[2015]7684);博士基金〔贵大人基合字(2013)
51 号〕
作者简介:宋 祥(1996—),男,硕士生,E-mail:1697181013@qq.com。联系人:庹必阳(1979—),男,博士,教授,E-mail:
yntby@163.com。