Abstract
We report the synthesis of cerium oxide, cobalt oxide, mixed cerium, and cobalt oxides and a Ce–Co/Al2O3 membrane, which are employed as catalysts for the catalytic wet oxidation (CWO) reaction process and the removal of formaldehyde from industrial effluents. Formaldehyde is present in numerous waste streams from the chemical industry in a concentration low enough to make its recovery not economically justified but high enough to create an environmental hazard. Common biological degradation methods do not work for formaldehyde, a highly toxic but refractory, low biodegradability substance. The CWO reaction is a recent, promising alternative that also permits much lower temperature and pressure conditions than other oxidation processes, resulting in economic benefits. The CWO reaction employing Ce- and Co-containing catalysts was carried out inside a slurry batch reactor and a membrane reactor. Experimental results are reported. Next, a mixed Ce–Co oxide film was supported on an γ-alumina membrane used in a catalytic membrane reactor to compare formaldehyde removal between both types of systems. Catalytic materials with cerium and with a relatively large amount of cerium favored the transformation of formaldehyde. Cerium was present as cerianite in the catalytic materials, as indicated by X-ray diffraction patterns.
Highlights
The catalytic wet oxidation processes fall within the three-phase reaction categories, which are somewhat difficult to operate and are not in a state of technological readiness for commercial application
It is widely recognized that the technology of catalytic wet air oxidation (CWAO)
In wet air oxidation (WAO) processes, organic pollutants dissolved in water are degraded, either partially through an oxidizing agent in biodegradable products or mineralized into harmless inorganic compounds, such as CO2, H2 O, and inorganic salts, which remain in the liquid phase [1]
Summary
The catalytic wet oxidation processes fall within the three-phase reaction categories, which are somewhat difficult to operate and are not in a state of technological readiness for commercial application. It is widely recognized that the technology of catalytic wet air oxidation (CWAO). In wet air oxidation (WAO) processes, organic pollutants dissolved in water are degraded, either partially through an oxidizing agent in biodegradable products or mineralized into harmless inorganic compounds, such as CO2 , H2 O, and inorganic salts, which remain in the liquid phase [1]. Compared to the WAO process, the presence of a catalyst in CWAO has lower energy requirements [2]; in addition, it has the advantage of reaching a greater oxidation conversion. Wet air oxidation [3] represents an alternative technology to treat water streams with a low concentration of toxic organic compounds.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
