MODIFIED AMORPHOUS SiO2 FROM Zr-CONTAINING SILICA RESIDUE: A PROMISING WAY OF RECYCLING USEFUL MATERIALS AS WELL AS REMOVING Cr(VI) FROM WATER

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 degrees 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.

Automated summary

Amorphous SiO2 purified from Zr-containing silica residue and modified by CTAB was used for Cr(VI) adsorption. The optimal pH value for adsorption was found to be 3, with 60 minutes of adsorption time required at 45 degrees Celsius using 10 g/L of modified SiO2. The adsorption isotherm and process were interpreted using Langmuir and pseudo-second-order kinetic models, providing an effective option for waste water treatment and material recycling.