Efficient activation of peroxymonosulfate by iron-containing mesoporous silica catalysts derived from iron tailings for degradation of organic pollutants

Abstract

Solid waste and water pollution are global environmental problems that need to be urgently solved. Using industrial solid waste to treat organic pollutant wastewater might be a good strategy to solve two problems. Herein, iron tailings were used to prepare iron-containing mesoporous silica (MFS) materials under a one-step hydrothermal route. The as-prepared MFS showed excellent photocatalytic degradation efficiency and stability over a wide pH range for five typical organic pollutants. Further degradation test using tap water and Xiangjiang River water notably confirmed its practical application. Quenching and ESR experiments revealed radical (including sulfate (∙SO4−), hydroxide (·OH), and superoxide (·O2−) radicals) and non-radical (including single oxygen (1O2)) pathways worked together in the MFS/PMS/vis system. The cost estimation of the waste-derived MFS materials indicated that the raw material cost could be reduced by $129.8 per kilogram compared to the conventional method. This strategy not only provides a possible solution to iron tailings solid waste problem, but also develops a benign approach to the design and preparation of heterogeneous catalysts. The as-prepared materials have great potential in wastewater treatment, and follow the idea of treating waste with waste to achieve sustainable development.