Hubei Province Research Center of Engineering Technology for Utilization of Botanical Functional Ingredients, Hubei Engineering University, Xiaogan, 432000, China.
College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
Environ Sci Pollut Res Int. 2020 Mar;27(8):8028-8033. doi: 10.1007/s11356-019-07535-3. Epub 2020 Jan 2.
Agricultural wastes have promising potential for the production of low-cost and sustainable adsorbents for heavy metals, while the characteristics of those biosorbents and the stability of the passivated heavy metals under natural conditions need to be studied further. In this paper, the oilseed rape plant after seed harvesting was divided into three parts: root (RT), stem (ST), and pod (PD). The isotherm adsorption of cadmium (Cd(II)) on the biomass was conducted. In practice, the biomass was aged in the Cd(II)-contaminated soil, and the concentration of Cd(II) in the leachate was measured after the continuous eluent of typical acid rain. The components and elements of the biomass were determined for the analysis of the differences between the immobilization abilities of the biomass. Results showed the CC (corn cob, as a comparison), ST, RT, and PD had the adsorption capacities of 6.34, 7.58, 9.22, and 9.87 mg/g for Cd(II) through the Langmuir fitting of the isothermal adsorption experiments, respectively. The leached Cd(II) were reduced 1063, 2073, 2824, and 3621 μg by CC, ST, RT, and PD biomass aging, respectively. Compared that by CC, the immobilization differences between the biomass in soil were much greater than that in isotherm adsorption, indicating the biosorption ability of rape biomass was enlarged during the 30 days of aging. Nitrogen, phosphorus, and sulfur contents showed sequences as pod>root>stem and had high correlations with the reduced amount of leached Cd(II), which indicated protein might be beneficial for the enhancement of adsorption/immobilization in the soil.
农业废弃物具有很大的潜力，可以用来生产低成本、可持续的重金属吸附剂，而这些生物吸附剂的特性以及在自然条件下被固定的重金属的稳定性还需要进一步研究。在本文中，我们将油菜籽收获后的植物分为三部分：根（RT）、茎（ST）和荚（PD）。研究了生物质对镉（Cd(II)）的等温吸附作用。在实际中，将生物质在 Cd(II)污染的土壤中老化，然后用典型的酸雨连续淋洗，测量浸出液中 Cd(II)的浓度。对生物质的成分和元素进行了测定，分析了生物质固定能力的差异。结果表明，通过等温吸附实验的朗缪尔拟合，CC（玉米芯，作为对照）、ST、RT 和 PD 对 Cd(II)的吸附容量分别为 6.34、7.58、9.22 和 9.87 mg/g。CC、ST、RT 和 PD 生物质老化分别使淋出的 Cd(II)减少了 1063、2073、2824 和 3621μg。与 CC 相比，生物质在土壤中的固定化差异比等温吸附中的差异大得多，这表明油菜生物量在 30 天的老化过程中生物吸附能力得到了增强。氮、磷和硫含量的顺序为荚>根>茎，且与淋出 Cd(II)的减少量有很高的相关性，这表明蛋白质可能有利于提高土壤中的吸附/固定能力。
