Regeneration of granular activated carbon with adsorbed trichloroethylene using wet peroxide oxidation.
The objective of this study is to clarify the regeneration of granular activated carbon (GAC) adsorbed trichloroethylene (TCE) using wet peroxide oxidation (WPO). TCE and TOC concentrations decreased during WPO, whereas Cl(-) accumulated in water indicating that TCE was not only decomposed but was also mineralized to Cl(-) and CO(2) using WPO. Regeneration efficiencies (q/q(0)) of GAC regenerated at 150, 165 and 180 degrees C (initial pH 4) were 0.36, 0.45, 0.48, respectively. In addition, regeneration efficiencies of GAC regenerated in the solution of various initial pH (2.5, 3.0, 4.0) at 180 degrees C were 0.71, 0.60, 0.48, respectively. These results suggest that regeneration of GAC is more effective at higher reaction temperature and lower initial pH of the solution. In the repeated regeneration of GAC, the adsorption capacity of GAC for TCE gradually decreased and regeneration efficiency of the regenerated GAC at sixth step was 0.40. The adsorption capacity loss of regenerated GAC is probably due to oxidation of GAC during WPO.
Okawa
Kiyokazu
K
Institute for Recycling and Environmental Control System, Fukuoka University, 10 Koyocho, Wakamatsu-ku, Kitakyushu 808 0002, Japan. okawa@fukuoka-u.ac.jp
Suzuki
Kazuyoshi
K
Takeshita
Toshihiro
T
Nakano
Katsuyuki
K
D000327:Adsorption; D002244:Carbon / Q000737:chemistry*; D002606:Charcoal / Q000737:chemistry*; D005374:Filtration; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010084:Oxidation-Reduction; D010545:Peroxides / Q000737:chemistry*; D013696:Temperature; D013997:Time Factors; D014241:Trichloroethylene / Q000737:chemistry / Q000378:metabolism*; D014865:Waste Disposal, Fluid
D010545:Peroxides; D002606:Charcoal; D014241:Trichloroethylene; D002244:Carbon