Adsorptive removal of Cd(II) from aqueous solution using natural and modified rice husk.
In this study, the natural and modified rice husk were tested to remove Cd(II) ions from water. The modified rice husk was prepared by being treated with alkali. The results showed the Cd(II) adsorption capacity was 73.96, 125.94 mg/g, respectively, for the natural and modified rice husk. The modified rice husk had faster kinetics and higher adsorption capacities than the natural rice husk, which can be attributed to the surface structural changes of the material. Equilibrium adsorption data are more consistent with the Langmuir isotherm equation than with the Freundlich equation. The Cd(II) adsorption on the two adsorbents tends to increase with the increase of pH. The optimum pH for Cd(II) adsorption is 6.5. Both pseudo-first-order and pseudo-second-order equations were able to describe properly the kinetics of Cd(II) adsorption. The desorbability of Cd(II) is about 95.8-99.1% by 0.1M HCl solution.
Ye
Hengpeng
H
Institute of Environment Engineering and Science, School of Chemistry and Material Science, Key Laboratory for Catalysis and Materials Science of the State Ethnic Affairs Commissions & Ministry of Education, South Central University for Nationalties, Wuhan 430074, China. yehengpeng@126.com <yehengpeng@126.com>
Zhu
Qing
Q
Du
Dongyun
D
D000327:Adsorption; D001673:Biodegradation, Environmental; D002104:Cadmium / Q000737:chemistry* / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D012275:Oryza / Q000737:chemistry*; D010944:Plants / Q000378:metabolism; D012996:Solutions; D013055:Spectrophotometry, Infrared / Q000379:methods; D017550:Spectroscopy, Fourier Transform Infrared; D014865:Waste Disposal, Fluid / Q000379:methods; D014867:Water / Q000737:chemistry; D014873:Water Pollutants / Q000302:isolation & purification; D018508:Water Purification / Q000379:methods
D012996:Solutions; D014873:Water Pollutants; D002104:Cadmium; D014867:Water