Universidad Autónoma del Estado de México, Facultad de Química, Toluca, Mexico.
Environ Sci Pollut Res Int. 2012 Jan;19(1):177-85. doi: 10.1007/s11356-011-0537-x. Epub 2011 Jun 25.
The present work was carried out to investigate the effects of temperature, initial pH, initial concentration, and contact time on the biosorption of lead (Pb) and cadmium (Cd) by modified stalk sponge of Zea mays using a batch technique.
The biomass was chemically modified with a 0.1 M NaCl solution. The lead and cadmium sorption process was evaluated at 20°C, 30°C, 40°C, and 50°C.
The results showed that the modified stalk sponge of Z. mays had a good capacity for biosorption of Pb(II) and Cd(II). The kinetic behavior was described by the pseudo-second-order model for both metallic species. The experimental isotherms obtained at different temperatures were fit with Langmuir and Freundlich models. Thermodynamic parameters ΔH(0) and ΔS(0) were calculated using the van't Hoff equation, and the results show that Pb(II) and Cd(II) sorption by modified stalk sponge of Z. mays is an exothermic and spontaneous process.
本研究采用批处理技术，考察温度、初始 pH 值、初始浓度和接触时间对玉米秸秆海绵改性后对铅（Pb）和镉（Cd）的吸附作用的影响。
采用 0.1 M NaCl 溶液对生物质进行化学改性。在 20°C、30°C、40°C 和 50°C 下评估了铅和镉的吸附过程。
结果表明，改性后的玉米秸秆海绵对 Pb(II) 和 Cd(II) 具有良好的吸附能力。动力学行为均符合两种金属物种的伪二级模型。在不同温度下获得的实验等温线均符合朗缪尔和弗伦德利希模型。利用范特霍夫方程计算热力学参数ΔH(0)和ΔS(0)，结果表明，改性玉米秸秆海绵对 Pb(II) 和 Cd(II) 的吸附是一个放热和自发的过程。
