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... Sulfite (SO₃²⁻) activation is one of the most potential sulfate-radical-based advanced oxidation processes, and the catalysts with high efficiency and low-cost are greatly desired. In this study, the cobalt nanoparticles embedded in nitrogen-doped graphite layers (Co@NC), were used to activate SO₃²⁻ for removal of Methyl Orange in aqueous solution. The Co@NC catalysts were synthesized via pyrolysi ...
ammonium nitrogen; carbon; catalysts; chlorides; density functional theory; electrochemistry; iron; oxidation; pollutants; wastewater; China
Abstract:
... Ammonia nitrogen (NH₄⁺-N) is a ubiquitous environmental pollutant, especially in offshore aquaculture systems. Electrochemical oxidation is very promising to remove NH₄⁺-N, but suffers from the use of precious metals anodes. In this work, a robust and cheap electrocatalyst, iron single-atoms distributed in nitrogen-doped carbon (Fe-SAs/N-C), was developed for electrochemical removal of NH₄⁺-N from ...
air; catalysts; catalytic activity; electron paramagnetic resonance spectroscopy; electron transfer; oxygen; ozone; pollution; temperature; China
Abstract:
... In recent years, near surface ozone pollution, has attracted more and more attention, which necessitates the development of high efficient and low cost catalysts. In this work, CuO/Cu₂O heterojunctioned catalyst is fabricated by heating Cu₂O at high temperature, and is adopted as ozone decomposition catalyst. The results show that after Cu₂O is heated at 180°C conversion of ozone increases from 75 ...
acidity; aromatic compounds; catalysts; oxidation; synergism; zeolites; China
Abstract:
... Different zeolites supported Pt catalysts with micro-mesoporous structure were prepared by organic base tetrapropylammonium hydroxide (TPAOH) treatment and their catalytic oxidation activity for various volatile organic compounds (VOCs) were evaluated. The results reveal that the synergistic effect between Pt nanoparticles and surface acid sites plays an important role in VOCs low-temperature remo ...
... As the main contributor of the formation of particulate matter as well as ozone, volatile organic compounds (VOCs) greatly affect human health and the environmental quality. Catalytic combustion/oxidation has been viewed as an efficient, economically feasible and environmentally friendly way for the elimination of VOCs. Supported metal catalyst is the preferred type of catalysts applied for VOCs c ...
... Pt catalysts with nitrogen-doped graphene oxide (GO) as support and CeO₂ as promoter were prepared by impregnation method, and their catalytic oxidation of formaldehyde (HCHO) at room temperature was tested. The Pt-CeO₂/N-rGO (reduced GO) with a mass fraction of 0.7% Pt and 0.8% CeO₂ exhibited an excellent catalytic performance with the 100% conversion of HCHO at room temperature. Physicochemical ...
... Microbial electrosynthesis system (MES) is a promising method that can use carbon dioxide, which is a greenhouse gas, to produce methane which acts as an energy source, without using organic substances. However, this bioelectrical reduction reaction can proceed at a certain high applied voltage when coupled with water oxidation in the anode coated with metallic catalyst. When coupled with the oxid ...
... This paper synthesized a new type of ternary piezoelectric catalyst MoOₓ/ZnS/ZnO (MZZ) by a one-step method. The catalytic degradation of Rhodamine B (RhB) solution (10 μg/g, pH = 7.0) shows that the composite catalyst has excellent piezoelectric catalytic activity under ultrasonic vibration (40 kHz). The piezoelectric degradation rate of the optimal sample reached 0.054 min⁻¹, which was about 2.5 ...
biochar; biomass; carbon dioxide; catalysts; catalytic activity; dyes; electric impedance; electron paramagnetic resonance spectroscopy; electron transfer; hydroxyl radicals; magnetism; pyrolysis; rhodamines; singlet oxygen; sulfates; surface area; China
Abstract:
... Herein, a one-step co-pyrolysis protocol was adopted for the first time to prepare a novel pyrogenic carbon-Cu⁰/Fe₃O₄ heteroatoms (FCBC) in CO₂ ambiance to discern the roles of each component in PDS activation. During co-pyrolysis, CO₂ catalyzed formation of reducing gases by biomass which facilitated reductive transformation of Fe³⁺ and Cu²⁺ to Cu⁰ and Fe₃O₄, respectively. According to the analys ...
Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; azo dyes; catalysts; electron paramagnetic resonance spectroscopy; energy-dispersive X-ray analysis; hot water treatment; hybrids; magnetism; mass spectrometry; pH; pollution; reaction mechanisms; temperature; thermogravimetry; wastewater; China
Abstract:
... Wastewater containing an azo dye Orange G (OG) causes massive environmental pollution, thus it is critical to develop a highly effective, environmental-friendly, and reusable catalyst in peroxymonosulfate (PMS) activation for OG degradation. In this work, we successfully applied a magnetic MnFe₂O₄/α-MnO₂ hybrid fabricated by a simple hydrothermal method for OG removal in water. The characteristics ...
... Ce₁₋ₓZrₓO₂ composite oxides (molar, x = 0-1.0, interval of 0.2) were prepared by a cetyltrimethylammonium bromide-assisted precipitation method. The enhancement of silver-species modification and catalytic mechanism of adsorption-transformation-desorption process were investigated over the Ag-impregnated catalysts for low-temperature selective catalytic oxidation of ammonia (NH₃-SCO). The optimal ...
catalysts; catalytic activity; electrochemistry; nanosheets; oxygen production
Abstract:
... The development of highly-efficient catalysts for oxygen reduction reaction (ORR) or oxygen evolution reaction (OER) is highly crucial for the commercial applications of some novel energy-related devices. Herein, using comprehensive first-principles computations, the potential of a variety of single metal-based catalysts supported by MoSe₂ nanosheet to boost the ORR or OER process was evaluated. T ...
... The present article demonstrates a synthesis of a green, novel and sustainable heterogeneous catalyst comprising 12-tungstophosphoric acid and zeolitic support- MCM-22. Detailed characterization of the catalyst was carried out using various physicochemical techniques and its catalytic activity was explored for the production of butyl levulinate, a potential fuel blend candidate. The comparison wit ...
air; air temperature; algorithms; catalysts; chemical species; diesel engines; diesel fuel; energy; heat exchangers; prediction; torque
Abstract:
... In current investigation, one dimensional gas dynamic and chemical species prediction are simulated according to diesel engine with air cooler and catalyst. The results of engine cycle modeling are then verified with experimental data and the robust validation is obtained. The key parameters of air/fuel ratio, compression ratio, swirl number, coolant temperature, and air temperature of the heat ex ...
... Nitrophenols(NPs) are highly toxic compounds that occur in various industrial effluents. Herein, we investigated Cu nanoparticle-loaded cellulose nanofibril (CNF/PEI-Cu) aerogels as a catalyst for degrading 4-nitrophenol (4NP) in the wastewater. Non-noble metal based low-cost catalyst material and easily scalable preparation method make CNF/PEI-Cu aerogel as an appropriate catalyst for practical a ...
... In recent years, the development of low-cost and reusable green catalysts to reduce the organic pollutant of 4-nitrophenol (4-NP) into the utilizable intermediate of 4-aminophenol (4-AP) had attracted more and more attention. Herein, we reported a facile strategy to synthesize 3D N-doped graphene/bismuth (NGR/Bi) composites with efficient catalytic properties for 4-NP reduction. TGA exhibited NGR/ ...
... With the increasing energy and environmental crisis, exploring convenient and general strategies for constructing of highly active, stable, and cost-effective bifunctional electrocatalysts for overall water splitting are exceedingly desirable yet still challenging. Herein, 3D hierarchical mesoporous cobalt phosphide embedded N-doped carbon nanoflowers (CoP@NCNFs) are successfully constructed with ...
... Three-dimensional (3D) printing technology has received remarkable attention in manufacturing catalysts with tailored shapes and high precision, particularly facilitating catalyst recovery, maximizing heat/mass transfer, as well as enhancing catalytic performance. Herein, an engineered recombinant Escherichia coli strain (denoted as e-E. coli) with overexpressing metallothionein (a metal-binding p ...
carbon; catalysts; combustion; foams; fuel cells; hydrogen; hydrogen production; mathematical models; methanol; nickel; process design; reaction mechanisms; steam; temperature
Abstract:
... To decrease the temperature difference per unit temperature (ΔTA) of an autothermal methanol steam reforming (ATMSR) microreactor for hydrogen production (HP) and enhance its long-term HP performance for supplying long-term stable hydrogen source for fuel cell vehicles, a three-dimensional (3D)-printed regular-porous structure with multiple microchannels is developed as combustion reaction support ...
Miriam González-Castaño; Francisco Baena-Moreno; Juan Carlos Navarro de Miguel; Kamal U.M. Miah; Fátima Arroyo-Torralvo; Ralf Ossenbrink; Jose Antonio Odriozola; Walther Benzinger; Andreas Hensel; Achim Wenka; Harvey Arellano-García
administrative management; carbon dioxide; catalysts; catalytic activity; energy conversion; experimental design; geometry; heat transfer; hydrogen; mathematical models; methane production; temperature
Abstract:
... This work investigates the CO₂ methanation rate of structured catalysts by tuning the geometry of 3D-printed metal Fluid Guiding Elements (FGEs) structures based on periodically variable pseudo-gyroid geometries. The enhanced performance showed by the structured catalytic systems is mostly associated with the capability of the FGEs substrate geometries for efficient heat usages. Thus, variations o ...
... This study reported that 5-sulfosalicylic acid (5-SSA), a solid acid with hydrotropic properties, could efficiently and rapidly fractionate poplar biomass in an aqueous solution at mild conditions. The experimental results showed that 5-SSA-treatment could deconstruct the biomass recalcitrant intercellular structure and has excellent potential in lignin and hemicellulose dissolution and glucose re ...
ambient temperature; ammonia; carbon; catalysts; durability; electrolysis; electron transfer; electrosynthesis; groundwater; nanotubes; nitrites; pH; pollutants; public health; surface area
Abstract:
... Nitrite (NO₂⁻) is a detrimental pollutant widely existing in groundwater sources, threatening public health. Electrocatalytic NO₂⁻ reduction settles the demand for removal of NO₂⁻ and is also promising for generating ammonia (NH₃) at room temperature. A nanotube array directly grown on a current collector not only has a large surface area, but also exhibits improved structural stability and accele ...
... Designing an earth-abundant electrode material with high activity and durability is a major challenge for water splitting to produce clean and green hydrogen energy. In this study, we report a novel high-performance electrocatalyst derived from a unique three-dimensional hierarchical network of two-dimensional iron-doped nickel selenide nanosheets (2D Fe-doped NiSe NSs) and high-quality carbon nan ...
adsorption; ammonia; atomic force microscopy; catalysts; density functional theory; electric field; electrochemistry; explosives; green chemistry; mass spectrometry; nitrate reductase; nitrates; solubility
Abstract:
... Nitrate has been commonly used in fertilizers, synthetic materials, and explosives; however, its irregular release leads to extensive contaminants in many sources of drinking water because of its high solubility and mobility. Unfortunately, efficient nitrate removal at low concentrations has been challenging for a long time. Inspired by nitrate reductase with iron as the active center in plants, w ...
... A novel type of chiral redox disulfonate iron complex for asymmetric catalysis is reported. The [Fe((Rₐ)-BINSate)]⁺ (BINSate = 1,1′-binaphthalene-2,2′-disulfonate) complex effectively promotes the enantioselective oxidative cross-coupling between 2-naphthols (1) and 2-aminonaphthalene derivatives (2), affording optically enriched (Rₐ)-2-amino-2′-hydroxy-1,1′-binaphthyls (NOBINs) with exceptional y ...
Sayanti Chatterjee; Ingolf Harden; Giovanni Bistoni; Rebeca G. Castillo; Sonia Chabbra; Maurice van Gastel; Alexander Schnegg; Eckhard Bill; James A. Birrell; Bill Morandi; Frank Neese; Serena DeBeer
... Herein, we study the mechanism of iron-catalyzed direct synthesis of unprotected aminoethers from olefins by a hydroxyl amine derived reagent using a wide range of analytical and spectroscopic techniques (Mössbauer, Electron Paramagnetic Resonance, Ultra-Violet Visible Spectroscopy, X-ray Absorption, Nuclear Resonance Vibrational Spectroscopy, and resonance Raman) along with high-level quantum ch ...
Tobias Gensch; Gabriel dos Passos Gomes; Pascal Friederich; Ellyn Peters; Théophile Gaudin; Robert Pollice; Kjell Jorner; AkshatKumar Nigam; Michael Lindner-D’Addario; Matthew S. Sigman; Alán Aspuru-Guzik
... The design of molecular catalysts typically involves reconciling multiple conflicting property requirements, largely relying on human intuition and local structural searches. However, the vast number of potential catalysts requires pruning of the candidate space by efficient property prediction with quantitative structure–property relationships. Data-driven workflows embedded in a library of poten ...
... It has been a long-standing challenge to create and identify the active sites of heterogeneous catalysts, because it is difficult to precisely control the interfacial chemistry at the molecular level. Here we report the synthesis and catalysis of a heteroleptic gold trihydride nanocluster, [Au₂₂H₃(dppe)₃(PPh₃)₈]³⁺ [dppe = 1,2-bis(diphenylphosphino)ethane, PPh₃ = triphenylphosphine]. The Au₂₂H₃ cor ...
X-ray diffraction; X-ray photoelectron spectroscopy; acetic acid; acetylene; catalysts; computer software; process design; reaction mechanisms; thermogravimetry; transmission electron microscopy; zinc
Abstract:
... A new catalyst, in situ Zn(CH₃COO)₂-NC, is prepared by a facile in situ generation method. With impregnation, drying, and high-temperature treatment, the precursor was obtained and then activated by acetic acid, generating Zn(OAc)₂-iNC catalyst in situ. According to X-ray diffraction, high-resolution transmission electron microscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, an ...
Shichao Ding; Zhaoyuan Lyu; Erik Sarnello; Mingjie Xu; Lingzhe Fang; Hangyu Tian; Sam Ellery Karcher; Tao Li; Xiaoqing Pan; John McCloy; Guodong Ding; Qiang Zhang; Qiurong Shi; Dan Du; Jin-Cheng Li; Xiao Zhang; Yuehe Lin
... Cost-effective and highly efficient Fe–N–C single-atom catalysts (SACs) have been considered to be one of the most promising potential Pt substitutes for the cathodic oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). Nevertheless, they are subject to severe oxidative corrosion originating from the Fenton reaction, leading to poor long-time durability of PEMFCs. Herei ...
amino alcohols; carbon; catalysts; catalytic activity; chemical bonding; chemical reactions; density functional theory; enantioselectivity
Abstract:
... The enantioselective total synthesis of madangamine E has been completed in 30 steps, enabled by a new catalytic and highly enantioselective desymmetrizing intramolecular Michael addition reaction of a prochiral ketone to a tethered β,β′-disubstituted nitroolefin. This key carbon–carbon bond forming reaction efficiently constructed a chiral bicyclic core in near-perfect enantio- and diastereo-sele ...
... Herein, a nitrogen doped carbon nanotube supported NiFe/NiSe₂ heterostructure rich in oxygen vacancies (DBD-NiFe/NiSe₂@NCNT) is successfully synthesized using atmospheric pressure dielectric barrier discharge plasma. It exhibits superior bifunctional catalytic activity towards the OER (η = 292 mV@10 mA cm⁻²) and ORR (E₁/₂ = 0.811 V), with a ΔE as low as 0.711 V in 0.1 M KOH electrolyte, outperform ...
... Environmental pollution by petroleum hydrocarbon is one of the significant concerns of the contemporary world. This paper deals with the relevant environmental issues concerning the oil pollution of the petroleum industry. There is a need for further development of sustainable remediation technologies. Nineteen petroleum-degrading bacteria were isolated from an oil-polluted soil in the Suez oil pr ...
... A new type of medium-chain-length-co-long-chain-length polyhydroxyalkanoate (mcl-co-lcl PHA) containing 39.25 mol% 3-hydroxyhexadecanoic (3HHD) was isolated from Bacillus thermoamylovorans strain PHA005 and utilized as biofuel substrate. A novel process to produce 3-hydroxyalkanoate methyl ester (3HAME) using mcl-co-lcl PHA was transesterification via an enzyme-catalysis was used. The optimal cond ...
... Three high-energy density fuels were generated in a one-pot reaction from the [4+4]-cyclodimerization and cross-coupling of isoprene and myrcene using a homogeneous iron pyridineimine (PDI) catalyst. The resulting mixture of C10, C15, and C20 regio- and chemoselectively synthesized cyclooctadienes was fractionally distilled to yield three fractions. The isolated cyclic hydrocarbons were then hydro ...
active sites; adsorption; ambient temperature; catalysts; catalytic activity; enantioselectivity; hydrogen; hydrogenation; kinetics; models; partial pressure; process design; regioselectivity; solvents
Abstract:
... This communication proposes a preliminary simplified kinetic model for the hydrogenation of 1-phenyl-1,2-propanedione that can render up to eight compounds, involving regioselectivity and enantioselectivity. The catalytic system comprises two functionalities; the heterogeneous catalyst (Ir/TiO₂) plays the role for the hydrogenation, whereas the adsorption/binding to the active site is played by a ...
Lewis acids; amination; aniline; benzaldehyde; boranes; boron; catalysts; chemoselectivity; density functional theory; hydrogenation; imines; organic chemistry
Abstract:
... Density functional theory calculations are used in this study to investigate the product selectivity and mechanism of borane-catalyzed reductive aldehyde amination by a H₂ reducing agent. Knowing that different boranes yield different products, two typical boranes, (B(2,6-Cl₂C₆H₃)(p-HC₆F₄)₂ and B(C₆F₅)₃), are studied. Of the seven possible pathways of B(2,6-Cl₂C₆H₃)(p-HC₆F₄)₂-catalyzed aldehyde am ...
Donglin Zhao; Jie Liang; Jun Li; Longcheng Zhang; Kai Dong; Luchao Yue; Yongsong Luo; Yuchun Ren; Qian Liu; Mohamed S. Hamdy; Quan Li; Qingquan Kong; Xuping Sun
... Electrocatalytic nitrite reduction not only holds significant potential in the control of nitrite contamination in the natural environment, but also is an attractive approach for sustainable ammonia synthesis. In this communication, we report that a TiO₂₋ₓ nanobelt array with oxygen vacancies on a titanium plate is able to convert nitrite into ammonia with a high faradaic efficiency of 92.7% and a ...
... The disposal of polychlorinated biphenyls (PCBs) as persistent organic pollutants from the environment has been normally performed by isolation from soil or water because of their biological activity and toxic potential. In the present investigation, catalytic hydrodehalogenation was used to detoxify PCBs-contaminated transformer oil. All reactions were directed on an oil containing 11.09 wt% of P ...
... Catalytic hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) was investigated over four different types of mesoporous silica (SBA-15, MCM-48, MCM-41, and KIT-6) supported copper (5 wt.%) catalysts. The Cu was incorporated into mesoporous silica supports by a sequential impregnation method. A detailed investigation of the support structure–activity correlation and the performance of the ...
... With increasingly serious environmental pollution and the production of various wastewater, water pollutants have posed a serious threat to human health and the ecological environment. The advanced oxidation process (AOP), represented by the persulfate (PS) oxidation process, has attracted increasing attention because of its economic, practical, safety and stability characteristics, opening up new ...
... Silicoaluminophosphate-34 (SAPO-34) is a molecular sieve with a unique shape structure and pore framework, favorable acidic properties, and excellent stability under different operating conditions. These unique properties have made SAPO-34 an important material with widespread applications as a catalyst, membrane, and adsorbent in different processes. As a catalyst, SAPO-34 is utilized in converti ...
catalysts; catalytic activity; energy efficiency; environment; human health; reaction mechanisms; volatile organic compounds
Abstract:
... It is urgent to control the emission of volatile organic compounds (VOCs) due to their harmful effects on the environment and human health. A hybrid system integrating non-thermal-plasma and catalysis is regarded as one of the most promising technologies for VOCs removal due to their high VOCs removal efficiency, product selectivity and energy efficiency. This review systematically documents the m ...
ambient temperature; catalysts; energy conversion; foams; hydrogen production; nanosheets; nickel; transmission electron microscopy
Abstract:
... The development of low-cost and high-efficiency electrocatalysts is very important for electrocatalytic hydrogen evolution reaction (HER) in water splitting system. Herein, ultrathin rhodium-iridium nanosheets were facilely in-situ grown on nickel foam (RhIr NSs/NF) by a one-pot aqueous strategy at room temperature. The sheet-like structures with the film thickness of 78 nm were identified by scan ...
ammonium sulfate; catalysts; chemical structure; cotton fabric; electronics; films (materials); fluorescence; green chemistry; hydrogels; hydrogen; light microscopy; oleogels; semiconductors
Abstract:
... Using natural processes as a guiding tool, the scientific community is actively involved in achieving substantial advances at the interface of supramolecular chemistry and materials design. In this paper, we have synthesized a series of amphiphilic N-glycosyl naphthalimides using environmentally benign protocols in good yields. For the first time, an exclusive formation of β-anomeric product using ...
... The deoiling process is a critical issue in catalyst regeneration and recovery of precious metals from spent catalysts. This study developed a fast and efficient method to recover crude oil from spent hydrodesulphurization (HDS) catalysts. We employed four solvents (p-xylene, acetone, dichloromethane, and n-hexane) with different polar and aromatic properties to remove crude oil from the spent cat ...
... Multilayered, spatially ordered and highly permeable three-dimensional cross-network porous carbons were prepared from waste superabsorbent polymer (SAP) and were used as supports for NiMo hydrodesulfurization (HDS) catalysts. The acidified SAP-based carbon support and the corresponding catalyst were characterized by FT-IR, XRD, N₂ adsorption–desorption, NH₃-TPD, TG, SEM, TEM, XPS and H₂-TPR. The ...
additives; catalysts; catalytic activity; chemical communication; forces; mechanochemistry; methodology; milling
Abstract:
... Direct mechanocatalysis (DM) describes solvent-free catalytic reactions that are initiated by mechanical forces in mechanochemical reactors such as ball mills. The distinctive feature of DM is that the milling materials, e.g. the milling balls themselves are the catalyst of the reaction. In this article we follow the historical evolution of this novel concept and give a guide to this emerging, pow ...
... The regulatory control on dyes is an important issue, as their discharge into the environment can pose significant risks to human health. MIL-101(Fe) prepared by a solvothermal method was used as a catalyst to generate sulfate (SO₄•⁻) and hydroxyl (HO•) radicals from peroxymonosulfate (PMS) for the treatment of orange G (OG). The structural properties of MIL-101(Fe) were assessed by a number of ch ...
... Doping FeNC catalysts with heteroatoms has been widely recognized as a most promising way to improve the electrocatalytic activity to achieve the replacement of Pt-based electrocatalysts for efficient oxygen reduction reaction (ORR). However, it is still a challenge to combine delicate control of the catalyst structure with heteroatom-doping to achieve optimal electrocatalytic efficiency. Herein, ...