title: Treatment of Reactive Black 5 by combined electrocoagulation-granular activated carbon adsorption-microwave regeneration process.
abstract: Treatment of an azo dye, Reactive Black 5 (RB5) by combined electrocoagulation-activated carbon adsorption-microwave regeneration process was evaluated. The toxicity was also monitored by the Vibrio fischeri light inhibition test. GAC of 100 g L(-1) sorbed 82% of RB5 (100 mg L(-1)) within 4h. RB5-loaded GAC was not effectively regenerated by microwave irradiation (800 W, 30s). Electrocoagulation showed high decolorization of RB5 within 8 min at pH(0) of 7, current density of 277 A m(-2), and NaCl of 1 g L(-1). However, 61% COD residue remained after treatment and toxicity was high (100% light inhibition). GAC of 20 g L(-1) effectively removed COD and toxicity of electrocoagulation-treated solution within 4h. Microwave irradiation effectively regenerated intermediate-loaded GAC within 30s at power of 800 W, GAC/water ratio of 20 g L(-1), and pH of 7.8. The adsorption capacity of GAC for COD removal from the electrocoagulation-treated solution did not significantly decrease at the first 7 cycles of adsorption/regeneration. The adsorption capacity of GAC for removal of both A(265) (benzene-related groups) and toxicity slightly decreased after the 6th cycle.
authors.affiliation: Department of Public Health, Chung-Shan Medical University, 110 Chen-Kuo N. Road, Taichung 402, Taiwan, ROC. shchang@csmu.edu.tw
authors.forename: Shih-Hsien
authors.initials: SH
authors.lastname: Chang
authors.forename: Kai-Sung
authors.initials: KS
authors.lastname: Wang
authors.forename: Hsiu-Hao
authors.initials: HH
authors.lastname: Liang
authors.forename: Hsueh-Yu
authors.initials: HY
authors.lastname: Chen
authors.forename: Heng-Ching
authors.initials: HC
authors.lastname: Li
authors.forename: Tzu-Huan
authors.initials: TH
authors.lastname: Peng
authors.forename: Yu-Chun
authors.initials: YC
authors.lastname: Su
authors.forename: Chih-Yuan
authors.initials: CY
authors.lastname: Chang
mesh_terms: D000327:Adsorption; D048908:Aliivibrio fischeri / Q000378:metabolism; D019149:Bioreactors; D002606:Charcoal / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods; D004564:Electrocoagulation; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D008872:Microwaves; D008956:Models, Chemical; D009282:Naphthalenesulfonates / Q000737:chemistry*; D013997:Time Factors; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D007220:Industrial Waste; D009282:Naphthalenesulfonates; D014874:Water Pollutants, Chemical; D002606:Charcoal; C063421:Remazol black B