Efficient elimination behavior and mechanism of heavy metal by eco-friendly potassium titanium trisilicate. Issue 1 (February 2021)

• Record Type: Journal Article
• Authors: Chen, Mingyue; Nong, Shuying; Riaz, Muhammad Sohail; Hu, Keyan; Xiao, Yi; Huang, Fuqiang
• Is Part Of: Journal of environmental chemical engineering. Volume 9:Issue 1(2021)
• Publication Date: 2021-02
• Subjects: Frame structure -- Chemical stability -- Heavy metal -- High efficiency -- Drinking level; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2020.104823
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: Frame structural material holds great potential for adsorption but challenging for stable in harsh aqueous medium. Herein, a framework potassium titanium silicate K2 TiSi3 O9 H2 O with wide acid durability is used for heavy metal purification and shows excellent performance. The adsorption capacity of K2 TiSi3 O9 H2 O reaches maximum 221 and 123 mg/g towards Pb 2+ and Cd 2+ at room temperature. The residual Pb 2+ concentration holds at 0.0006 mg/L that is far below the limits in drinking water, and the removal efficiency of Pb 2+ (10–200 mg/L) still remains 60–73% even at strong acid solution. The readily exchanging K sites in K2 TiSi3 O9 H2 O framework and abundant deprotonated hydroxyl groups afford the rapid adsorption rate and large uptake capacity. A large separation factor (10 2 –10 3 ) between competitive Na/Ca and heavy metal ions demonstrates this good selectivity. The removal rate of K2 TiSi3 O9 H2 O maintains 85% even after five cycles, indicating its good reproducibility. K2 TiSi3 O9 H2 O is also extendable to cationic dye removal with a capacity of 45.6 mg/g. This work provides this kind of framework titanium silicates with great structural and crystal stability for the high-efficient and massive elimination of heavy metals. Graphical Abstract: ga1 Highlights: The K2 TiSi3 O9 H2 O is developed for heavy metal removal to drinkable level. The sufficient mechanical strength and wide acid durability of K2 TiSi3 O9 H2 O. The absorption capacities for Pb, Cd and cationic MB are 221, 123 and 45 mg/g. Adsorption involves both ion exchange reaction and electrostatic interaction. Easy preparation and stable recycling performance let it for practical application.