JIANG Yu,SUN Kang,WANG Dong-tian,et al. Removal of Cr(Ⅵ) in Wastewater by Modified Waterworks Sludge Supported Nanoscale Zero-valent Iron [J].China Water & Wastewater,2020,36(13):20-25.
Removal of Cr(Ⅵ) in Wastewater by Modified Waterworks Sludge Supported Nanoscale Zero-valent Iron
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第36卷
Number:
13
Page:
20-25
Column:
Date of publication:
2020-07-01
- Keywords:
- waterworks sludge; modification; nanoscale zero-valent iron; Cr(Ⅵ)
- Abstract:
-
Modified waterworks sludge was prepared by high temperature heat treatment and hydrochloric acid activation. The modified waterworks sludge supported nanoscale zero-valent iron (MWS-nZVI) was prepared by reduction of Fe3+ with NaBH4 through liquid phase chemical reduction method, and the adsorbent was applied for the removal of Cr(Ⅵ) in wastewater. The adsorption performance of MWS-nZVI was compared with that of waterworks sludge supported nanoscale zero-valent iron (WS-nZVI), and the effects of pH, adsorbent dosage and initial concentration on adsorption of Cr(Ⅵ) were evaluated. Physical properties and chemical composition of the adsorbent were analyzed by different kinds of characterization methods (SEM, XPS and FTIR). The results indicated that MWS-nZVI had a good removal efficiency on Cr(Ⅵ). When the dosage was 0.3 g/L, pH value was 2, initial concentration of Cr(Ⅵ) was 20 mg/L and reaction time was 3.5 h, the maximum adsorption capacity was 26.0 mg/g. The characterization results showed that MWS-nZVI had a large specific surface area and a better loading effect on nanoscale zero-valent iron. The Freundlich adsorption isotherm equation was more suitable to simulate the removal process of Cr(Ⅵ) by MWS-nZVI.
Last Update:
2020-07-01