Effectively Synthesizing SO4/TiO2 Catalyst and Its Performance for Converting Ethanol into Diethyl Ether (DEE)

This SO4/TiO2 catalyst as a heterogeneous acidic catalyst was synthesized in various concentrations of H2SO4. The activity and selectivity of the SO4/TiO2 catalyst on the dehydration reaction of ethanol to diethyl ether were studied as well. The SO4/TiO2 was prepared from TiO2 powder by wet impregnation method with a various aqueous solution of H2SO4 (1; 2; 3 M H2SO4) and calcination temperature (400, 500, and 600 °C) to obtain a catalyst with optimum acidity. The catalysts were characterized using FTIR, XRD, SEM-EDX, SAA, TGA/DSC, and acidity test gravimetrically with ammonia. The liquid product of DEE was analyzed by gas chromatography (GC) to analyze the selectivity of the catalyst. The catalyst TS-3-400 had the highest activity and selectivity in the dehydration reaction of ethanol to diethyl ether at a temperature of 225 °C, with a conversion of 51.83% and a DEE selectivity of 1.72%.

Activated Carbon Addition Methods on the Pre-impregnation Process of Co-Mo in Y-Zeolite Ultra Stable: A Properties Exploration and Enhancement of Metals Loaded

The amount of loaded Co-Mo metal on the Y-Zeolite Ultra Stable (USY) was increased by the addition of activated carbon in the pre-impregnation process. USY modification was done by adding activated carbon to USY as much as 10 wt%. The process of adding activated carbon is carried out by three methods, i.e., grinding with sucrose binder (ACU1), without sucrose (ACU2), and conducting by ball milling (ACU3). Wet impregnation method was employed to disperse the Co and Mo, sequentially. Composites were characterized using Fourier Transform Infrared (FTIR), X-ray diffraction (XRD), and surface area analyzer (SAA). Metal dispersions were observed by X-ray fluorescence (XRF). The FTIR suggests an interaction between USY and activated car-bon, while the XRD result indicated the none structural transformation of USY zeolite. The SAA analysis showed an increased total pore radius with the activated carbon addition. The XRF confirmed the increasing of total metals dispersion of 6.25% (ACU1); 5.48%(ACU2); 5.18% (ACU3); compare to USY origin with 3.28% metals loaded.

Mesoporous silica from Parangtritis beach sand templated by CTAB as a support of Mo Metal as a catalyst for hydrocracking of waste palm cooking oil into biofuel

In this study, natural source Parangtritis beach sand was extracted into mesoporous silica (MS). Synthesis of mesoporous silica (MS) was carried out at sodium silicate: CTAB ratio of 1:0.5 (w/w). Monometallic catalyst was used to improve the performance of the catalyst. The monometallic used was Mo metal, which was synthesized using the wet impregnation method. Catalysts were characterized using FTIR, XRD, Surface Area Analyzer (SAA), SEM-EDX, and TEM. MS has pore diameters and surface area of 2.62 nm and 897.3 m2/g. Mo/MS has pore diameters, surface area, and Mo metal concentration of 2.46 nm, 593 m2/g, and 4.75 %. Catalytic activity and selectivity were evaluated in hydrocracking of waste palm cooking oil at 500, 550, and 600 oC, and catalyst: waste palm cooking oil ratio of 1:100, 1:200, and 1:300. The best catalyst will be tested for reusability 3 times through the hydrocracking process. Mo/MS produces better liquid products and hydrocarbon compounds than MS. The results of the conversion of liquid products analyzed using GCMS. The yield of liquid products obtained in the hydrocracking of waste palm cooking oil using Mo/MS with the optimum temperature and the weight ratio of catalyst: feed at 550oC and 1: 300 was 66.99 wt.% with consists of hydrocarbon compound as 62.79 wt.%. The yield of liquid products obtained in the hydrocracking waste palm cooking oil using the used Mo/MS catalyst in the last run was 80.26 wt.% with consist of hydrocarbon compound as 74.13 wt.%.

Catalytic Activity Of Cu/η-Al2O3 Catalysts Prepared From Aluminum Scraps In The NH3-SCO and in the NH3-SCR of NO

Copper loaded η-alumina catalysts with different copper contents have been prepared by impregnation/evaporation method. The catalysts were characterized by XRD, FTIR, BET, UV–vis, H2-TPR and evaluated in the selective catalytic reduction of NO by NH3 and in the selective catalytic oxidation of NH3. The characterization techniques showed that the impregnation/evaporation method permits to obtain highly dispersed copper oxide species on the η-alumina surface when low amount of copper is used (1wt. % and 2 wt.%). The wet impregnation method made it possible to reach a well dispersion of the copper species on the surface of the alumina for the low copper contents Cu(1)-Al2O3 and Cu(2)-Al2O3. The latter justifies the similar behavior of Cu(1)-Al2O3) and Cu(2)-Al2O3 in the selective catalytic oxidation of NH3 where these catalysts exhibit a conversion of NH3 to N2 of the order of 100% at T > 500°C.

Photocatalytic degradation of the 2,4-dichlorophenoxyacetic acid herbicide using supported iridium materials

In this work, the effect of the addition of iridium on TiO2 and Nb2O5 supports obtained by wet impregnation method was evaluated in the photocatalytic degradation of 2,4-dichlorophenoxiacetic acid under UV irradiation. The synthetized materials were analyzed by different techniques in order to determinate their physicochemical properties. In general, it was observed that the addition of iridium modifies the surface area, band gap energy and it enhances the crystallinity of the materials. Besides, an increase in the photoactivity in the degradation of the herbicide was evidenced using the materials modified. However, the Ir/TiO2 photocatalyst possess the best photocatalytic behavior toward the degradation and possible mineralization of the herbicide. The improved performance of the photocatalyst could be argued by the role of the iridium particles as electron collectors favoring the effective separation of the charge carriers and, as consequence, increasing the degradation of the molecule.

Electrocatalytic Hydrogenation of CO2 to Hydrocarbons on Gold Catalyst in the Presence of Ionic Liquid

This study is aimed to investigate the electro-catalytic activity of Au supported on both CeO2 and activated carbon (AC) to convert CO2 to mixture of C1-C4 hydrocarbons in the presence of ionic liquid (IL) 1-butyl-3-methylimidazolium methylsulfonate. The studied catalyst samples were prepared by using simultaneous wet impregnation method. The sample containing 0.6 % Au showed higher electro-catalytic activity than the sample contained 0.3 % Au. Both, the average Au particles size and the transformation of layered non-uniformed semi-oval structure to flaked tiny circular like-structure were mainly responsible for the higher catalytic activity of 0.6Au-CeO2-AC sample. In addition, the overall electro-catalytic activity depends upon the applied reaction voltage. Overall, the presence of IL, the surface morphology, and average Au particles size had played a key role in the electro-catalytic conversion of CO2 to hydrocarbons.

Nickel Supported Modified Zirconia Catalysts for CO2 Methanation in DBD Plasma Catalytic Hybrid Process

The methanation reaction has recently received considerable attention as a perspective CO2 utilization technology leading to the formation of renewable natural gas methane. This reaction is favorable at low temperature, but it is hindered of slow kinetic rates, whereas below a temperature of 270°C, the CO2 conversion is practically 0, and at higher temperatures, 350-400°C, the co-existence of secondary reactions favors the formation of CO. This is the reason why new catalysts and process conditions are continuously being investigated to maximize the methane selectivity, preferably at low reaction temperatures and at atmospheric pressure. Thus, this work is focused on the use of a heterogeneous catalyst Ni/ Zirconia supports modified by rare earth metals such as Lanthanum, tungsten and Yttrium combined to a Dielectric Barrier Discharge plasma. Three catalysts were prepared by a conventional wet impregnation method, using 15 wt% of Ni loading over zirconia supports modified with different promoters. To better define the physical, textural and chemical properties, the catalysts were characterized by the means of BET, XRD, H2-TPR, CO2-TPD. The influence of basicity, Ni crystallite size and the Ni-support interaction on the catalytic activity was clearly evidenced.

Hydrotreatment of Cellulose-Derived Bio-Oil Using Copper and/or Zinc Catalysts Supported on Mesoporous Silica-Alumina Synthesized from Lapindo Mud and Catfish Bone

Catalysts comprising copper and/or zinc supported on mesoporous silica-alumina (MSA) with a high Si/Al ratio were prepared by wet impregnation method. This study investigated the preparation, characterization, and catalytic application of the prepared catalysts for hydrotreatment cellulose-derived bio-oil. The wet impregnation was performed by directly dispersing Cu(NO3)2·3H2O and/or Zn(NO3)2·4H2O aqueous solution into MSA, followed by calcination and reduction under H2 gas stream. The acidity test revealed that metal addition on MSA support increases the acidity of catalysts. During hydrotreatment of cellulose-derived bio-oil CuZn/MSA with total acidity, copper loading, zinc loading, and specific surface area of 24.86 mmol g–1, 5.23 wt.%, 3.15 wt.%, and 170.77 m2 g–1, respectively, exhibited the best performance compared to other prepared catalysts with 90.49 wt.% conversion of liquid product.

Ni/x%Nb2O5/Al2O3 Catalysts Prepared via Coprecipitation-Wet Impregnation Method for Methane Steam Reforming

Background: Hydrogen has been considered the energy source of the future and one of the processes for its production is the methane steam reforming. The catalyst used industrially is Ni/Al2O3 and the addition of promoter oxides can be an alternative to improve the performance of this catalyst, which suffers from coke formation and sintering. Objective: Evaluate the role of niobia on catalytic activity and stability. Methods: Ni/x%Nb2O5/Al2O3 (x = 5, 10 and 20) catalysts were synthesized via coprecipitation-wet impregnation method and characterized by X-ray fluorescence (XRF), N2 adsorption-desorption, X-ray diffraction (XRD), temperature- programmed reduction (TPR), temperature-programmed desorption of ammonia (TPD-NH3), etc. Finally, the catalysts were tested for methane steam reforming reaction. Results: All niobia-doped catalysts presented similar values of methane conversion and when comparing with Ni-Al, the addition of niobia slightly improved the methane conversion. In the stability test at 800oC, all doped and non-doped catalysts did not deactivate during the 24 h of reaction. Conclusion: The addition of 10 and 20 wt.% of niobia had a significant promoter effect over Ni/Al2O3 catalyst in terms of activity and stability at 800 oC and the sample with 20 wt.% of niobia presented lower coke formation.