Inhibition on acidogenesis of dairy wastewater by zinc and copper.
Acidogenesis of dairy wastewater produced volatile fatty acids, mainly acetate and propionate, plus hydrogen as by-product. Zinc (Zn) inhibited acidogenesis at concentrations over 10 mg l(-1); but at 10 mg l(-1), or less, it enhanced acidogenesis slightly. On the other hand, copper (Cu) inhibited acidogenesis at all tested concentrations ranging 5-400 mg l(-1). Production of acetate was inhibited by both metals at all concentrations; but production of propionate and hydrogen was favored at low concentrations of Zn (up to 80 mg l(-1)) and Cu (up to 40 mg l(-1)). Production of hydrogen corresponded with the degradation of carbohydrate and the production of propionate. Overall, Cu was 1.4-4.3 folds more toxic than Zn, according to the overall production patterns of fatty acids and hydrogen as well as degradation patterns of carbohydrate and protein.
Yu
H Q
HQ
Department of Applied Chemistry, The University of Science & Technology of China, Hefei, Anhui.
Fang
H P
HP
D002241:Carbohydrates / Q000032:analysis; D002245:Carbon Dioxide / Q000032:analysis; D003300:Copper / Q000009:adverse effects / Q000737:chemistry*; D003612:Dairying; D005232:Fatty Acids, Volatile / Q000032:analysis; D006859:Hydrogen / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D008697:Methane / Q000032:analysis; D009584:Nitrogen / Q000032:analysis; D011506:Proteins / Q000032:analysis; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical; D018508:Water Purification / Q000379:methods*; D015032:Zinc / Q000009:adverse effects / Q000737:chemistry*
D002241:Carbohydrates; D005232:Fatty Acids, Volatile; D011506:Proteins; D014874:Water Pollutants, Chemical; D002245:Carbon Dioxide; D003300:Copper; D006859:Hydrogen; D015032:Zinc; D009584:Nitrogen; D008697:Methane