Enhanced Photocatalytic Degradation of p-Nitrophenol and Phenol Red Through Synergistic Effects of a CeO2-TiO2 Nanocomposite
Abstract
2033 10325
Enhanced Photocatalytic Degradation of p-Nitrophenol and Phenol Red Through Synergistic Effects of a CeO2-TiO2 NanocompositeAbstract
Organic compounds are one of the most severe pollutants occurring in the environment. Hence, it is important to remove these compounds from the environment through remediation processes such as photocatalysis. The present study investigated the photocatalytic degradation of p-nitrophenol (NP) and phenol red (PR) using a cerium oxide-titanium oxide nanocomposite (CeO2-TiO2nc) under UV light. CeO2-TiO2nc was synthesized using the co-precipitation method. An X-ray diffraction (XRD) analysis confirmed the phase purity [...] 2033 10325 |
Thermokinetic and Thermodynamic Parameters for Catalytic Pyrolysis of Medium Density Fiber over Ni/Beta Zeoliteby
Abstract
Catalytic pyrolysis is an attractive alternative for converting biomass into energy and chemicals to replace fossil sources. This has encouraged the search for efficient catalysts that can directly remove oxygenated products during pyrolysis, since they are the main problem in the processing and use of the products obtained. The catalytic and non-catalytic pyrolysis of medium density fiber (MDF) over beta zeolite-supported nickel (3 and 5%) was performed using the biomass/catalyst of 1.0/0.2 ratio. The thermokineti [...] 1659 9844 |
The Effect of Oxygen-containing Additives in Feedstock on the Performance of the Catalytic Cracking ProcessAbstract
In this study, we found that adding catalytic cracking feedstock, vacuum gas oil, and naphthenic acids in the amount of 0.005–0.0075% vol. increased the liquid target fractions, i.e., gasoline and light gas oil. The decrease in the yield of hydrocarbon gas at a practically constant degree of conversion of the raw material indicated a small proportion of the reactions of re-cracking of the resulting products. This also indicated the resource-saving nature of the process, allowing a larger amount of gasoline fraction [...] 1084 6973 |
Short Hydroacylation-Based Synthesis of Four Aryl-3-hydroxypropanones, Predictable Biomass-Derived C9 Platform MoleculesAbstract
A two-step protocol for the synthesis of aryl-3-hydroxypropanones, which were regarded as lignin degradation products, was proposed herein. This protocol provided a more rapid and easier access to aryl-3-hydroxypropanones, and aryl-3-hydroxypropanones were expected to be ideal platform molecules for the synthesis of more complex value-added targets. 1428 7766 |
Effect of ZSM-5 Particle Size and Framework Silica-to-Alumina Ratio on Hexane Aromatizationby
Abstract
Parent ZSM-5 and Ga-modified ZSM-5 catalysts with different Si/Al ratios and particle sizes were prepared. The physicochemical properties of the prepared catalysts were investigated by performing X-ray powder diffraction analysis, BET surface area analysis, and NH3-TPD analysis. The performance of the aromatization reaction of the prepared catalysts was evaluated with 1-hexane as a model compound. The zeolite catalysts with a low SiO2/Al2O3 ratio possessed better activity than those with a high SiO2/Al2O3 ratio. Ga [...] 1859 13578 |
Kinetic Modeling of the Esterification of Oleic Acid and Methanol in Conventional and Adsorptive Reaction SystemsAbstract
Biodiesel is derived from renewable vegetable or animal sources and is either used as a standalone fuel or blended with oil-based diesel. The kinetic mechanism of the esterification of oleic acid was investigated in a conventional batch reactor and a batch reactor coupled to a water adsorption system. The esterification was performed with oleic acid and methanol at different temperatures (70 to 110 °C) and alcohol-to-oleic acid molar ratios (3:1 to 9:1), using sulfuric acid as a catalyst. A kinetic model was constr [...] 3673 19161 |
Perovskite Solar Cells: Assessment of the Materials, Efficiency, and Stabilityby
Abstract
Solar cells based on organic-inorganic lead halide perovskites are popular in the photovoltaic community due to their high efficiency, low cost, and solution processability. Understanding the fundamentals of metal halide perovskite and its interfaces is extremely important for achieving high-quality materials and developing efficient devices using these materials with the necessary properties. Various methodologies have been used to evaluate the excellent optoelectronic properties, efficiency, and stability of PSCs [...] 4190 31897 |
3D Printed Polylactic Acid (PLA) Well Plates for Enzyme Inhibition Studies: The Case of Pancreatic Lipaseby
Abstract
3D printed PLA has already been demonstrated for several biotechnological applications, including enzymes immobilization. The prerequisites for an efficient screening assay include using small volumes of reagents, low cost, and rapid screening of large numbers of compounds and extracts. Hence, assays based on microtiter plates are predominant. Thus, designing and fabricating scaffolds on a similar scale, which could serve as immobilization carriers, and their recruitment in inhibitors screening studies is of great [...] 1248 8439 |
Catalytic Co-gasification of Lignites Blended with a Forest Residue under the Carbon Dioxide Streamby
Abstract
The present study investigated the co-gasification of two different lignites blended with the forest residue collected from the land restoration activity sites of open-pit mines located in the region of the Ptolemais basin in North Greece performed under the carbon dioxide stream. All samples were devolatilized in a fixed bed unit prior to the gasification evaluations. The gasification evaluations were performed using a thermal analysis system (TG/DTG) operated at temperatures of up to 1000 °C. The reactivity, [...] 1015 5966 |
Effect of Microwave Radiation on the Development of a Porous Aluminum Carrier of the Active Mass of Catalysts in Heterogeneous Catalytic ReactionsAbstract
In this study, we prepared a fine-grained, aluminum-reinforced alumina support matrix of the active mass of catalysts, which showed activity in heterogeneous catalytic reactions stimulated by electromagnetic radiation in the microwave range. The support absorbed microwave radiation of 2.45 GHz. We compared the textural characteristics of samples of Al/Al2O3 supports obtained by conventional heat treatment to those synthesized by heat treatment in a microwave field. We found several advantages of heat treating poten [...] 1414 6898 |
Microbial Cyclodextrin Glycosyltransferases: Sources, Production, and Application in Cyclodextrin SynthesisAbstract
Cyclodextrin glycosyltransferase (CGTase) is a multifunctional enzyme that hydrolyzes the α-glycosidic bond between two sugar molecules and synthesizes cyclodextrins (CDs) and other transglycosylation products. It is a ubiquitously present extracellular enzyme that offers the CGTase-producing organism the sole right onto starch substrates over other microbes. The present review provides a brief account of diversity among CGTase-producing microbes, CGTase production in different heterologous hosts (wherein ext [...] 2956 22526 |
Heterologous Expression, Characterization, and Comparison of Laccases from the White Rot Causing Basidiomycete Cerrena Unicolorby
Abstract
Lignin is the most abundant renewable source of aromatics on earth, and conversion of it to chemicals and fuels is needed to build an economically viable renewable biofuels industry. Biological routes to converting lignin to fuels and chemicals involve depolymerizing lignin using lignin-degrading enzymes that catalyze the breaking of ether and carbon-carbon bonds in the phenolic and non-phenolic subunits of lignin. Laccases are a crucial class of lignin-degrading enzymes and are copper-containing enzymes capable of [...] 1294 8338 |
Effective Cu/ZnO/Al2O3 Catalyst for Methanol Production: Synthesis, Activation, Catalytic Performance, and Regenerationby
Abstract
A precursor CuO/ZnO/Al2O3 catalyst for methanol synthesis has been prepared at room temperature by introducing a ternary salt solution into the excess of sodium carbonate solution following the reverse co-precipitation method. The catalyst was tested for the synthesis of methanol from synthesis gas. The composition (vol. %) has been presented: CO, 22; CO2, 5.8; N2, 5.5; H2, balance. The methanol productivity was recorded to be 2.7 kg kgcat–1 h–1 at a temperature of 260 °С, a pressure of 3 MPa, and a [...] 3672 34268 |
Design of Heterogeneous Catalysts for the Conversion of Furfural to C5 Derivatives: A Brief Reviewby
Abstract
Technological development made in the field of biomass application allows synthesizing several high-value products, such as furfuraldehyde. Furfural, produced through sequential hydrolysis and dehydration reactions from biomass, is considered a platform molecule and a precursor of several other chemicals and biofuels that are generated following reactions such as hydrogenation, hydrodeoxygenation, and decarboxylation. This review aims to reveal the environmental-friendly mechanisms followed for producing furfural d [...] 1822 13239 |
Removal of As(III) from Water by Cellulase Templated TiO2: A Photocatalytic Oxidation Conjugated Adsorption ProcessAbstract
TiO2 photocatalyst was prepared using cellulase as a biotemplate through a hydrothermal process. The as-prepared catalyst was characterized based on physicochemical techniques and was used to remove As(III) from contaminated water. The cellulase templated TiO2 photocatalyst (TiO2-cellulase) had a large specific surface area, which reached 166.6 m2·g–1. It also had a strong oxidation ability and, thus, behaved well in both photocatalytic oxidation of As(III) and dark adsorption. The pH of the solution h [...] 956 6618 |
Biochemical Characteristics and Healing Activity of Bromelia laciniosa Leaf Proteaseby
Abstract
Macambira plant (Bromelia laciniosa Mart. Ex Shult. & Schult. f.) is a species belonging to the family Bromeliaceae, which is distributed widely in the hinterlands of northeastern Brazil, from Bahia to Piauí states. The plants of this species contain an enzyme complex named bromelain, which has great potential for therapeutic applications. In the present study, bromelain derived from Bromelia laciniosa leaves was assessed for its thermodynamic properties and in vitro cytotoxic and healing activities. Bro [...] 1313 11141 |
Fischer-Tropsch Synthesis on Co/SBA-15 Catalyst: Characterization and Oligomerization Modelingby
Abstract
In this study, we investigated the oligomerization mechanism of the Fischer-Tropsch synthesis catalyzed by a cobalt-based catalyst supported by SBA-15. The Co/SBA-15 catalyst contained 20% w/w of cobalt. It was prepared by the wet impregnation method and characterized by X-ray diffraction (XRD), N2 adsorption-desorption, temperature-programmed reduction (TPR), and scanning electron microscopy coupled to X-ray energy dispersion spectroscopy (SEM-EDS). The FT synthesis was conducted in a slurry bed reactor operating [...] 1427 8256 |
Degradation of Amido Black Dye Using Ultra-Violet Light Catalyzed by Iron Oxide Nanoparticles: Kinetics and Mechanism of Degradationby
Abstract
In this study, we investigated the degradation of amido black dye in an aqueous solution using ultra-violet (UV) light catalyzed by iron oxide nanoparticles (nano-Fe). The nano-Fe was synthesized by sodium borohydride reduction of ferric chloride solution and was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray fluorescence spectrophotometry (XRF). The SEM of the nano-Fe showed regular spherical particles, the XRD examination showed a weak and broad peak at Fe (1 1 0), and the [...] 1295 8407 |
Hydrocracking of Di-and Triaromatic Hydrocarbons to Monoaromatics over Mixed Bi-functional CatalystsAbstract
In this study, we present selective hydrocracking of poly (di and tri) aromatic compounds to monoaromatics, such as benzene, toluene, and xylenes (BTX), over a mixture of Pt/Al2O3 and Y zeolites. The polyaromatic compounds feed is a combined simulated model feed, which is similar to light cycle oil (LCO) in composition. The feed is processed in a fixed bed reactor over a catalyst mixture: in the first step, selective hydrogenation of di and tri-aromatic compounds occurs in the presence of Pt/Al2O3 catalyst, followe [...] 1818 11072 |
Homogeneous {Ti2Ni} Heterotrinuclear Catalyst for Ethylene Polymerization and Copolymerizationby
Abstract
We synthesized and spectroscopically characterized a new heterotrimetallic {Ti2Ni} ethylene (co)polymerization precatalyst containing one (α-diimine)NiBr2 and two (phenoxy-imine)TiCl4 scaffolds. Its calculated structure was investigated at the DFT B3LYP/LACVP** level. Our calculations showed that the titanium(IV) centers were in a slightly distorted trigonal bipyramidal environment, and the average Ti···Ni distance was 8.76 Å. The precatalyst was used for synthesizing polyethylene a [...] 1272 10333 |
Zeolite-Containing Catalysts in Alkylation ProcessesAbstract
This article provides an overview of zeolite-containing catalysts used in the alkylation of benzene and toluene with olefins, isobutane with butenes and butane-butene fractions, gasoline and oil fractions with olefins, propane-propylene, and butane-butylene fractions of catalytic cracking. Zeolites have various types of structures, including BEA, MFI, MWW, FAU, etc., which differ in pore size and the number and location of the channels. High-silica zeolites have a large pore volume, high acidity, good hydrothermal [...] 4077 21737 |
Co2+ Doping and Molecular Adsorption Behavior of Anatase TiO2 (001) Crystal PlaneAbstract
TiO2 (001) crystal plane exhibits molecular adsorption and photocatalytic activity. The loading capacity of reactive oxygen species present on crystal planes helps in the significant improvement of catalytic activity. The methods of synthesis and conditions of existence significantly affect the molecular adsorption properties of crystal planes, which in turn affects the ability of the system to load reactive oxygen species. Herein, we report the simulation of the molecular adsorption behavior on the TiO2 (001) usin [...] 1222 8871 |
Dearomatization of the Kerosene Fraction: Kinetic StudiesAbstract
The kinetics of dearomatization of a kerosene fraction processed using a zeolite catalyst (0.9 HZSM-5) at different temperatures (160-200°C), the molar ratio between the aromatic hydrocarbons present in the kerosene fraction and n-decene (1:(0.5-4)), and the reaction time (1-3 h) were studied. Based on the obtained data, a kinetic model for kerosene dearomatization is proposed. It is assumed that the single-center Riedel mechanism is followed. The stage associated with the interaction between n-decene adsorbed on t [...] 1407 8517 |
3D Fe3O4-decorated Nitrogen-doped Graphene Aerogel as a Highly Durable Electrocatalyst for Oxygen Reduction ReactionsAbstract
The rational design of efficient electrocatalysts for oxygen reduction reaction (ORR) is the key to developing fuel cells and metal-air batteries. Carbon-supported iron-based materials, as the most promising electrocatalysts for ORR, have drawn much attention as they are cost-effective and exhibit high activity. In this work, a three-dimensional (3D) Fe3O4-decorated N-doped graphene aerogel (Fe3O4/NGA) catalyst was synthesized following a simple hydrothermal method which was followed by an annealing process. The co [...] 1568 9906 |
Synthesis of a Solid Base Catalyst Formed from Zinc(II) Acetylacetonate and Consisting of MgO Modified with ZnOAbstract
Solid base catalysts consisting of MgO modified with 10 mol% ZnO (ZnO/MgO) were prepared by depositing zinc(II) acetylacetonate (Zn(acac)2) in polar and nonpolar organic solvents on the surface of MgO and Mg(OH)2. The process was followed by thermal decomposition in air at 773 K over a period of 3 h. The activity of MgO modified with Zn(acac)2 for base-catalyzed retroaldol reaction (the decomposition of diacetone alcohol (4-hydroxy-4-methyl-2-pentanone) to acetone) at 299 K was higher than the activity of unmodifie [...] 1112 8980 |
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