Laboratory of Algal Biology, Department of Botany, Banaras Hindu University, Varanasi 221 005, India.
Bioresour Technol. 2011 Jan;102(2):633-40. doi: 10.1016/j.biortech.2010.08.014. Epub 2010 Aug 6.
The present study explores the suitability of chemical reaction-based and diffusion-based kinetic models for defining the biosorption of Cu(II), Cd(II) and Pb(II) by Phormidium sp.-dominated mat. The time-course data of metal sorption by the test mat significantly (r2=0.932-0.999) fitted to the chemical reaction-based models namely pseudo-first-order, -second-order, and the general rate law. However, these models fail to accurately describe the kinetics of metal biosorption due either to prefixed order or unjustifiable change in rate constant and reaction order with varying concentrations of metal and biomass in the solution. The diffusion-based models, namely, the intra-particle diffusion model and the external mass transfer model fitted well to the time-course metal sorption data, thus suggesting involvement of both external and intra-particle diffusion processes in sorption of test metals by mat biomass. However, the Boyd kinetic expression clearly showed that the external mass transfer is the dominant process.
本研究探讨了基于化学反应和扩散的动力学模型在定义 Phormidium 主导垫中 Cu(II)、Cd(II) 和 Pb(II) 的生物吸附中的适用性。测试垫对金属的吸附时程数据与基于化学反应的模型（即准一级、准二级和一般速率定律）显著拟合（r2=0.932-0.999）。然而，由于固定的阶数或在溶液中金属和生物质浓度变化时速率常数和反应阶数的不合理变化，这些模型无法准确描述金属生物吸附的动力学。基于扩散的模型，即内扩散模型和外部传质模型，很好地拟合了金属吸附的时程数据，这表明测试金属被垫生物质吸附涉及到外部和内扩散过程。然而，Boyd 动力学表达式清楚地表明，外部传质是主要过程。
