Utilization of steel-making slag for the uptake of ammonium and phosphate ions from aqueous solution.
Steel-making slag, a waste by-product of the Steel Industry, constitutes a major disposal problem. In the present study, excellent adsorbent materials for reducing eutrophication in wastewaters have been prepared from this slag. Heated samples of acid-treated slag and mixtures of slag with kaolinite and Al(OH)(3) were examined to determine their uptake capacities for NH(4)(+) and PO(4)(3-) from aqueous solutions. In general, the equilibrium pH of the solution increased in comparison to initial pH with the uptake of target ions, the sample activated slag-Al(OH)(3) showing the smallest change. The highest PO(4)(3-) uptake capacity was obtained with the slag-Al(OH)(3) mixture heated at 900 degrees C whereas the highest uptake of NH(4)(+) was found in the slag-Al(OH)(3) mixture heated at 800 degrees C. The uptake rates for PO(4)(3-) and NH(4)(+) by the slag-Al(OH)(3) mixture heated at 900 degrees C were 2.91 and 0.65 micro mol/(g min), respectively. It was shown that heating slag composites prior to incorporation into wastewater treatment filters resulted in an increased degree of NH(4)(+) and PO(4)(3-) uptake.
Jha
Vinay Kumar
VK
Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, Meguro, Tokyo, Japan. vinayj2@yahoo.com
Kameshima
Yoshikazu
Y
Nakajima
Akira
A
Okada
Kiyoshi
K
D000327:Adsorption; D007700:Kinetics; D010710:Phosphates / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D012996:Solutions; D013232:Steel; D014867:Water; D014961:X-Ray Diffraction
D010710:Phosphates; D000644:Quaternary Ammonium Compounds; D012996:Solutions; D014867:Water; D013232:Steel