The ferrite process can not only purify wastewater containing heavy metal ions but also recycle valuable metals from wastewater. Therefore, it is considered a promising technology to treat chromium-containing wastewater. However, the process has not been extensively applied in industry due to its high synthesis temperature. In this paper, the feasibility of chromite synthesis at room temperature was comprehensively studied. The effects of critical factors on the effluent quality and the crystallization behavior and stability of the synthetic products were investigated. Results showed that the removal ratio of chromium from wastewater was over 99.0%, and the chromium concentration in the supernatant reached the sewage discharge standard after undergoing the ferrite process at room temperature. Increases in the aeration rate, stirring rate, and reaction time were favorable for the formation of stable chromite. The particles obtained by the ferrite process at room temperature were characterized by a compact structure, and the maximum size of the particles reached 52 μm. Chromium gradually entered the spinel crystal structure during the synthesis process, and the molecular formula of the synthetic chromite might be Fe_3−xCr_xO₄, in which x was approximately 0.30. The path of the microscopic reaction was proposed to illuminate the synthesis mechanism of chromite under room temperature conditions. The present study has laid the foundation for the industrial application of the ferrite process in the purification and utilization of chromium-containing wastewater.

铁氧体工艺不仅可以净化含有重金属离子的废水，还可以回收废水中的有价金属。因此，它被认为是一种很有前景的处理含铬废水的技术。然而，由于合成温度高，该工艺尚未在工业上得到广泛应用。本文对常温合成铬铁矿的可行性进行了综合研究。研究了关键因素对出水水质和合成产品结晶行为和稳定性的影响。结果表明，废水中铬的去除率达99.0%以上，常温铁氧体处理后上清液铬浓度达到污水排放标准。增加曝气率，搅拌速度，和反应时间有利于形成稳定的铬铁矿。室温下铁氧体工艺得到的颗粒结构致密，颗粒最大尺寸达到52 μm。铬在合成过程中逐渐进入尖晶石晶体结构，合成铬铁矿的分子式可能为Fe_{3 - x} Cr _x O ₄，其中x约为0.30。提出了微观反应路径以阐明室温 条件下铬铁矿的合成机理。本研究为铁氧体工艺在含铬废水净化利用中的工业应用奠定了基础。