黑曲霉发酵菌渣对臧红T的吸附研究

Adsorption of Safranine T by Aspergilus niger Biomass Waste

将糖化酶发酵生产过程中产生的黑曲霉菌渣作为一种复合吸附剂进行了染料吸附研究,以挖掘其吸附潜力。首先对菌渣的理化性质进行了分析,然后以臧红T为模型染料,考察了几种因素(接触时间、溶液温度、吸附剂量、初始浓度和盐离子)对吸附的影响,并将所得数据用等温吸附方程、动力学方程和热力学方程进行了模型拟和。结果表明,吸附可在2 h内达到平衡,吸附过程符合准二级动力学模型,属于化学吸附,膜扩散模型比内扩散模型更适合解释吸附行为;温度对吸附有促进作用,吸附过程是一个自发的吸热反应;通过Langmuir方程可计算出最大单分子层吸附容量为166.67 mg/g,但Freundlich能更好的描述吸附行为,说明菌渣表面存在多个不同的吸附位点。此外,菌渣投加量和钠离子浓度均可影响吸附效果,染料去除率最高可达91%。

The present work aims to investigate the adsorption of dye safranine T by Aspergillus niger biomass waste from amylaseproduction as novel composite adsorbent. The biomass waste was first characterized concerning its physico-chemical properties and thenevaluated for its potential of adsorbing safranine T under different conditions,namely contact time,temperature,sorbent dosage,initialdye concentration and metal ion. The isotherms,dynamics,and thermodynamics were fitted with the above data,which showed that pseudosecond order dynamics equation better described the adsorption with equilibrium achieved within 2 h,suggesting it was chemosorption,andfilm diffusion model was more suitable to explain the adsorption than internal diffusion model. Higher temperatures significantly promoted dyeremoval,and adsorption was both spontaneous（ΔG° 0）and endothermic（ΔH° 0）. The maximal monolayer adsorption capacity wascalculated to be around 166.67 mg/g through Langmuir equation while Freundlich was more suitable to explain the adsorption,indicating thatthere were multiple absorptive sites on the surface of biomass waste. In addition,sorbent dosage and sodium ion concentration both impactedadsorption with the highest removal rate of 91%.