Fe和Fe2+对混合细菌产氢发酵的影响

在研究Fe粉剂量和Fe²⁺浓度对混合细菌产氢发酵的影响基础上,确定Fe和Fe²⁺促进混合细菌产氢能力的最佳阈值,并对乙醇型发酵菌群在不同Fe粉和Fe²⁺浓度下的产氢量和最大比产氢速率进行考察和对比.结果表明,Fe粉和Fe²⁺对乙醇型发酵菌群的产氢能力均有明显的促进作用.以葡萄糖为底物,投加Fe²⁺试验中,Fe²⁺浓度200mg/L获得最大产氢量143.7mL/g,较对照组提高32%;Fe²⁺浓度50mg/L获得单位VSS最大比产氢速率21.2 mL/(h·g),较对照组提高33%.投加单质Fe试验中,Fe粉剂量1000mg/L获得最大产氢量156.1mL/g,较对照组提高44%;Fe粉剂量500mg/L获得单位VSS最大比产氢速率23.5mL/(h·g),较对照组分别提高47%.单质Fe浓度高于50mg/L时,对发酵菌群产氢的促进作用要优于同浓度下的Fe²⁺.同时对混合细菌中铁的全量和形态分布进行了考察.

Effect of Fe and Fe2+ on Hydrogen Production Capacity with Mixed Culture

The effects of Fe and Fe²⁺ concentration in the external environment on hydrogen production capacity of ethanol type fermentative microorganism flora were investigated. The optimum range of Fe and Fe²⁺ concentration enhanced hydrogen production were obtained and the characteristic of fermentation types at different concentration of Fe and Fe²⁺ were discussed. It was demonstrated that both Fe and Fe²⁺ were able to enhance the hydrogen production capacity of microorganism flora. The maximum hydrogen production yield of 143.7mL·g^-1 glucose and the maximum specific hydrogen production rate 21.2mL·(h·g)^-1 were obtained at Fe²⁺ concentration of 200mg·L^-1 and 50mg·L^-1 . The maximum hydrogen production yield of 156 1mL·g^-1 glucose and the maximum specific hydrogen production rate 23 5mL·(h·g)^-1 were obtained at Fe concentration of 1000mg·L^-1 and 500mg·L^-1 . At the same concentration, the enhancement of Fe is better than Fe²⁺ when the concentration is higher than 50 mg·L^-1. A sequential extraction technique was used to represent arbitrary divisions between different metal forms of Fe²⁺ in the mixed culture.