YOU Kun,FAN Wei-li,FU Jin-xiang,et al.Fluorine and Iron Removal Efficiency of Manganese-loaded Activated Alumina[J].China Water & Wastewater,2020,36(23 23):42-51.
Fluorine and Iron Removal Efficiency of Manganese-loaded Activated Alumina
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第36卷
Number:
23 23
Page:
42-51
Column:
Date of publication:
2020-12-01
- Abstract:
- In order to solve the problem of excessive fluorine and iron in groundwater-type drinking water source in northern China, manganese-loaded activated alumina (MAA) was prepared by modification with aluminum sulfate and manganese sulfate to simultaneously remove fluorine and iron from groundwater. Influencing factors, removal mechanism and regeneration performance of MAA removing fluorine and iron were analyzed by static and dynamic tests. Surface of the modified activated alumina presented irregular convex thorn-like granular structure and had characteristic peaks of manganese oxides and hydroxides. Alkaline manganese oxide was successfully attached to the surface of the alumina, and its removal efficiency of fluorine was 70% higher than that before modification. The removal efficiencies of iron ions and fluorine ions in effluent reached 80.5% and 81%. The optimal parameters for removing fluoride and iron ions by manganese activated alumina adsorbent were obtained by Box-Behnken response surface test model, which were as follows: adsorption time of 8 h, pH value of 4 and temperature of 25 ℃. Among them, the pH value had the greatest influence on removal of fluorine and iron. Kinetics of fluoride ions adsorbed by MAA conformed to the pseudo-second-order kinetic equation. The adsorption isotherm conformed to the Freundlich model, indicating that the adsorption process was dominated by multi-layer chemical adsorption. The dynamic test results showed that penetration time of fluoride in the effluent treated by manganese activated alumina was extended from 11 h to 27 h, and the reaction time of iron ion was shortened from 60 h to 5 h. The removal efficiency of fluorine and iron by MAA was greatly improved. After three regenerations, fluoride ion adsorption capacity of the MAA filter column was reduced from 0.7 mg/g to 0.6 mg/g. The adsorption capacity of the regenerated MAA did not decrease significantly.
Last Update:
2020-12-01