[Characterization of Cr (VI) removal and total Cr equilibrium adsorption by sulfate reducing granular sludge in stimulant wastewater].
Sulfate reducing granular sludge (SRGS) cultivated in small scale EGSB reactor was used for Cr (VI) removing. Characterization of Cr (VI) removal and total Cr equilibrium adsorption was studied, and the adsorption isotherm was fitted. Results showed that removal of Cr (VI) was in connection with the structure and chemical composition of SRGS and several environmental factors. The Cr (VI) removal rate increased with the dosage of granular sludge; the increasing of oscillation speed and temperature could enhance Cr (VI) removal and total Cr adsorption, but while the oscillation speed reached 150 r x min(-1) or the temperature came to 40 degrees C, the physical structure of granular sludge would be affected and the granular sludge discrete, and total Cr equilibrium adsorption decreased; lower pH value caused higher Cr (VI) removal rate, however the sulfate on the surface of granular sludge was affected by lower pH value easily and would translate into H2S, then total Cr adsorption rate decreased. Cr (VI) removal would be influenced by physical, chemical and biological factors, and the process included reduction and adsorption mainly. The maximum adsorption of total Cr by granular sludge was 6.84 mg x g(-1), and the total Cr adsorbing process fitted in with Langmuir adsorption isotherm.
South China Institute of Environmental Sciences, Ministry of Environmental Protection of the People's Republic of China, Guangzhou 510655, China. luojun@scies.org
Jun
J
Luo
Zhi-Hua
ZH
Pang
Yong-You
YY
Hu
Hai-Tao
HT
Zhong
Jian-Yu
JY
Chen
Fang-Min
FM
Lin
D000327:Adsorption; D019149:Bioreactors / Q000382:microbiology; D002857:Chromium / Q000302:isolation & purification* / Q000378:metabolism; D007220:Industrial Waste / Q000517:prevention & control*; D010316:Particle Size; D012722:Sewage / Q000737:chemistry*; D013431:Sulfates / Q000737:chemistry*
D007220:Industrial Waste; D012722:Sewage; D013431:Sulfates; D002857:Chromium; C074702:chromium hexavalent ion