PDF(Pubmed)
Abstract：
The pristine CMK-3 carbon was ozonized and then chemically modified by the Zr and Fe compounds. The synthesized carbonaceous materials were characterized with physicochemical methods. The obtained carbons had a high specific surface area (ca. 800 m2 g-1) and an acidic surface. The Cr(VI) adsorption properties of the oxidized and Zr/Fe-modified carbon were studied. The highest static adsorption capacity towards Cr(VI) ions was evaluated for Zr/Fe-modified carbon (50.1 mg g-1) at pHeq = 5.8 after 240 min. The Elovich and Freundlich theoretical models were well fitted to the Cr(VI) adsorption kinetic and isotherm data on the Zr/Fe-modified CMK-3-type carbon. The leading Cr(VI) adsorption mechanism acting on the Zr/Fe-modified carbon was probably based on the redox reactions between Cr(VI) and the carbonaceous surface. Electrostatic attraction and surface complexation processes could also occur during Cr(VI) adsorption in the studied system. The effect of the competitive anions on the concentration level, such as in the galvanic wastewater for Cr(VI) adsorption onto chemically modified carbon, was negligible. The HCl and HNO3 media were insufficient for the Zr/Fe-modified carbon regeneration after Cr(VI) adsorption. The Zr/Fe-modified carbon was successfully applied for the efficient (>90%) Cr(VI) removal from the model galvanic wastewater.
摘要：
原始CMK-3碳被臭氧化，然后被Zr和Fe化合物化学改性。用物理化学方法对合成的碳质材料进行了表征。获得的碳具有高比表面积（约800m2g-1）和酸性表面。研究了氧化和Zr/Fe改性碳的Cr（VI）吸附性能。在240分钟后，在pHeq=5.8时，对Zr/Fe改性的碳（50.1mgg-1）评估了对Cr（VI）离子的最高静态吸附能力。Elovich和Freundlich理论模型很好地拟合了Zr/Fe改性的CMK-3型碳上的Cr（VI）吸附动力学和等温线数据。作用于Zr/Fe改性碳的主要Cr（VI）吸附机理可能是基于Cr（VI）与碳质表面之间的氧化还原反应。在所研究的系统中，Cr（VI）吸附过程中也可能发生静电吸引和表面络合过程。竞争阴离子对浓度水平的影响，例如在电镀废水中，将Cr(VI)吸附到化学改性碳上，微不足道。HCl和HNO3介质不足以在Cr（VI）吸附后进行Zr/Fe改性的碳再生。Zr/Fe改性的碳被成功地应用于从模型的电镀废水中高效地(>90%)去除Cr(VI)。
