Oxidative regeneration study of spent V2O5 catalyst from sulfuric acid manufacture
- 16 Downloads
In this work, the efficiency of the regeneration process of spent V2O5 catalyst from sulfuric acid plant under different atmospheres (5%O2/N2 or air) was evaluated. Temperature-programmed results showed that the observed reduction profiles of the samples are attributed to the reduction of amorphous V+5 and low-valence V+5−x species at low temperatures followed by the reduction of their crystalline structures at high temperatures. Significantly low values of SO2 conversion of the spent samples can be explained by the significant drop in quantity of all vanadium species, coupled with their structural change to more thermally stable forms. It was found that the exposure of the spent catalyst to 5%O2/N2 stream at 550 °C for 1 h allowed at first the re-oxidation of amorphous low-valence V species and second the dissolution of crystalline low-valence V species, thus resulted in recovery of their catalytic activity for SO2 oxidation. However, the regeneration in air was less effective than in 5%O2/N2 stream. This is supposedly due to the differential behaviors of the spent sample in different oxidative streams toward re-oxidizing low-valence V species and re-dissolving V precipitates.
KeywordsV2O5 Oxidative regeneration SO2 oxidation reaction Temperature-programmed reduction
This work is supported by The Ministry of Industry and Trade of the Socialist Republic of Vietnam under Grant 06/HD-DT.06.14/CNMT.
Compliance with ethical standards
Conflict of interest
On behalf of all authors, the corresponding author states that there is no conflict of interest.
- 1.Louie DK (2005) Handbook of sulphuric acid manufacturing. DKL Engineering, ThornhillGoogle Scholar
- 3.MECS Standard Sulfuric Acid Catalysts MSDS, Monsanto Enviro-Chem Systems Inc. (2011)Google Scholar
- 4.King M, Moats M, Davenport WGI (2013) Sulfuric acid manufacture: analysis, control and optimization, 2nd edn. Elsevier, New YorkGoogle Scholar
- 6.Hansen NH, Fehrmann R, Bjerrum NJ (1982) Complex formation in pyrosulfate melts. 1. Potentiometric, cryoscopic, and spectrophotometric investigations of the systems potassium disulfate-potassium sulfate and potassium disulfate-potassium sulfate-vanadium pentoxide in the temperature range 410–450 °C. Inorg Chem 21:744–752CrossRefGoogle Scholar
- 15.Wang CB, Deo G, Wachs IE (1998) Characterization of vanadia sites in V-silicalite, vanadia-silica cogel, and silica-supported vanadia catalysts: X-ray powder diffraction, Raman spectroscopy, Solid-state51V NMR, Temperature-programmed reduction, and methanol oxidation studies. J Catal 178:640–648CrossRefGoogle Scholar
- 22.United States Environmental Protection Agency (1994) Waste analysis at facilities that generate, treat, store and dispose of hazard waste. A guidance manual US-EPA. https://www.epa.gov
- 26.CIE S014-4/E:2007 (ISO11664-4 :2008) Colorimetry—part 4: CIE 1976 L*a*b* color spaces. Standard by Commission Internationale de l’EclairageGoogle Scholar
- 27.CIE S014-2/E:2006/ISO11664-2 :2007(E) CIE Standard Illuminants for Colorimetry. Standard by Commission Internationale de l’EclairageGoogle Scholar
- 28.CIE S014-6/E:2013 Colorimetry—part 6: CIEDE 2000 color—difference formula. Standard by Commission Internationale de l’EclairageGoogle Scholar
- 29.ASTM D7085-04 (2010)e1 Standard Guide for Determination of Chemical Elements in Fluid Catalytic Cracking Catalysts by X-ray Fluorescence Spectrometry (XRF)Google Scholar
- 30.Vahl JM, Converse JE (1980) Ripper procedure for determining sulfur dioxide in wine: collaborative study. J Assoc Off Anal Chem 63:194–199Google Scholar