Porous analcime composite synthesized from solid waste: A cost-effective and superb adsorbent for efficient removal of Cu(II) and cationic dye

Abstract

The harmless transformation of solid waste into new materials capable of decontaminating wastewater is a "one stone, three birds" strategy to minimize the harm of waste and maximize resource utilization. Semi-coke (SC) is a kind of solid waste with abundant reserves, but it is hard for SC to be used as a scavenger of pollutants owing to its poor adsorption performance. In this paper, SC solid waste was transformed into cost-effective and high-efficiency silicate adsorbents with high specific surface area (333.52 m2/g; 16.04 times that of SC), excellent adsorption capacity for Cu(II) (71.74 mg/g; 5.13 times that of SC) and methylene blue (MB) (243.84 mg/g; 16.16 times that of SC) by an emerging upgraded reconstitution reaction route that is superior to conventional modification method. The calcined SC was converted to a porous analcite composite with improved pore structure, surface activity, and capturing ability to adsorbates. The analcite composite has high removal rate for Cu(II) (99.23%) and MB (99.99%) in solution with the starting concentration of 100 mg/L after being adsorbed by 1.5 g/L of the adsorbent. The porous adsorbent can be recycled for more than 5 times, and is potential to be applied for purifying dye or heavy metal-polluted water.