重金属生物吸附的吸附模型

排污系统中的重金属通过生物的方法进行吸附除掉，是一种重金属回收和再利用的较为有效治理方法。本研究通过热平衡的机理分析，采用普通的物质吸附模型，通过大量的实验数据处理，得到了重金属吸附脱俯的数学模型。该模型具有较好计算与实验数据的吻合性。但是实验结果也表明，生物吸附模型不适用于计算在生物质中的重金属离子脱附量，即重金属生物吸附模型没有满足可逆性。这一点在使用该模型时需要给予考虑。因此吸附的机理分析还需要结合实践过程的热力学平衡数据来进行分析回归。

Adsorption models for heavy metal biosorption

Heavy metal biosorption is an effective process for the removal and recovery of heavy metal ions.Equilibrium isotherms obtained experimentally are usually correlated empirically with commonly used adsorption models, without considering the underlying mechanisms of biosorption.Commonly used models for correlating biosorption isotherm data are briefly reviewed and the use of the adsorption models in correlating the desorption processes is analysed.A set of biosorption/desorption experiments for a marine alga derived biosorbent are carried out to test the use of the adsorption models in the desorption process.Experimental data indicate that the amount of the heavy metal ions desorbed from the biomass could not be calculated with the adsorption models.This suggests that the empirical use of adsorption models in the correlation may not be valid when the reversibility of the biosorption equlibrium in the desorption process needs to be considered.Therefore, mechanism based biosorption models are needed for better correlation of equilibrium isotherm data.