Synthesis of a Novel Zeolite–Activated Carbon Composite Using Lithium–Silicon-Powder Waste for Ammonia-Nitrogen and Methylene Blue Removal
Ziyi Shui, Lu Yao, Xiaoqin Pu, Lin Yang, Wenju Jiang, Xia Jiang
Abstract
A novel zeolite–activated carbon (Ze–AC) with Brunauer–Emmett–Teller (BET) specific surface area of 660 m2/g has been prepared successfully as a low-cost adsorbent for NH4+-N and methylene blue (MB) removal. The present Ze–AC composite showed the NaY zeolite structure (characteristic of faujasite) bonded with amorphous carbon. The introduced AC facilitated the formation of oxygen-containing species around silicon, enhanced the interaction of silicon, oxygen, and carbon, and improved the porous structure of Ze–AC. All these phenomena led to the excellent adsorbability for NH4+-N and MB, and the adsorption capacities for MB and NH4+-N were 15.49 (94.05% of that of zeolite) and 498.61 mg/g (54.03% of that of AC), respectively. NH4+ was mainly adsorbed by the interaction between Si, double C═O bond groups (C═O and COOH), and NH4+, whereas MB was mainly adsorbed on the C═O and COOH sites on Ze–AC. Overall, the findings in this work indicate that the Ze–AC composite prepared from the industrial waste LSP is a valuable adsorbent for the removal of multiple contaminants from water.