title: Environmental application of millimeter-scale sponge iron (s-Fe(0)) particles (II): the effect of surface copper.
abstract: To enhance the catalytic reactivity of millimeter-scale particles of sponge iron (s-Fe(0)), Cu(2+) ions were deposited on the surface of s-Fe(0) using a simple direct reduction reaction, and the catalytic properties of the bimetallic system was tested for removal of rhodamine B (RhB) from an aqueous solution. The influence of Cu(0) loading, catalyst dosage, particle size, initial RhB concentration, and initial pH were investigated, and the recyclability of the catalyst was also assessed. The results demonstrate that the 3∼5 millimeter s-Fe(0) particles (s-Fe(0)(3∼5mm)) with 5wt% Cu loading gave the best results. The removal of RhB followed two-step, pseudo-first-order reaction kinetics. Cu(0)-s-Fe(0) showed excellent stability after five reuse cycles. Cu(0)-s-Fe(0) possesses great advantages compared to nanoscale zero-valent iron, iron power, and iron flakes as well as its bimetals. The surface Cu(0) apparently catalyzes the production of reactive hydrogen atoms for indirect reaction and generates Fe-Cu galvanic cells that enhance electron transfer for direct reaction. This bimetallic catalyst shows great potential for the pre-treatment of recalcitrant wastewaters. Additionally, some oxides containing iron element are selected to simulate the adsorption process. The results prove that the adsorption process of FeOOH, Fe2O3 and Fe3O4 played minor role for the removal of RhB.
authors: South China Institute of Environmental Sciences, The Ministry of Environmental Protection of the PRC, Guangzhou 510655, PR China. Electronic address: juyongming@scies.org.
authors: Yongming
authors: Y
authors: Ju
authors: South China Institute of Environmental Sciences, The Ministry of Environmental Protection of the PRC, Guangzhou 510655, PR China. Electronic address: liuxiaowen@scies.org.
authors: Xiaowen
authors: X
authors: Liu
authors: South China Institute of Environmental Sciences, The Ministry of Environmental Protection of the PRC, Guangzhou 510655, PR China.
authors: Runlong
authors: R
authors: Liu
authors: South China Institute of Environmental Sciences, The Ministry of Environmental Protection of the PRC, Guangzhou 510655, PR China.
authors: Guohua
authors: G
authors: Li
authors: South China Institute of Environmental Sciences, The Ministry of Environmental Protection of the PRC, Guangzhou 510655, PR China.
authors: Xiaoyan
authors: X
authors: Wang
authors: South China Institute of Environmental Sciences, The Ministry of Environmental Protection of the PRC, Guangzhou 510655, PR China.
authors: Yanyan
authors: Y
authors: Yang
authors: South China Institute of Environmental Sciences, The Ministry of Environmental Protection of the PRC, Guangzhou 510655, PR China.
authors: Dongyang
authors: D
authors: Wei
authors: South China Institute of Environmental Sciences, The Ministry of Environmental Protection of the PRC, Guangzhou 510655, PR China.
authors: Jiande
authors: J
authors: Fang
authors: Environmental Engineering and Science Program, Department of Biomedical, Chemical and Environmental Engineering (DBCEE), University of Cincinnati, Cincinnati, Ohio 45221-0012, USA. Electronic address: dionysios.d.dionysiou@uc.edu.
authors: Dionysios D
authors: DD
authors: Dionysiou
mesh_terms: D000327:Adsorption; D002384:Catalysis; D004396:Coloring Agents / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D010084:Oxidation-Reduction; D012235:Rhodamines / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D004396:Coloring Agents; D012235:Rhodamines; D014874:Water Pollutants, Chemical; D003300:Copper; D007501:Iron; C029773:rhodamine B
keywords: Copper–iron catalysts; Rhodamine B; Sponge iron; Textile wastewater; Zero-valent iron