Download or read book Catalytic Wet Oxidation of Organic Rich Aqueous Fraction Derived from Biomass Thermochemical Processing with Novel Char Catalysts in Microscale Based Reactors written by Iva Jovanovic Tews and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Development of alternative fuel refineries, in order to improve global sustainability through increased biofuel production, has been increasingly supported by both government and private companies. Thermochemical processes such as hydrothermal liquefaction (HTL) and pyrolysis are leading technologies in this area. However, characterization, treatment, and reuse of aqueous by-products produced by such processes have received little attention. This dissertation is focused on aqueous phase characterization and catalytic advanced oxidation processing in novel microscale reactors. Novel char catalysts and improved process design were developed for efficient removal of organic contaminants. Small acids, cyclic pentenes, and carboxylic compounds such as phenol were initially identified. Model compounds were chosen based on these findings, and catalytic wet oxidation (CWO) processes in batch reactors conducted, in order to obtain reaction rate kinetics. The mechanism of compound oxidation was developed and shown through DFT analysis to be a production of hydroxyl free radicals (OH0́) in the presence of an oxidant and the N-doped char catalyst. The OH0́ free radicals readily react with the dissolved organic compound, which was further confirmed with a FeO-N-doped char catalysts in a modified Fenton-like reaction system. In order to better develop a treatment processes which could integrate with a biorefinery, all process engineering experiments were conducted in a continuous solid-catalyzed microscale-based reactor utilizing the FeO-N-doped char catalyst. Time scale analysis was used for reactor geometry optimization in an effort to reduce diffusion time. The design led to a parallel plate reactor with channel depth of 500 microns. Thermochemical aqueous phases produced by pilot scale processes were characterized in detailed by extensive analytical methods. Traditional methods of spectroscopic analysis were limited in the ability to identify more complex oligomeric compounds and thus newer methods such as ICR-MS were utilized. The aqueous phases were successfully treated by the novel catalyst in the microreactor with removal of over 70% total organic carbon present at atmospheric pressure and at 90 ℗ʻC. Some aqueous phase samples were more complex in nature however, successful decontamination was achieved. Catalytic wet oxidation processing in microscale-based reactors proves to be a plausible treatment option for process water in biorefineries.
Download or read book Possibilities of Use of Home produced Catalysts for Wet Catalytic Oxidation of Organic Matter in Water written by K.Y Hu and published by . This book was released on 1985 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Technology of Catalytic Oxidations written by Philippe Arpentinier and published by Editions Technip. This book was released on 2001 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume 1 covers the most important technological aspects of the use of molecular oxygen for catalytic oxidation reactions.Volume 2 addresses the safety issues associated with the use of oxygen in catalytic oxidation reactions.Contents Vol. 1: 1. Introduction. 2. Chemical-physical properties of molecular oxygen. 3. Oxygen production technologies. 4. Chemical fundamentals of oxidation reactions. 5. Reactor technologies for multiphase systems. 6. Liquid phase oxidations. 7. Gas phase selective oxidations. 8. Selective oxidation of paraffins. References. Index. Vol. 2: 9. Introduction to safety problems in the chemical industry. 10. Chemical aspects of combustion in the gaseous phase. 11. Homogeneous chemical explosions: autoignition or spontaneous ignition. 12. Deflagration or propagation of flame. 13. Conditions governing flame propagation capability. 14. Detonation in the gaseous phase. 15. Prevention of and protection against explosions. References. Index.
Download or read book Catalytic Wet Oxidation of Organic Impurities in Water with a Nanocasted Mixed Oxide Catalyst of Transition Metals written by Marina Milman and published by . This book was released on 2007 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Catalytic Oxidation of Hydrocarbons written by Karl C. Stein and published by . This book was released on 1963 with total page 1200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Catalysts for Alcohol fuelled Direct Oxidation Fuel Cells written by Zhen-Xing Liang and published by Royal Society of Chemistry. This book was released on 2012 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a state-of-the-art review on recent advances in nanocatalysts and electrocatalysis in DOFCs.
Download or read book The Catalytic Oxidation of Organic Compounds in the Vapor Phase written by Leroy Frank Marek and published by . This book was released on 2013-06 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: Additional Contributors Include Harrison E. Howe, S. C. Lind, Walter A. Schmidt, And Others.
Download or read book The Catalytic Oxidation of Organic Compounds in the Vapor Phase written by Leroy Frank Marek and published by . This book was released on 1932 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Catalytic Oxidation in Organic Synthesis written by K. Muñiz and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Catalytic Wet Oxidation of Organic Wastes Using Platinum Catalysts written by Z. P. G. Masende and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Catalytic Wet Oxidation Over Pillared Clay Catalyst in Packed bed Reactors written by Jing Guo and published by . This book was released on 2005 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Catalytic Oxidation in Organic Synthesis written by Kilian Muñiz and published by Thieme Chemistry. This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of catalytic systems for the oxidation of organic compounds continues to be of great importance. There is an ongoing and increasing demand for methods that are selective, proceed under mild conditions, and adhere to green chemistry principles. "Science of Synthesis: Catalytic Oxidation in Organic Synthesis" includes the latest developments in the field, as well as selective coverage of more well-established methods. Systems based on metal catalysts, organocatalysts, and biomimetic oxidation are covered, and there is a particular focus on asymmetric processes. Scope, limitations, and mechanism of the reactions are discussed and key experimental procedures are included. Typical examples of target synthesis are often provided to show the utility and inspire further applications.
Download or read book Novel Photodeposited Catalysts for Carbon Monoxide Oxidation and Preferential Oxidation of Carbon Monoxide in the Presence of Hydrogen PROX written by Sze Chi Chan and published by ProQuest. This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: It has been shown that gold nanoparticles supported on metal oxides with sizes below 5 nm exhibit unique catalytic properties for CO oxidation, water-gas shift, and epoxidation of propylene. In particular, Au/TiO 2 exhibits CO oxidation activity at temperature as low as 90 K. Recent research reported that silver nanoparticles supported on TiO 2 are similar to Au nanoparticles supported on TiO 2 . Conventional methods for preparing Ag/TiO 2 and Au/TiO 2 supported catalysts include deposition-precipitation, wet impregnation and co-precipitation. Among these methods deposition-precipitation has shown the best results for these reactions due to the narrow size distribution of Ag and Au. The major disadvantage of the deposition-precipitation method is that Au and Ag particle sizes are very sensitive to precursor concentration. Preparation of Au particles less than 5 nm requires a low precursor concentration and low Au loading. In this work, a different approach, photodeposition, was used to prepare Ag and Au nanoparticles supported on TiO 2 . The main shortcoming of photodeposition is that its efficiency is very sensitive to both bulk and surface structural features. However, such problems can be overcome by reducing the size of TiO 2 particles to the nanoscale. Photodeposition of Ag nanoparticles on commercial TiO 2 particles and nanoparticles was performed on microscope grid-supported samples in order to provide direct visualization of the spatial distribution of photoactive sites on sub-micron-scale and nanoscale TiO 2 particle surfaces and to create materials for potential catalytic applications. HRTEM (high-resolution transmission electron microscopy) and HAADF-STEM (high-angle annular dark-field scanning transmission electron microscopy) were used to characterize these materials. The size and spatial distributions of the Ag nanoparticles on the commercial TiO 2 were not uniform; the concentration of Ag was higher on grain boundaries and at the edges of these submicrometer particles. In the case of TiO 2 nanoparticles, the size distribution of the Ag nanoparticles deposited was relatively uniform and independent of irradiation time and photon energy. The amount of Ag deposited on TiO 2 nanoparticles was at least 6 times higher than that on commercial samples for comparable irradiation conditions. Compared to the case of Ag photodeposition, the difference in the amount of Au photodeposited on TiO 2 particles and nanoparticles was even greater, especially at low precursor concentration. Photodeposition on TiO 2 nanoparticles is suggested as a potential method for the preparation of Ag/TiO 2 and Au/TiO 2 catalysts. The high photoreactivity of TiO 2 nanoparticles makes them an ideal material for preparation of supported metal catalysts when highly uniform nanoscale particle size is required. Extending the previous work, the Ag and Au photodeposition on TiO 2 nanoparticles were scaled-up from micro scale to laboratory scale to generate sample powders in sufficient quantity to be utilized in catalytic reactor. Most of the methods published for the preparation of metal-decorated TiO 2 by photodeposition involve suspended particles in a aqueous media. Our approach for the scale-up process was different, and was developed based on the sample preparation for metal photodeposition on microscope grids. A thin film of TiO 2 nanoparticle powders coated on a glass plate was obtained by using a spin-coating technique before metal photodeposition. Several commercial TiO 2 nanoparticles were used in this study, in order to choose appropriate samples for the scale-up experiments. Preliminary studies of the photoreactivity of commercial TiO 2 nanoparticles for Ag photodeposition on a microscope grid were carried out prior to the scale-up process. The effects of Ag photoreduction conditions, in particular the radiation source and the metal precursor solution concentration, on Ag photodeposition were investigated to determine the optimum conditions for the scale-up process. The size and spatial distribution of Ag nanoparticles, as well as the Ag loading on commercial TiO 2 nanoparticles for the scale up process under various conditions were determined using TEM and HAADF-STEM techniques. After the optimal conditions for the scale-up process were established, Ag/TiO 2 and Au/TiO 2 nanoparticles obtained from the scaled-up process were characterized by atomic absorption spectroscopy (AAS), X-ray diffraction (XRD), Xray photoelectron spectroscopy (XPS) and HAADF. In addition, Ag/TiO 2 and Au/TiO 2 nanoparticles were also prepared using traditional deposition-precipitation methods. The catalytic performance of Ag/TiO 2 and Au/TiO 2 nanoparticles prepared using two different methods for CO oxidation and preferential oxidation of CO in the presence of H 2 (PROX) were investigated using a high-throughput reactor. Results obtained from this study showed that the size of Ag particles, Ag loading, as well as preparation method contributed to the difference in activity of Ag/TiO 2 for CO oxidation and PROX. In the case of Au/TiO 2 the difference in activity for CO oxidation and PROX is mainly due to the preparation method and Au loading.
Download or read book Catalytic Processes for Water and Wastewater Treatment written by John Vakros and published by Mdpi AG. This book was released on 2023-04-13 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalytic oxidation or reduction processes are among the most efficient processes for water and wastewater treatment. These include photocatalysis, sulfate and hydroxyl-radical-based advanced oxidation processes. This Special Issue contains the contributions of different research groups and discusses the recent progress and advances in catalytic processes in water and wastewater treatment.
Download or read book New Insights in Selective Oxidation Catalysis Electrocatalysis and Catalysis of Biomass written by Robert K. Grasselli and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heterogeneous Catalytic Oxidation of Organic Compounds in Wastewater written by William Richard Killilea and published by . This book was released on 1974 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Selectivity of Oxidation Reactions Over Catalytic Monoliths written by Daniel Alan Hickman and published by . This book was released on 1992 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt:
