The amorphous SiO₂, which is purified from Zr-containing silica residue, was modified by CTAB before the adsorption of Cr(VI). The impact of different variables, such as solution pH value, adsorption time, adsorption temperature, and adsorbent dosage were investigated on the Cr(VI) removal from solution. The results show that the optimal pH value for Cr(VI) adsorption is 3. And 60 min is needed for the adsorption with 10 g/L of modified amorphous SiO₂ at 45∘C. The acquired adsorption isotherm and the adsorption process can be interpreted by Langmuir model and pseudo-second-order kinetic model, respectively. This paper provides an effective option for waste water treatment as well as a way of recycling useful materials from the discarded Zr-containing silica residue.

中文翻译：

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从含 Zr 二氧化硅残渣中改性无定形 SiO2：一种回收有用材料以及从水中去除 Cr(VI) 的有前途的方法

从含 Zr 的二氧化硅残留物中提纯的无定形 SiO _{2在吸附 Cr(VI) 之前通过 CTAB 改性。}研究了溶液pH值、吸附时间、吸附温度和吸附剂用量等不同变量对溶液中Cr(VI)去除率的影响。结果表明，Cr(VI)吸附的最佳pH值为3。10 g/L的改性无定形SiO ₂吸附时间为60 min 。45∘C.获得的吸附等温线和吸附过程可以分别用Langmuir模型和准二级动力学模型解释。本文为废水处理提供了一种有效的选择，以及一种从废弃的含锆二氧化硅残渣中回收有用材料的方法。