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You searched for: Subject methanol Remove constraint Subject: methanol Subject hydroxyl radicals Remove constraint Subject: hydroxyl radicals Subject term catalysts Remove constraint Subject term: catalysts
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1. Cubic platinum nanoparticles capped with Cs2[closo-B12H12] as an effective oxidation catalyst for converting methane to ethanol

Author:
Zhengxi Wang; Yi Liu; Haibo Zhang; Xiaohai Zhou
Source:
Journal of colloid and interface science 2020 v.566 pp. 135-142
ISSN:
0021-9797
Subject:
carbon; catalysts; chemical bonding; electron paramagnetic resonance spectroscopy; energy; ethanol; free radicals; hydrogen peroxide; hydroxyl radicals; methane; methanol; nanoparticles; oxidation; oxygen; platinum
Abstract:
... Direct conversion of methane to alcohol remains a key challenge. Here, we report a novel aqueous catalyst, cubic platinum (Pt) nanoparticles capped with Cs₂[closo-B₁₂H₁₂], capable of direct oxidation of methane to ethanol and methanol with H₂O₂ and O₂ under facile conditions. The selective conversion to ethanol exceeded 97% with a yield reaching 148.41 mol·kgcₐₜ⁻¹·h⁻¹ at 50 °C. Experiments with 5, ...
DOI:
10.1016/j.jcis.2020.01.047

2. Investigation of Matrix Effects in Laboratory Studies of Catalytic Ozonation Processes

Author:
Wenwen Yang; Tingting Wu
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.8 pp. 3468-3477
ISSN:
1520-5045
Subject:
adsorption; borates; catalysts; electron transfer; hydroxyl radicals; methanol; models; oxalates; oxidation; ozonation; ozone; pH; phosphates; process design; silica
Abstract:
... A systematic study investigating the effects of water matrices on heterogeneous catalytic ozonation processes was conducted in a semibatch reactor at initial pH 7.00 ± 0.20. Specifically, three matrices commonly used in laboratory studies were tested: deionized (DI) water, phosphate buffered solution, and tetra-borate buffered solution. Three metal oxide catalysts on SiO₂ support, CuO/SiO₂, Fe₂O₃/ ...
DOI:
10.1021/acs.iecr.8b05465

3. Promotional effect of short‐chain saturated alcohols on Fe3O4‐catalyzed decomposition of H2O2 and its application in selective oxidation of benzyl alcohol

Author:
Jiawei Zhang; Shiwei Xiao; Rong Chen; Fengxi Chen
Source:
Journal of chemical technology and biotechnology 2019 v.94 no.5 pp. 1613-1621
ISSN:
0268-2575
Subject:
Lewis bases; benzyl alcohol; biotechnology; catalysts; catalytic activity; ethanol; glycerol; hydrogen peroxide; hydroxyl radicals; iron; magnetism; magnetite; methanol; microparticles; oxidation; pollutants; remediation
Abstract:
... BACKGROUND: Hydrogen peroxide (H₂O₂) has been used widely in diverse areas of biotechnology, environmental remediation and organic synthesis wherein its catalytic activation to generate reactive oxygen species (e.g. hydroxyl radicals) is of vital importance. Magnetite (Fe₃O₄) microspheres are attractive heterogeneous peroxidase‐like catalysts due to many technological advantages (e.g. biocompatibl ...
DOI:
10.1002/jctb.5929

4. Simultaneous degradation of the anticancer drugs 5-fluorouracil and cyclophosphamide using a heterogeneous photo-Fenton process based on copper-containing magnetites (Fe3-xCuxO4)

Author:
Elissandro Soares Emídio; Peter Hammer; Raquel F. Pupo Nogueira
Source:
Chemosphere 2020 v.241 pp. 124990
ISSN:
0045-6535
Subject:
X-radiation; X-ray diffraction; X-ray fluorescence spectroscopy; X-ray photoelectron spectroscopy; catalysts; catalytic activity; copper; cyclophosphamide; fluorescence; fluorouracil; free radical scavengers; hydrogen peroxide; hydroxyl radicals; ions; iron; leaching; magnetite; methanol; nanoparticles; oxidation; pH; scanning electron microscopy; surface area; umbelliferones
Abstract:
... The effect of substitution of iron by copper in the magnetite lattice was investigated in terms of the catalytic activity in the heterogeneous photo-Fenton process. The physicochemical properties of the Fe₃₋ₓCuₓO₄ nanoparticles were characterized by X-ray diffraction (XRD), X-ray fluorescence (WD-XRF), specific surface area measurements, field emission scanning electron microscopy (FEG-SEM), and X ...
DOI:
10.1016/j.chemosphere.2019.124990

5. Insights into the mechanism of persulfate activated by rice straw biochar for the degradation of aniline

Author:
Yao Wu; Jing Guo; Yijie Han; Junyi Zhu; Lixiang Zhou; Yeqing Lan
Source:
Chemosphere 2018 v.200 pp. 373-379
ISSN:
0045-6535
Subject:
EDTA (chelating agent); aniline; biochar; catalysts; electron paramagnetic resonance spectroscopy; free radicals; hydroxyl radicals; methanol; organic carbon; pH; rice straw
Abstract:
... This study investigated the degradation of aniline by persulfate (PS) activated with rice straw biochar (RSBC). The results demonstrate that aniline could be rapidly decomposed by a combination of PS and RSBC. The degradation efficiency of aniline was up to 94.1% within 80 min, and meanwhile 52% of the total organic carbon was removed. In the initial pH range of 3–9, aniline could be efficiently r ...
DOI:
10.1016/j.chemosphere.2018.02.110

6. Photo-assisted catalytic degradation of acetaminophen using peroxymonosulfate decomposed by magnetic carbon heterojunction catalyst

Author:
Mohammad Noorisepehr; Khashayar Ghadirinejad; Babak Kakavandi; Amirhosein Ramazanpour Esfahani; Anvar Asadi
Source:
Chemosphere 2019 v.232 pp. 140-151
ISSN:
0045-6535
Subject:
acetaminophen; adsorption; aqueous solutions; batch systems; carbon; catalysts; decontamination; free radicals; hydroxyl radicals; ions; iron; magnetic materials; magnetism; methanol; oxidation; porous media; synergism; ultraviolet radiation
Abstract:
... Catalytic oxidative degradation of acetaminophen (ACT) was evaluated using magnetic mesoporous carbon (MNPs@C) coupled with UV light and peroxymonosulfate (PMS). The performance of hybrid system (i.e., MNPs@C/UV/PMS) was assessed as a function of some operational factors (e.g., reaction time and different concentrations of catalyst, PMS and ACT) in a batch system. MNPs@C represented a high magneti ...
DOI:
10.1016/j.chemosphere.2019.05.070

7. Activation of peroxymonosulfate by surfactants as the metal-free catalysts for organic contaminant removal

Author:
Qing Yue; Yuyuan Yao; Lianshun Luo; Tao Hu; Liang Shen
Source:
Environmental science and pollution research international 2017 v.24 no.33 pp. 26069-26078
ISSN:
0944-1344
Subject:
ammonium; anions; bromides; catalysts; catalytic activity; cationic surfactants; cetyltrimethylammonium bromide; electron paramagnetic resonance spectroscopy; electrostatic interactions; hydroxyl radicals; methanol; micelles; oxidation; pollutants; wastewater treatment
Abstract:
... The present work described that tertiary ammonium surfactants containing bromide ion as novel metal-free catalysts were innovatively coupled with peroxymonosulfate (PMS) to build a simple catalytic oxidation system, possessing outstanding catalytic ability with organic dye Reactive Red M-3BE (RR M-3BE) as the target pollutant. Furthermore, cetyltrimethylammonium bromide (CTAB), a representative of ...
DOI:
10.1007/s11356-017-0210-0

8. Enzymatic esterification of acid oil from soapstocks obtained in vegetable oil refining: Effect of enzyme concentration

Author:
Mariana Cruz; Sílvia Cardinal Pinho; Ricardo Mota; Manuel Fonseca Almeida; Joana Maia Dias
Source:
Renewable energy 2017 pp. -
ISSN:
0960-1481
Subject:
Thermomyces lanuginosus; acidity; carboxylic ester hydrolases; catalysts; esterification; hydroxyl radicals; methanol; mixing; oil refining; renewable energy sources; soapstock; sulfur; temperature; vegetable oil; wastes
Abstract:
... The enzymatic esterification of an acid waste oil was investigated using a commercial lipase (Thermomyces lanuginosus) in batch reactors, under the following reaction conditions: temperature of 35 °C, molar ratio of acid:alcohol of 1:1.5, vigorous magnetic stirring and enzyme concentration from 2 to 5 wt.%. The reaction progressed during 24 h. The acid oil obtained from soapstock of vegetable oil ...
DOI:
10.1016/j.renene.2017.06.053

9. Graphene: A new activator of sodium persulfate for the advanced oxidation of parabens in water

Author:
Leonidas Bekris; Zacharias Frontistis; George Trakakis; Lamprini Sygellou; Costas Galiotis; Dionissios Mantzavinos
Source:
Water research 2017 v.126 pp. 111-121
ISSN:
0043-1354
Subject:
catalysts; free radical scavengers; free radicals; graphene; hydroxyl radicals; methanol; methylparaben; organic matter; oxidants; oxidation; pH; pollutants; sodium; sulfates; wastewater
Abstract:
... Graphene was successfully employed as a catalyst for the activation of sodium persulfate, towards the effective degradation of propylparaben, an emerging micro-pollutant, representative of the parabens family. A novel process is proposed which utilizes a commercial graphene nano-powder as the catalyst and sodium persulfate as the oxidizing agent. It was found that over 95% of micro-pollutant degra ...
DOI:
10.1016/j.watres.2017.09.020

10. Magnetic cobalt ferrite composite as an efficient catalyst for photocatalytic oxidation of carbamazepine

Author:
Yongzhen He; Chaomeng Dai; Xuefei Zhou
Source:
Environmental science and pollution research international 2017 v.24 no.2 pp. 2065-2074
ISSN:
0944-1344
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; aqueous solutions; catalysts; cobalt; coprecipitation; drugs; energy-dispersive X-ray analysis; ferrimagnetic materials; gas chromatography-mass spectrometry; hydroxyl radicals; ions; iron; iron oxides; magnetic properties; methanol; nanocomposites; nanoparticles; oxidation; pH; personal care products; photocatalysis; photolysis; scanning electron microscopy; transmission electron microscopy; ultraviolet radiation
Abstract:
... A magnetic spinel cobalt ferrite nanoparticle composite (CFO) was prepared via an ultrasonication-assisted co-precipitation method. The morphological structure and surface composition of CFO before and after reaction were investigated by using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray, and Fourier transform infrared spectroscopy, ind ...
DOI:
10.1007/s11356-016-7978-1

11. Photocatalytic abatement of trichlorethylene over Au and Pd–Au supported on TiO2 by combined photomineralization/hydrodechlorination reactions under simulated solar irradiation

Author:
Razvan State; Florica Papa; Tatyana Tabakova; Irina Atkinson; Catalin Negrila; Ioan Balint
Source:
Journal of catalysis 2017 v.346 pp. 101-108
ISSN:
0021-9517
Subject:
carbon dioxide; catalysts; chlorides; dechlorination; electrons; ethane; ethylene; free radicals; gold; hydrogen; hydrogenation; hydroxyl radicals; methanol; nanogold; nanoparticles; palladium; photocatalysis; photooxidation; reaction mechanisms; solar radiation; titanium dioxide
Abstract:
... The present work investigates the photocatalytical abatement of trichlorethylene (TCE) under simulated solar irradiation (AM 1.5). The employed catalytic materials, Au and Pd–Au nanoparticles supported on TiO2, were prepared by incipient wetness and by deposition–precipitation methods. It is found out that TCE is converted efficiently (>80%) to Cl⁻ and CO2 over all scrutinized catalysts. Typically ...
DOI:
10.1016/j.jcat.2016.11.032

12. Sub-4 nm PtZn Intermetallic Nanoparticles for Enhanced Mass and Specific Activities in Catalytic Electrooxidation Reaction

Author:
Qi Zhiyuan; Xiao Chaoxian; Liu Cong; Goh Tian Wei; Zhou Lin; Maligal-Ganesh Raghu; Pei Yuchen; Li Xinle; Curtiss Larry A.; Huang Wenyu
Source:
Journal of the American Chemical Society 2017 v.139 no.13 pp. 4762-4768
ISSN:
1520-5126
Subject:
carbon nanotubes; catalysts; fuel cells; hydroxyl radicals; methanol; methodology; nanoparticles; oxidation; porous media; prediction; silica; temperature; zinc
Abstract:
... Atomically ordered intermetallic nanoparticles (iNPs) have sparked considerable interest in fuel cell applications by virtue of their exceptional electronic and structural properties. However, the synthesis of small iNPs in a controllable manner remains a formidable challenge because of the high temperature generally required in the formation of intermetallic phases. Here we report a general metho ...
DOI:
10.1021/jacs.6b12780

13. Production of Isopropyl and Methyl Esters from Yellow Mustard Oil/IPA Miscellas

Author:
Sayeh Sinichi; David G. B. Boocock; Levente L. Diosady
Source:
The journal of the American Oil Chemists' Society 2017 v.94 no.3 pp. 485-495
ISSN:
0003-021X
Subject:
adsorption; biodiesel; catalysts; esters; feedstocks; flour; fuel production; hydroxyl radicals; isopropyl alcohol; methanol; mustard oil; phospholipids; potassium hydroxide; sieves; solvents; sulfuric acid; transesterification
Abstract:
... Using an isopropyl alcohol (IPA):flour [volume:weight (ml:g)] ratio of 1.5:1 per stage of extraction resulted in an oil yield of 86.3%. The combined miscella (IPA + oil), which contained 90.6 wt% IPA, 9.8 wt% oil, and 2.1 wt% water, was used as a feedstock for biodiesel production by transesterification. Transesterification of the IPA/oil miscella dehydrated using adsorption on 4Å molecular sieves ...
DOI:
10.1007/s11746-016-2942-2

14. The mechanism of degradation of bisphenol A using the magnetically separable CuFe2O4/peroxymonosulfate heterogeneous oxidation process

Author:
Yin Xu; Jia Ai; Hui Zhang
Source:
Journal of hazardous materials 2016 v.309 pp. 87-96
ISSN:
0304-3894
Subject:
X-ray photoelectron spectroscopy; anions; aqueous solutions; bisphenol A; catalysts; chlorides; copper; electron paramagnetic resonance spectroscopy; fluorides; free radical scavengers; free radicals; hydroxyl radicals; iron; magnetism; methanol; methylene blue; mineralization; nanoparticles; oxidation; pH; perchlorates
Abstract:
... The removal of bisphenol A (BPA) in aqueous solution by an oxidation process involving peroxymonosulfate (PMS) activated by CuFe2O4 magnetic nanoparticles (MNPs) is reported herein. The effects of PMS concentration, CuFe2O4 dosage, initial pH, initial BPA concentration, catalyst addition mode, and anions (Cl⁻, F⁻, ClO4⁻ and H2PO4⁻) on BPA degradation were investigated. Results indicate that nearly ...
DOI:
10.1016/j.jhazmat.2016.01.023

15. Enhancing Aromatic Production from Reductive Lignin Disassembly: in Situ O-Methylation of Phenolic Intermediates

Author:
Barrett Jacob A.; Gao Yu; Bernt Christopher M.; Chui Megan; Tran Anthony T.; Foston Marcus B.; Ford Peter. C.
Source:
ACS sustainable chemistry 2016 v.4 no.12 pp. 6877-6886
ISSN:
2168-0485
Subject:
aromatic compounds; biomass; catalysts; copper; gas chromatography-mass spectrometry; hydrogenation; hydroxyl radicals; lignin; methanol; methylation; models; nuclear magnetic resonance spectroscopy; phosphorus; stable isotopes
Abstract:
... The selective conversion of lignin into aromatic compounds has the potential to serve as a “green” alternative to the production of petrochemical aromatics. Herein, we evaluate the addition of dimethyl carbonate (DMC) to a biomass conversion system that uses a Cu-doped porous metal oxide (Cu₂₀PMO) catalyst in supercritical methanol (sc-MeOH) to disassemble lignin with little to no char formation. ...
DOI:
10.1021/acssuschemeng.6b01827

16. Structure and reactivity of ZSM-5 supported oxalate ligand functionalized nano-Fe catalyst for low temperature direct methane conversion to methanol

Author:
Olumide Bolarinwa Ayodele
Source:
Energy conversion and management 2016 v.126 pp. 537-547
ISSN:
0196-8904
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; carbonates; catalysts; cleavage (chemistry); energy-dispersive X-ray analysis; hydrogen peroxide; hydroxyl radicals; iron; iron oxides; ligands; methane; methanol; oxalates; temperature
Abstract:
... The feasibility of low temperature direct methane conversion to methanol (DMCM) over ferrioxalate supported on ZSM-5 catalyst (FeOx/ZSM-5) was investigated in this study. FeOx/ZSM-5 was synthesized via functionalization of Fe with oxalate ligand and employed to generate hydroxyl radicals (HO) from hydrogen peroxide (HP) in a Fenton-like process to activate the methane CH bond scission to form meth ...
DOI:
10.1016/j.enconman.2016.08.016

17. Effect of System Conditions for Biodiesel Production via Transesterification Using Carbon Dioxide–Methanol Mixtures in the Presence of a Heterogeneous Catalyst

Author:
Soh Lindsay; Curry Joshua; Beckman Eric J.; Zimmerman Julie B.
Source:
ACS sustainable chemistry 2014 v.2 no.3 pp. 387-395
ISSN:
2168-0485
Subject:
biodiesel; carbon; carbon dioxide; catalysts; experimental design; fuel production; glycerol; hydroxyl radicals; mass transfer; methanol; oleic acid; solubility; temperature; transesterification; triolein
Abstract:
... A mixed carbon dioxide (CO₂) and methanol (MeOH) system is shown to successfully transesterify triolein into methyl oleate at moderate pressures and temperatures below 100 °C in the presence of Nafion NR50, a heterogeneous catalyst. An experimental design was developed to explore the effects of mono-, bi-, and tri-phasic CO₂–MeOH–triolein systems through pressure, temperature, and methanol loading ...
DOI:
10.1021/sc400349g

18. Role of the Chemically Non-Innocent Ligand in the Catalytic Formation of Hydrogen and Carbon Dioxide from Methanol and Water with the Metal as the Spectator

Author:
Li Haixia; Hall Michael B.
Source:
Journal of the American Chemical Society 2015 v.137 no.38 pp. 12330-12342
ISSN:
1520-5126
Subject:
carbon dioxide; catalysts; dehydrogenation; formaldehyde; formates; formic acid; hydrides; hydrogen; hydroxyl radicals; ligands; methanol; methodology; ruthenium
Abstract:
... The catalytic mechanism for the production of H₂ and CO₂ from CH₃OH and H₂O by [K(dme)₂][Ru(H) (trop₂dad)] (K(dme)₂.1_exp) was investigated by density functional theory (DFT) calculations. Since the reaction occurs under mild conditions and at reasonable rates, it could be considered an ideal way to use methanol to store hydrogen. The predicted mechanism begins with the dehydrogenation of methanol ...
DOI:
10.1021/jacs.5b07444

19. The influence of structure and surface chemistry of carbon materials on the decomposition of hydrogen peroxide

Author:
Rui S. Ribeiro; Adrián M.T. Silva; José L. Figueiredo; Joaquim L. Faria; Helder T. Gomes
Source:
Carbon 2013 v.62 no. pp. 97-108
ISSN:
0008-6223
Subject:
activated carbon; active sites; aqueous solutions; carbon nanotubes; catalysts; graphene; hydrogen peroxide; hydroxyl radicals; methanol; physicochemical properties; sulfur; sulfuric acid
Abstract:
... Carbon materials with different structural and chemical properties, namely activated carbons, carbon xerogels, carbon nanotubes, graphene oxide, graphite and glycerol-based carbon materials, were tested under different operating conditions for their ability to catalyse hydrogen peroxide (H₂O₂) decomposition in aqueous solutions. Activated carbons treated with concentrated sulphuric acid (ACS) are ...
DOI:
10.1016/j.carbon.2013.06.001

20. Deactivation and in Situ Regeneration of Anion Exchange Resin in the Continuous Transesterification for Biodiesel Production

Author:
He Benqiao; Ren Yanbiao; Cheng Yu; Li Jianxin
Source:
Energy & Fuels 2012 v.26 no.6 pp. 3897-3902
ISSN:
1520-5029
Subject:
X-ray photoelectron spectroscopy; adsorption; anion exchange resins; biodiesel; catalysts; catalytic activity; desorption; fouling; fuel production; glycerol; hydroxyl radicals; methanol; nitrogen; organic matter; scanning electron microscopes; scanning electron microscopy; soybean oil; transesterification; triacylglycerols
Abstract:
... The deactivation and in situ regeneration of anion exchange resin (D261) used as a catalyst in the continuous transesterification of soybean oil with methanol for biodiesel production were studied in a fixed-bed reactor. The chemical and physical structures of the resins were investigated by means of X-ray photoelectron spectrometer (XPS), N₂ adsorption/desorption isotherms, and scanning electron ...
DOI:
10.1021/ef300524w