废水中GaAs、Ga^(3+)、Ge^(4+)对活性污泥脱氢酶的影响及其抑制动力学

EFFECTS OF GaAs,Ga^(3+) AND Ge^(4+) IN WASTE WATER ON ACTIVITIES OF DEHYDROGENASES OF ACTIVATED SLUDGE

以活性污泥脱氢酶的活性作为毒性指标,研究了半导体材料GaAs、Ga^(3+)、Ge^(4+)对活性污泥活性的抑制影响,并用Hg^(2+)作为参比材料;同时对抑制动力学也作了初步研究。实验表明,GaAs、Ga^(3+)、Ge^(4+)及Hg^(2+)的10％抑制浓度分别为45.00,371.63,0.13ppm/gMLSS,GaAs、Ga^(3+)、Ge^(4+)和Hg^(2+)在浓度分别为180,700,250和1.25ppm/g MLSS时的抑制常数分别为1.30×10^(-3),7.05×10^(-3),6.12×10^(-3)和5.49×10^(-3)mmol,且其抑制类型均属可逆非竞争性抑制。

The effects of GaAs, Ga3+ and Ge4+ in wastewater from semiconductor material production on the activities of dehydrogenases of activated sludge (MLSS of 2000 mg/L) were studied. The concentrations for 10% inhibition were 0.13, 45, 371 and 63 ppm/g MLSS for Hg2+, GaAs, Ga3+ and Ge4+, respectively. The 50% inhibition produced by Hg2+ at 2.7 ppm/gMLSS,25% by GaAs at 170ppm/gMLSS and Ge4+ at 228ppm/gMLSS. No competitive effects was found for the four inhibitors. The inhibition constants(Ki) of Hg2+, GaAs, Ga3+ and Ge4+ were 5.49×10-3 mmo1(1.25ppm/gMLSS), 1.30 mmol (180ppm/gMLSS), 7.05 mmol (700ppm/gMLSS) and 6.12mmol (250 ppm/gMLSS), respectively.