Departamento de Química, Universidade Federal de Lavras, Caixa Postal 37, CEP 37200-000 Lavras, MG, Brazil.
J Environ Manage. 2013 Sep 30;127:206-11. doi: 10.1016/j.jenvman.2013.05.017. Epub 2013 Jun 5.
A friendly environmental material for organic contaminants removal was prepared in this work: small particles of iron oxide dispersed over activated carbon from coffee waste for Fenton-like application. The materials were characterized by means of XRD, N2 physisorption, Mössbauer spectroscopy and H2 pulse titration. The composites showed very good catalytic performances for methylene blue organic dye oxidation. The small goethite particles are the predominant iron oxide phase in the composites. The apparent surface area is quite high and is not very affected after iron impregnation. ESI-MS studies revealed that the dye removal occurs through a Fenton-type system by the composite whereas for the activated carbon the dye removal occurs mainly via adsorption. The iron leaching from the catalysts was negligible, less than 0.5 ppm, which evidences the occurrence of a heterogenous oxidation process. The catalyst was very active for methylene blue oxidation and could be repeatedly used for at least 5 cycles. The catalyst was also active in the oxidation of other organic compounds, such as caffeine and atrazine.
将氧化铁小颗粒分散在咖啡废料活性炭上，用于类芬顿应用。通过 XRD、N2 物理吸附、Mössbauer 光谱和 H2 脉冲滴定对材料进行了表征。复合材料对亚甲基蓝有机染料氧化表现出非常好的催化性能。复合材料中主要的氧化铁相是针铁矿小颗粒。比表面积相当高，铁浸渍后变化不大。ESI-MS 研究表明，染料去除是通过复合材料的类芬顿体系发生的，而对于活性炭，染料去除主要通过吸附发生。催化剂中铁的浸出可以忽略不计，小于 0.5ppm，这表明发生了异相氧化过程。催化剂对亚甲基蓝的氧化非常有效，至少可以重复使用 5 次。该催化剂在氧化其他有机化合物，如咖啡因和莠去津时也具有活性。
