Cobalt-Copper Oxide Catalysts for VOC Abatement: Effect of Co:Cu Ratio on Performance in Ethanol Oxidation

Abstract

The effect of the Co-Cu oxide catalysts composition on their physicochemical properties and performance in the deep oxidation of ethanol was studied. The catalysts with Co:Cu molar ratios of 4:1, 1:1, and 1:4 were obtained by calcination (4 h at 500 °C in air) of the coprecipitated precursors and characterized in detail using powder XRD, Raman spectroscopy, N2 physisorption, H2-TPR, and XPS. The powder XRD and Raman spectroscopy indicated the formation of Co3O4 and CuO mixtures rather than Co-Cu mixed oxides. The CuO promoted the Co3O4 reduction; the Co-Cu catalysts were reduced more easily than the single-component Co and Cu oxides and the main reduction maxima were shifted to lower temperatures with increasing cobalt content in the catalysts. The Co-Cu oxide catalyst with a Co:Cu molar ratio of 4:1 exhibited the best performance in ethanol gas-phase oxidation, showing the lowest T50 (91 °C) and T90(CO2) (159 °C) temperatures needed for 50% ethanol conversion and 90% conversion to CO2, respectively. The excellent catalytic properties of this Co-Cu oxide catalyst were ascribed to the synergistic effect of Co and Cu components. The high activity and selectivity of the Co-Cu catalyst was attributed to the presence of finely dispersed CuO particles on the surface of Co3O4.

New and Ultra‐Rapid Approach for Electrosynthesis of Highly Efficient Catalysts of Poly(para‐phenylenediamine) Supported Copper Oxide for Ethanol Oxidation in Alkaline Medium

“…[85,86] Many authors demonstrates in their studies that the presence of Copper or Copper oxide facilitates the CÀ C bond cleavage, resulting the complete oxidation of ethanol. [87][88][89][90][91][92] The results obtained by FTIR and cyclic voltammetry are in good agreement, the appearance of the peaks of CO and CO 2 originate from the cleavage of the bond CÀ C indicate the complete oxidation of the ethanol on Cu(OH) 2 À Cu 2 O@PpPD at I cste.…”

“…The most important peaks are located at 2113, 2299, and 2916 cm −1 , they are attributed to CO, CO 2 and C−H confirming the breakage of the C−C bond during ethanol oxidation [85,86] . Many authors demonstrates in their studies that the presence of Copper or Copper oxide facilitates the C−C bond cleavage, resulting the complete oxidation of ethanol [87–92] …”

Plasma Jet Sputtering as an Efficient Method for the Deposition of Nickel and Cobalt Mixed Oxides on Stainless-Steel Meshes: Application to VOC Oxidation

“…The broad band at 1090 cm −1 in the spectra of the NiCo4115 and NiCo4180 catalysts, together with the shoulder at 706 cm −1 in the spectrum of the NiCo4115 catalyst, can be attributed to the combination of transverse and longitudinal second-order optical vibrational modes of NiO [35]. Finally, the band at 193 cm -1 , which is particularly pronounced in the spectra of the NiCo4115 and NiCo4180 catalysts, can be attributed to the tetrahedral sites of Co3O4 [4].…”

“…In particular, oxides of Mn, Co, Cu, Ni, V, Cr, Fe, and their various mixtures are active catalysts in this process [1]. We previously shoed that cobalt oxide [2], Co-Mn mixed oxides [3], and Co-Cu oxides [4] prepared by precipitation and subsequent calcination or by magnetron sputtering are active in the complete oxidation of ethanol in air, arising, e.g., from pharmaceutical plants. In these processes, pelletized catalysts are most commonly used, but a significant part of the active mass in the pellets is unused in the process due to the large effect of internal diffusion limitations.…”

Electrodeposition of CoxNiy Thin Film and Its Catalytic Activity for Ethanol Electrooxidation

“…To enhance the performance of nickel for a better catalyst, bimetallic of another transition metal is combined with nickel [12]. Another metal that combines with nickel is cobalt [13]. Cobalt is one of the metal transitions that can be used as catalyst.…”