Continuous Fixed-bed Reactor Research Articles

Hydrogenation of methanol to olefins over highly stable ruthenium oxide protonated fibrous ZSM5 catalyst

Olefins are known as a very decisive starting material for the production of particular polymer products. High demand of olefins as well as increasing of crude oil price make the production of olefins product became crucial issue. Catalytic methanol to olefins offered an alternative route in order to obtain olefins products. The protonated fibrous silica ZSM5 (HFZSM5) was synthesized by microwave assisted hydrothermal method and followed by impregnation of 0.5% ruthenium oxide (RuO2) metal onto the HFZSM5 catalyst (RuO2/HFZSM5). The catalysts were characterized using FESEM, TEM, nitrogen physisorption and pyridine adsorbed FTIR. FESEM and TEM results revealed the spherical morphology with dendrimeric silica fibers of HFZSM5 catalyst. Based on nitrogen physisorption result, slightly increase in surface area was observed after the addition of RuO2 onto the HFZSM5 catalyst surface. Obviously, the introduction of ruthenium metal has increased both Lewis and Brønsted acidity significantly, as observed by pyridine FTIR results. The catalytic methanol to olefin reaction was conducted within 473-673K at atmospheric pressure using continuous fixed bed reactor. The RuO2/HFZSM5 resulted in higher catalytic activity and performance which produced 93.92% olefin yields compared to HFZSM5 catalyst which obtained 88.60% olefin product.

Structure and Activity of Ni2P/Desilicated Zeolite β Catalysts for Hydrocracking of Pyrolysis Fuel Oil into Benzene, Toluene, and Xylene

The effects of desilication (DS) of the zeolite β on the hydrocracking of polycyclic aromatics were investigated using the Ni2P/β catalysts. The Ni2P/β catalysts were obtained by the temperature-programmed reduction (TPR) method, and the physical and chemical properties were examined by N2 physisorption, X-ray diffraction (XRD), 27Al magic angle spinning–nuclear magnetic resonance (27Al MAS NMR), extended X-ray absorption fine structure (EXAFS), isopropyl amine (IPA) and NH3 temperature-programmed desorption (TPD), CO uptake, and thermogravimetric analysis (TGA). The catalytic activity was examined at 653 K and 6.0 MPa in a continuous fixed bed reactor for the hydrocracking (HCK) of model compounds of 1-methylnaphthalene (1-MN) and phenanthrene or a real feedstock of pyrolysis fuel oil (PFO). Overall, the Ni2P/DS-β was observed as more active and stable in the hydrocracking of polycyclic aromatics than the Ni2P/β catalyst. In addition, the Ni2P/β suffered from the coke formation, while the Ni2P/DS-β maintained the catalytic stability, particularly in the presence of large polycyclic hydrocarbons in the feed.

Aromatization of Heavy Naphtha using Modified Zeolite Supported Catalyst

Growing population has increased the dependency toward sustainable energy sources. Research industries have groomed their facilities to find alternative sources of energy. Heavy naphtha can be converted to value added fuel such as gasoline via catalytic conversion. Modified zeolite supported catalyst was employed for aromatization of heavy naphtha to gasoline like liquid. The catalyst was impregnated with 3 wt.% Fe via wet impregnation method. The catalysts prepared were send for characterization using BET, FESEM-EDX and TPD. Catalytic activity was performed at 430-480 °C, LHSV 1 hr-1 and 14 bar in a fixed-bed continuous reactor. The result revealed that the by adding Fe onto the zeolite supported catalyst provides slight improvement of yield.

Aldol Condensation of Cyclohexanone and Furfural in Fixed-Bed Reactor

Aldol condensation reaction is usually catalysed using homogeneous catalysts. However, the heterogeneous catalysis offers interesting advantages and the possibility of cleaner biofuels production. Nowadays, one of the most used kinds of heterogeneous catalysts are hydrotalcites, which belong to a group of layered double hydroxides. This paper describes the aldol condensation of cyclohexanone (CH) and furfural (F) using Mg/Al mixed oxides and rehydrated mixed oxides in order to compare the catalyst activity after calcination and rehydration, as well as the possibility of its regeneration. The catalysts were synthesized by calcination and subsequent rehydration of the laboratory-prepared and commercial hydrotalcites, with Mg:Al molar ratio of 3:1. Their structural and chemical properties were determined by several analytical methods (inductively coupled plasma analysis (ICP), X-ray diffraction (XRD), diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), specific surface area (BET), thermogravimetric analysis (TGA), temperature programmed desorption (TPD)). F-CH aldol condensation was performed in a continuous fixed-bed reactor at 80 °C, CH:F = 5:1, WHSV 2 h−1. The rehydrated laboratory-prepared catalysts showed a 100% furfural conversion for more than 55 h, in contrast to the calcined ones (only 24 h). The yield of condensation products FCH and F2CH was up to 68% and 10%, respectively. Obtained results suggest that Mg/Al mixed oxides-based heterogeneous catalyst is suitable for use in the aldol condensation reaction of furfural and cyclohexanone in a fixed-bed reactor, which is an interesting alternative way to obtain biofuels from renewable sources.

Application of glycerol as carbon source for continuous drinking water denitrification using microorganism from natural biomass

The contamination of water resources by nitrate is a global problem. Indeed, traditional treatment technologies are not able to remove this ion from water. Alternatively, biological denitrification is a useful technique for natural water nitrate removal. This study aimed to evaluate the use of glycerol as a carbon source for drinking water nitrate removal via denitrification in a reactor using microorganisms from natural biomass. The experiment was carried out in a continuous fixed bed reactor using immobilised microorganisms from the vegetal Phyllostachys aurea. The tests were started in batch mode to provide cells growth and further immobilisation on the support. Then, the treatment experiments were accomplished in an up-flow continuous reactor. Ethanol was used as the primary carbon source, and it was gradually replaced by glycerol. The C:N (carbon to nitrogen) ratio and the hydraulic residence time (HRT) were evaluated. It was possible to remove 98.14% of nitrate using a C:N ratio and HRT of 3:1 and 1.51 days, respectively. The results have demonstrated that glycerol is a potential carbon source for denitrification in a continuous reactor using immobilised cells from natural biomass.

Life-cycle sustainability of biomass-derived sorbitol: Proposing technological alternatives for improving the environmental profile of a bio-refinery platform molecule

Improving the environmental performance of the industrial processes for the production of biomass-derived platform molecules is nowadays mandatory to achieve real sustainable bio-refineries. In this work, the sorbitol production starting from corn starch has been evaluated using a cradle-to-gate life cycle assessment (LCA) approach. The objective is figuring out the most impacting operations from an energy and environmental point of view and proposing ways for improving them. Two different alternatives for the production of the starting glucose, enzymatic and acid hydrolysis of corn starch, were studied for the first step. In a second stage, a plant for glucose hydrogenation based on a continuous fixed-bed reactor loaded with Raney nickel has also been considered. Finally, the different stages were integrated into a global process to quantify total environmental impacts. All the stages were implemented in Aspen Plus V10 for variables calculation to get the necessary information for process life cycle inventory. Results revealed that the acid hydrolysis is a better alternative for glucose production, mainly due to its lower energy requirements in comparison with the enzymatic pathway. In the second step, the hydrogenation of glucose, the purification of sorbitol and the compression of hydrogen provided important environmental impacts because of their high consumption of both electricity and heat. Analysis of the integrated process evidence that glucose involves an important relative contribution, higher than 60%, to all of the environmental impact categories. Interestingly, including biogenic carbon for calculations makes that CO2 fixed during corn cultivation almost compensates the emissions of the rest of the process steps, highlighting the importance of using autotrophic biomass as raw materials. Finally, based on these LCA results, technological alternatives for improving sorbitol environmental performance have been proposed and detailed.

Optimization of the process conditions for minimizing the deactivation in the furfural-cyclopentanone aldol condensation in a continuous reactor

This work demonstrates the key role of salts (both anions and alkaline cations) in the activity and stability of Mg-Zr mixed oxide as catalyst for the furfural-cyclopentanone aldol condensation in a continuous fixed bed reactor. Reactants oligomers are shown to cause active sites blockage, controlling the reaction conditions being required to maximize the selectivity for the first condensation adduct.The best results were obtained at pH = 8, using KHCO3 for fixing this pH. At these conditions, 75 % and 14 % of C10 and C15 yields were observed at 8 h on stream, whereas experiments performed at the other conditions show almost total deactivation. This good performance (performance and stability) is explained by a synergistic effect of two phenomena: a good buffering activity of the anion, and the ion exchange involving Na and K, which leads to the stabilization of the basic sites.

Graphene as efficient and robust catalysts for catalytic wet peroxide oxidation of phenol in a continuous fixed-bed reactor

Monolayer graphene film (Gr) as a metal-free catalyst was synthesized on the paper-like sintered stainless steel fibers (PSSF) with three-dimensional net structure by chemical vapor deposition (CVD) technique. The prepared PSSF-Gr was characterized by SEM, EDS, XRD, AFM, TEM, and Raman spectroscopy. Then, the optimum reaction conditions for catalytic wet peroxide oxidation (CWPO) of phenol in a continuous reactor using PSSF-Gr catalysts were explored by analyzing the effects of reaction temperature, feed flow rate, and catalyst bed height on catalytic performance. Moreover, the long-term stability of PSSF-Gr catalyst was investigated and demonstrated complete phenol oxidation and dramatic TOC removal (values ranging between 80.7% and 91.0%) after continuously operating for 72 h under optimum condition. Finally, a reasonable reaction mechanism for CWPO of phenol was proposed by analyzing the HPLC results and evolution of aromatic intermediates content. From these results, seldom toxic aromatic intermediates were observed on account of the production of short-chain organic acids by opening of aromatic ring, which subsequently mineralized to CO2 and H2O. The simple preparation method, unique structure, extraordinary catalytic activity and stability of the graphene-based material would provide a new potential catalyst for environmental catalysis.

Alumina-supported MoNx, MoCx and MoPx catalysts for the hydrotreatment of rapeseed oil

The catalytic activity of molybdenum carbide (MoCx), nitride (MoNx), and phosphide (MoPx) was compared in the hydrotreatment of rapeseed oil performed in a continuous fixed bed reactor at 350–390 °C, 5.5 MPa and various Weight Hourly Space Velocities (WHSV). The deoxygenation activity was in the following order: MoCx > MoNx >> MoPx. In the case of MoCx, the temperature increase resulted in a decrease of the deoxygenation activity due to the competitive hydrocracking. Wherein, MoNx showed the highest tendency to hydrocracking and very strong effect of WHSV at 350 °C, which then became less significant at higher reaction temperatures. While MoPx activity was strongly influenced by the mass transfer limitations.

Biomass-derived CO2 rich syngas conversion to higher hydrocarbon via Fischer-Tropsch process over Fe–Co bimetallic catalyst

Biomass-derived syngas (CO2 + CO + H2) has emerged as a potential non-fossil fuel source to yield transportation fuel via Fischer Tropsch Synthesis (FTS) reaction. Thus, the present study demonstrates the conversion of CO2 containing syngas into fuel range hydrocarbon via Fischer Tropsch Synthesis over Fe–Co bimetallic catalyst. The experimental tests were carried out in a fixed bed continuous reactor to investigate the effect of CO2 on CO/CO2 conversion. Accordingly, obtained data were validated by FTS kinetic model for a plug flow reactor. It was found that the unique combination of Fe and Co bimetallic catalyst facilitates both FTS and water gas shift (WGS) reaction simultaneously that helps to convert CO2 along with CO. It was also observed that the presence of iron in the catalyst helps in conversion of CO2 into hydrocarbons, only when a particular concentration of CO2 in syngas is reached, i.e., critical ratio RC (CO2/CO + CO2) due to the occurrence of reverse water gas reaction (RWGS) which varies with the temperature and the feed gas composition (H2/CO/CO2 molar ratio). At 240 °C and hydrogen deficient condition, the critical ratio was measured to be 0.74 whereas for hydrogen balanced condition, it was measured 0.6. The kinetic model developed in the present study predicted trends for % CO conversion, % carbon conversion, and % CO2 conversion which is applicable for a wide range of critical ratio RC (CO2/(CO + CO2) = 0 to 1). The model also predicted that a positive conversion of CO2 could be achieved at lower CO2 concentration by increasing the reaction temperature. At 260 °C and 280 °C, the value of Rc were 0.31 and 0.18 were measured.

Synthesis of graphene with different layers on paper-like sintered stainless steel fibers and its application as a metal-free catalyst for catalytic wet peroxide oxidation of phenol

Different layers of graphene (Gr) films are prepared on the paper-like sintered stainless steel fibers (PSSF) support with three-dimensional structure by CVD method. The effects of acetylene flow rate, deposition time, and deposition temperature on the properties of PSSF-Gr are investigated by EDS, AFM, SEM, TEM, and Raman spectroscopy, respectively. Then, the catalytic performances of PSSF-Gr with different layers of Gr films as metal-free catalysts for catalytic wet peroxide oxidation (CWPO) of phenol are assessed in the continuous fixed-bed reactor. The catalytic results demonstrate that the PSSF-Gr catalyst with single layer graphene film achieves the best catalytic performance (phenol and TOC removal efficiency reach 99% and 73%, respectively) after continuously operating for 6 h. Under the treatment of the PSSF-Gr catalyst with single-layer graphene, total phenol oxidation and excellent TOC removal (maintain about 71%) have been achieved for the long-term operation (38 h). Moreover, the phenol conversion of blank experiment (without catalyst) and PSSF are around 40%, which are caused by thermal degradation and thus, the excellent catalytic activity of PSSF-Gr is ascribed to graphene. Like other Fenton’s catalysts, the catalytic mechanism of PSSF-Gr catalyst in phenol degradation is also a ·OH mechanism.

Experimental investigations on olefin to paraffin ratio in Fischer-Tropsch products using syngas of low Ribblet ratio

Biosyngas generated from gasification of agricultural and forest wastes can be utilized as feed in a Fischer-Tropsch reaction after raising its Ribblet ratio (H2/(2CO+3CO2)) to unity through energy-intense steps of Water-Gas-Shift reaction and carbon dioxide removal. The direct utilization of raw biosyngas with low Ribblet ratio is a sustainable approach for the production of carbon-neutral synthetic fuel from waste biomass. This work investigates the olefin to paraffin ratios in C2 -C3 range of hydrocarbons among the Fischer-Tropsch products under different process conditions. A deviation from the classical Anderson-Schulz-Flory (ASF) distribution for enhancing product selectivity towards fuel range hydrocarbons, is possible due to the higher activity of C2 olefins in various secondary reactions. The investigations in this study also indicate the presence of equilibrium in the ratio of bulk C3 (olefin + paraffin) / C2 (olefin + paraffin) irrespective of reaction feed composition. A laboratory prepared 0.5Fe/ComesoHZSM-5 catalyst was used with model biosyngas of 0.6, 0.4, and 0.2 Ribblet ratios as feed and the reaction were performed in a continuous fixed-bed reactor in the temperature range of 220–260 °C and space velocities of 1800-3400 mLh−1gcat−1. The experimental results show a similar trend in carbon monoxide conversion per gram of catalyst for Ribblet ratios of 0.6 and 0.4. The olefin to paraffin ratio in lower hydrocarbon range (n ≤ 5) for various carbon monoxide conversions is used as an indicator of chain growth efficiency in Fischer-Tropsch synthesis.

Hydrodeoxygenation of raw bio-oil towards platform chemicals over FeMoP/zeolite catalysts

The hydrodeoxygenation of raw bio-oil was investigated in a continuous fixed bed reactor over a series of FeMoP/zeolite catalysts, pursuing a maximized and stable production of phenolics and aromatics. After 5 h of reaction, the catalysts reach a pseudosteady activity state. The FeMoP/HZSM-5 catalyst yields the highest amount of carbon products (53.5 wt%) with the highest selectivity towards aromatics (13.6 wt%, dry basis) and phenolics (12.2 wt%), due to the synergy between the weak acidity of the FeMoP and the mild acidity of the HZSM-5 zeolite, which minimizes dehydration and gasification. The MFI framework allows the sweeping of coke precursors.

Effects of Ion Exchange Process on Catalyst Activity and Plasma-Assisted Reactor Toward Cracking of Palm Oil into Biofuels

Biofuels can be produced through a conventional catalytic cracking system and/or a hybrid catalytic-plasma cracking system. This paper was focused on studying effect of Na+ ion exchange to HY-Zeolite catalyst on catalyst performance to convert palm oil into biofuels over a conventional continuous fixed bed catalytic cracking reactor and comparing the catalytic cracking performance when carried out in a continuous hybrid catalytic-plasma reactor. The catalysts were characterized by X-ray Diffraction (XRD) and Bruneuer-Emmet-Teller (BET) surface area methods. The biofuels product were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS) to determine the hydrocarbons composition of biofuels product. From the results, ion exchange process of Na+ into HY-Zeolite catalyst decreases the catalyst activity due to decreasing the number of active sites caused by blocking of Na+ ion. The selectivity to gasoline ranges achieved 34.25% with 99.11% total conversion when using HY catalyst over conventional continuous fixed bed reactor system. Unfortunately, the selectivity to gasoline ranges decreased to 13.96% and the total conversion decrease slightly to 98.06% when using NaY-Zeolite catalyst. As comparison when the cracking reaction was carried out in a hybrid catalytic-plasma reactor using a spent residual catalytic cracking (RCC) catalyst, the high energetics electron from plasma can improve the reactor performance, where the conversion and yield were increased and the selectivity to lower ranges of hydrocarbons was increased. However, the last results were potential to be intensively studied with respect to relation between reactor temperature and plasma-assisted catalytic reactor parameters. Copyright © 2019 BCREC Group. All rights reserved

PdIn Catalysts in a Continuous Fixed Bed Reactor for the Nitrate Removal from Groundwater

Abstract The ground water (GW) is a real sample of water which contains nitrates (81 mg/L), carbonates and sulphates. This sample was treated by catalytic reduction in a bubble column fixed-bed reactor. The reaction conditions were room temperature and atmospheric pressure, and hydrogen was used as reducing agent. A comparison between the catalytic activity of Pd,In/SiO2 and Pd,In/Al2O3 catalysts was performed, giving the latter the best results regarding the nitrate conversion and the former the selectivity to nitrogen. Synthetic water containing nitrates (SW) and the groundwater (GW) with high salinity (81 mg/L nitrates) and humic acid content were treated in these conditions using HCl and CO2 as acidifiers. When the SW was acidified with CO2 at an H2 flow (2.17 mL/min), more than 50 % of conversion was obtained with an ammonia and nitrite concentrations of 0.44 and 0.92 ppm respectively. These results reached the level established by the WHO and the USEPA. However, both Pd,In/SiO2 and Pd,In/Al2O3 catalysts showed evidence of some deactivation process. This deactivation was higher in the GW sample, possibly due to the presence of Ca+2 and Mg+2 cations that precipitate on the active sites, and/or the presence of humic acids. The characterization studies indicated that, after the reaction, the composition of the metal phases was modified, specifically on their surface. As the catalyst activity is related to surface ratio Pd/In, a relative increase in the concentration of Pd decreases the activity and causes changes in the selectivity to N2. Some sintering of the metal particles was also observed to contribute to catalyst deactivation. Nevertheless, promising results were obtained since a high water volume could be treated with a relatively low amount of low metal loading catalysts.

Catalytic Ozonation by Manganese, Iron and Cerium Oxides on γ-Al2O3 Pellets for the Degradation of Organic Pollutants in Continuous Fixed-Bed Reactor

ABSTRACTHeterogeneous catalytic ozonation is an efficient technology for degrading refractory organic pollutants in water. However, most studied heterogeneous catalysts for catalytic ozonation were powders, which were not practically available for continuous fixed-bed reactor in water treatment. In this work, manganese, iron and cerium oxides on γ-Al2O3 pellets were synthesized and used as heterogeneous catalysts for catalytic ozonation in a continuous fixed-bed reactor. Results showed that all the prepared metal oxides on γ-Al2O3 pellets exhibited facilitated catalytic ozonation for degrading refractory contaminates compared with ozonation alone and catalytic ozonation on pure γ-Al2O3 pellets. The cerium oxides supported on γ-Al2O3 pellets (CeO2/γ-Al2O3) performed best catalytic performance with the COD removal efficiency of 64.3% and TOC removal efficiency of 41.7%. Moreover, the catalytic activity was further enhanced by the synergistic effect of the bimetallic oxides on γ-Al2O3 pellets (CeO2-Fe2O3/γ-Al2O3). This study is expected to help to encourage further research and applications in AOPs based on the success of this work in designing heterogeneous catalysts available for continuous fixed-bed reactor.

Renewable hydrogen production via steam reforming of simulated bio-oil over Ni-based catalysts

The production of hydrogen via steam reforming (SR) of simulated bio-oil (glycerol, syringol, n-butanol, m-xylene, m-cresol, and furfural) was investigated over Ni/CeO2-Al2O3 and Me-Ni/CeO2-Al2O3 (Me = Rh, Ru) catalysts. Monometallic (Ni) and bimetallic (Rh-Ni and Ru-Ni) catalysts were prepared by the wetness impregnation technique of the CeO2-Al2O3 support previously synthesized by the surfactant-assisted co-precipitation method. The as-prepared powders were systematically characterized by N2-physisorption, XRD, H2-TPR, and TEM measurements to analyze their structure, morphology, and reducibility properties. Experiments were performed in a continuous fixed-bed reactor at atmospheric pressure, temperature of 800 °C, steam to carbon (S/C) ratio of 5, and WHSV of 21.15 h−1. Then, the temperature was decreased to 700 °C and increased afterwards to 800 °C. After the experiments TPO and TEM analysis were performed on the spent catalysts to check any evidence of catalyst deactivation. The results showed that the incorporation of noble metal (Ru or Rh) promoter positively affected the activity of the Ni/CeO2-Al2O3 catalysts by enhancing the reducibility of Ni2+ species. Ni-based catalyst deactivated under the studied conditions, whereas Ru- and mainly Rh-promoted systems showed increased resistance to carbon deposition by favouring the gasification of adsorbed carbon species. Between all tested catalysts, the Rh-Ni/CeO2-Al2O3 provided the highest H2 yield and coking-resistance in SR of simulated bio-oil.

Benzene Reduction in Reformate Gasoline by Competitive Hydrogenation: Effect of the Preparation Method

AbstractThe hydrogenation of benzene in reformate gasoline was carried out over nickel supported on silica prepared by precipitation‐gel, co‐precipitation, deposition‐precipitation and sol‐gel techniques. The evaluation was investigated in a continuous fixed bed reactor fed by a stream of reformate gasoline at 398–473 K under atmospheric pressure. X‐ray diffraction, Field emission scanning electron microscopy, X‐ray fluorescence, energy dispersive X‐ray spectrometry‐map, H2 chemisorption and N2 adsorption/desorption techniques have been used to characterize the influence of preparation methods. In the present work, the influences of H2/benzene molar ratios and space velocities on catalytic activity were studied by calculating conversion, specific rate during the benzene hydrogenation. The results show that the surface area of supports is not effective on metal dispersion, and it depends upon the preparation method, the content of metal loading, and interaction between metal and supports. Benzene conversion with catalyst prepared by sol‐gel and deposition‐precipitation method was 4–6 times more than that of toluene. The best performance of benzene hydrogenation was achieved with catalyst prepared by deposition‐precipitation method at 448 K. Among the preparation method, deposition‐precipitation was the best method for preparation of nickel catalyst due to the high and homogeneous dispersion of nickel particles.

Efficient Production of Furanic Diether in a Continuous Fixed Bed Reactor

AbstractThe selective conversion of 2,5‐bis(hydroxymethyl)furan (BHMF) to 2,5‐bis(ethoxymethyl)furan (BEMF) was investigated in a fixed bed reactor over several heterogeneous solid acid catalysts, including Amberlyst‐15, ZSM‐5, Mordenite, and a series of hierarchically structured ZSM‐5 zeolites (HSZ). The HSZ catalysts exhibited superior catalytic performance to other three commercial catalysts. The highest yield of BEMF (90.46 %) was obtained over the HSZ‐150 catalyst under the reaction condition of 140 °C, 2.0 MPa of H2, and 0.3 h−1 of WHSV. Moreover, the HSZ‐150 catalyst displayed an extremely good stability in the etherification reaction, maintaining more than 80 % yield of BEMF for about 80 h. The outstanding catalytic performance of the HSZ‐150 catalyst could be ascribed to that the presence of mesopores enhanced the etherification activity by alleviating the diffusion limitation, and the appropriate acidity improved the BEMF selectivity via suppressing the side reactions.

Catalytic Wet Air Oxidation (CWAO) of Phenol in a Fixed Bed Reactor Using Supported Ru and Ru‐Au Catalysts: Effect of Gold and Ce Loading

AbstractCatalysts of Ru and Ru−Au prepared by the wet impregnation and Deposition‐Precipitation methods supported on ZrO2 modified by CeO2(10 and 20 wt%) synthetized by sol‐gel method, in order to study Au and CeO2 addition effect in the catalytic wet air oxidation of phenol, carried out in an automatized continuous fixed‐bed reactor using oxygen as an oxidizing source. Characterizations of the catalysts were made by X‐ray Diffraction (XRD), Specific Surface Area (BET), X‐ray Photoelectron Spectroscopy (XPS), Transmission Electronic Microscopy (TEM), Scanning Electronic Microscopy (SEM), Ultraviolet–visible Spectroscopy (UV‐vis) and Temperature Programmed Desorption of Ammonia (NH3‐TPD). The effect of Au is reflected in the selectivity to CO2 of the catalysts Ru‐ZrO2 and Ru−Au‐ZrO2 with the increase in selectivity from 89 to 95% related to the increase in acidity which increases from 70 to 102 (μmol of NH3/ gCat). Ce loading effect in this case was important to the enhance the CO2 selectivity explained by the formation of Ce4+‐O2−‐M that could favor the oxygen transfer between the catalyst surface and the adsorbed species by a redox mechanism.