Fabrication and Application of Low-Cost Thiol Functionalized Coal Fly Ash for Selective Adsorption of Heavy Toxic Metal Ions from Water

详细信息    查看全文

• 作者：Subhajit Dash ; Haribandhu Chaudhuri ; Radha Gupta ; Udayabhanu G. Nair ; Ashis Sarkar
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2017
• 出版时间：February 15, 2017
• 年：2017
• 卷：56
• 期：6
• 页码：1461-1470
• 全文大小：642K
• ISSN：1520-5045

文摘

A novel thiol modified coal fly ash (CFA-SH) is successfully synthesized by a facile, efficient, and environmentally friendly process using 3-mercaptopropyltrimethoxysilane (MPTS). Various techniques have been used to characterize thoroughly the structure, the surface property, and the presence of the mercaptopropyl groups. The synthesized material proves to be an effective and selective adsorbent for removal of Hg²⁺ and Cd²⁺ ions from aqueous solution. The effect of time, pH, sample dose, speed, temperature, and metal ion concentrations were investigated thoroughly to optimize the sorption process. The kinetics data fitted in accordance with the pseudo-second-order model. It is also noticed that the Langmuir equation provides an accurate description of these sorption data, implying that monolayer sorption took place during adsorption. The quick and excellent uptake capacities (q_m of 361.01 mg g^–1 for Hg²⁺ within 50 min at pH 8 and 106.38 mg g^–1 for Cd²⁺ within 60 min at pH 8) of the sorbent can be described on the basis of the hard and soft acid–base principle (HSAB) and electrostatic attraction. Moreover, both adsorbents and adsorbates can be reused using concentrated HCl. Finally, the low cost of the developed sorbent is also the prime point of interest in this experiment.