Abstract In this study, the appropriate nano-porous magnesium aluminate spinel was synthesized by self-combustion route, explored for the photocatalytic removal of methylene blue remained in the wastewater. The effects of gel preparation pH and calcination temperature on the spinel structural characteristics and solar photocatalytic activity were investigated by response surface method. The maximum removal efficiency was achieved by the gel preparation in the acidic environment, pH: 2, followed by calcination at 700 °C. The flame-type combustion showed the key role in the advancement of photoactivity due to nitrogen doping in the structure of partially crystalline spinel. The produced composite displayed a nano-porous structure with average pore diameter of 5 nm. Approximately, 90% of contaminant was removed in 40 min under the solar irradiation. The removal rate seems to be dependent of initial dye concentration,

中文翻译：

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铝酸镁在阳光照射下处理亚甲蓝污染废水的光活性：自燃因素对尖晶石特性的影响

摘要 本研究通过自燃路线合成了合适的纳米多孔铝酸镁尖晶石，探索了光催化去除废水中残留的亚甲基蓝。采用响应面法研究了凝胶制备pH和煅烧温度对尖晶石结构特性和太阳能光催化活性的影响。通过在酸性环境中制备凝胶，pH：2，然后在 700°C 下煅烧，实现了最大的去除效率。由于氮掺杂在部分结晶尖晶石的结构中，火焰型燃烧显示出提高光活性的关键作用。生产的复合材料显示出平均孔径为 5 nm 的纳米多孔结构。在太阳照射下，大约 90% 的污染物在 40 分钟内被去除。