Mechanical activation of natural chalcopyrite for improving heterogeneous Fenton degradation of tetracycline

机械活化天然黄铜矿强化非均相Fenton催化降解废水中四环素

Natural minerals receive growing attention as inexpensive, green, and efficient catalysts for degradation of organic pollutants. Mechanical activation of natural chalcopyrite was conducted for improving the catalytic performance.Tetracycline degradation was evaluated in the presence of hydrogen peroxide and mechanically activated chalcopyrite.Tetracycline degradation at 100 min is 55.52%(Chp10), 68.97%(Chp30), 77.79%(Chp60), and 86.43%(Chp120),respectively, and the rate constant of pseudo-first-order kinetics is 0.0079, 0.0109, 0.0137 and 0.0192 min^(-1), respectively.Chalcopyrite samples were examined by multiple characterizations. Mechanical activation of natural chalcopyrite induces the decline of particle size and slight increase of surface area, smaller grain size, lattice strain, and partial sulfur oxidation. The relationship between catalytic activity and property change manifests that the improved catalytic ability is mainly ascribed to the increase of surface area and surface oxidation induced by mechanical activation. This work provides novel insights into the improvement of catalytic performance of natural minerals by mechanical activation.

废水中有机污染物是环境领域亟待解决的难题之一,非均相高级氧化工艺是降解有机污染物的高效方法,然而,非均相高级氧化工艺受限于高效催化剂的开发。天然矿物具有廉价、资源丰富、环境友好等优点,用于非均相Fenton催化降解废水中有机污染物受到越来越多的关注。天然矿物的催化活性较低、如何提高天然矿物的催化活性是亟待解决的问题。本文提出机械活化提高天然黄铜矿的催化性能,通过非均相Fenton降解四环素评估催化活性变化。球磨10、30、60和120 min的天然黄铜矿对四环素的降解率分别为55.52%、68.97%、77.79%和86.43%,反应速率常数分别为0.0079、0.0109、0.0137和0.0192 min^(-1),表明机械活化能显著提高天然黄铜矿的催化性能。通过表征分析发现,机械活化使黄铜矿的颗粒减小、比表面积增加、晶格尺寸减小、晶格畸变以及表面硫氧化。通过分析催化活性与黄铜矿不同参数的线性关系表明,催化活性提高主要归因于机械活化造成的比表面积增加与表面氧化。本研究表明机械活化能够提高天然矿物的催化活性,为开发天然矿物基高效非均相Fenton催化剂提供新的见解。