110-16-7Relevant articles and documents
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Yokoyama,Yamamoto
, p. 121,123 (1943)
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Yokoyama,Ishikawa
, p. 275,281 (1931)
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Fabrication of a stable Ti/Pb-TiOxNWs/PbO2 anode and its application in benzoquinone degradation
Guo, Yingjuan,Tang, Changbin,Xue, Juanqin,Yu, Lihua,Zhang, Lihua
, (2021)
To delay passivation of a titanium (Ti) substrate as well as enhance adhesion between an electrodeposited PbO2 coating and the Ti substrate, a titanium-lead composite oxide nanowire (Pb-TiOxNWs) intermediate layer was formed in situ on the surface of porous Ti by alkali etching, ion substitution, and high-temperature calcination. At the same time, Ti/PbO2 and Ti/TiO2NWs/PbO2 electrodes with porous Ti as a matrix were prepared for comparison. The surface structure and morphology of the prepared intermediate layer and the PbO2 coating were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The influences of the composite oxide intermediate layer on the electrochemical performance of the PbO2 electrode were analyzed by cyclic voltammetry (CV), linear sweep voltammetry (LSV), and AC impedance spectroscopy (EIS). Accelerated lifetime tests were performed for electrodes with and without different intermediate layers. The results showed that PbOx was incorporated into the titanium dioxide three-dimensional network structure, resulting in formation of Pb-TiOxNWs. The surface of the Ti/Pb-TiOxNWs/PbO2 electrode was denser due to the smaller particle size of PbO2. The preferred crystal orientation of β(110) was observed for PbO2 deposited on Ti/Pb-TiOxNWs. The oxygen evolution potential reached a maximum of 2.19 V for Ti/Pb-TiOxNWs/PbO2. Accelerated life tests showed that compared with Ti/PbO2 and Ti/TiO2NWs/PbO2, the electrode life of Ti/Pb-TiOxNWs/PbO2 was increased by 91.7% and 35.3%, respectively. Therefore, it can be concluded that significantly improved morphology and electrochemical performance were achieved for titanium-based PbO2 electrodes by the addition of a Pb-TiOxNWs intermediate layer. In particular, the electrochemical stability of the PbO2 coating electrodes was improved markedly by the Pb-TiOxNWs intermediate layer. The electrodes were used for electrochemical oxidation of benzoquinone in wastewater (100 mg/L). It was found that chloride ions played a critical role in improving the current efficiency of electro-oxidative degradation. Under the same conditions, the COD removal rate in the presence of NaCl was 45% higher than in the presence of sulfate. The results of HPLC analysis of the intermediate products indicated that the oxidants electro-generated by chloride ions had stronger ring-opening and mineralization capabilities than those electro-generated by sulfate ions.
Reactions of Ozone with 1-(m-Substituted phenylazo)-2-naphthol-6-sulfonic Acids in Aqueous Solutions
Onari, Yasuo
, p. 2526 - 2530 (1985)
The substituent effect on the ozone decoloration of 1-(m-substituted phenylazo)-2-naphthol-6-sulfonic acids (PANSA) in aqueous solutions was investigated.Both the acidities of PANSA and the variation of the ozone decoloration rates of them increased compared to those of the corresponding 1-(m-substituted phenylazo)-2-naphthol-3,6-disulfonic acids (PANDSA).The relationships between the decoloration rates and the indexes (pKOH and ?m values) of the basicities of the dyes, however, indicated nearly the same characteristics between the data of these two series of dyes, and the ozone decoloration reactions of PANSA appeared to proceed by nearly the same mechanism as those of PANDSA.The changes of the keto-enol ratios of the dyes with their ozone decolorations suggested that the decoloration rates might rise as the reduction rates of their keto-enol ratios increased.It seems likely that the chief organic product that was finally produced in these resctions is oxalic acid.
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Parks,Yula
, p. 891,896 (1941)
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Degradation of the Cellulosic Key Chromophore 5,8-Dihydroxy-[1,4]-naphthoquinone by Hydrogen Peroxide under Alkaline Conditions
Zwirchmayr, Nele Sophie,Hosoya, Takashi,Henniges, Ute,Gille, Lars,Bacher, Markus,Furtmüller, Paul,Rosenau, Thomas
, p. 11558 - 11565 (2017)
5,8-Dihydroxy-[1,4]-naphthoquinone (DHNQ) is one of the key chromophores in cellulosic materials. Its almost ubiquitous presence in cellulosic materials makes it a target molecule of the pulp and paper industry's bleaching efforts. In the presented study, DHNQ was treated with hydrogen peroxide under alkaline conditions at pH 10, resembling the conditions of industrial hydrogen peroxide bleaching (P stage). The reaction mechanism, reaction intermediates, and final degradation products were analyzed by UV/vis, NMR, GC-MS, and EPR. The degradation reaction yielded C1-C4 carboxylic acids as the final products. Highly relevant for pulp bleaching are the findings on intermediates of the reaction, as two of them, 2,5-dihydroxy-[1,4]-benzoquinone (DHBQ) and 1,4,5,8-naphthalenetetrone, are potent chromophores themselves. While DHBQ is one of the three key cellulosic chromophores and its degradation by H2O2 is well-established, the second intermediate, 1,4,5,8-naphthalenetetrone, is reported for the first time in the context of cellulose discoloration.
Synthesis of maleic acid from renewable resources: Catalytic oxidation of furfural in liquid media with dioxygen
Shi, Song,Guo, Huajun,Yin, Guochuan
, p. 731 - 733 (2011)
Developing novel technologies to obtain fuel and organic chemicals from renewable resources has been the immediate issue in academic and industrial communities. The present work introduces a new route to synthesize maleic acid from the renewable furfural. The current data reveal that, using dioxygen as oxidant, the simple copper salts can catalyze oxidation of furfural to maleic acid in aqueous solution. The combination of copper nitrate with phosphomolybdic acid could achieve a 49.2% yield of maleic acid with selectivity of 51.7%. The major challenge for this route is how to avoid the polymerization of furfural to resins under oxidative conditions.
An electrocatalytic route for transformation of biomass-derived furfural into 5-hydroxy-2(5H)-furanone
Wu, Haoran,Song, Jinliang,Liu, Huizhen,Xie, Zhenbing,Xie, Chao,Hu, Yue,Huang, Xin,Hua, Manli,Han, Buxing
, p. 4692 - 4698 (2019)
Development of efficient strategies for biomass valorization is a highly attractive topic. Herein, we conducted the first work on electrocatalytic oxidation of renewable furfural to produce the key bioactive intermediate 5-hydroxy-2(5H)-furanone (HFO). It was demonstrated that using H2O as the oxygen source and metal chalcogenides (CuS, ZnS, PbS, etc.) as electrocatalysts, the reaction could proceed efficiently, and the CuS nanosheets prepared in this work showed the best performance and provided high HFO selectivity (83.6%) and high conversion (70.2%) of furfural. In addition, the CuS electrocatalyst showed long-term stability. Mechanism investigation showed that furfural was oxidized to HFO via multistep reactions, including C-C cleavage, subsequent ring opening and oxidation, and intramolecular isomerization.
Active sites in vanadia/titania catalysts for selective aerial oxidation of β-picoline to nicotinic acid
Srinivas, Darbha,Hoelderich, Wolfgang F.,Kujath, Steffen,Valkenberg, Michael H.,Raja, Thirumalaiswamy,Saikia, Lakshi,Hinze, Ramona,Ramaswamy, Veda
, p. 165 - 173 (2008)
Vanadia/titania catalysts with varying vanadium content were prepared by impregnation using three different titania carrier materials of varying surface area. The structure of active vanadium species for β-picoline oxidation was investigated. Vanadium is mainly in the +5 oxidation state as revealed by electron paramagnetic resonance (EPR) and 51V magic-angle spinning nuclear magnetic resonance (51V MAS NMR) spectroscopy techniques. Diffuse reflectance UV-visible (DRUV-vis) spectroscopy and spectral deconvolution enabled identification of at least five different types of vanadium oxide species in these catalysts: monomeric tetrahedral VO3-4, polymeric distorted tetrahedral VO-3, square pyramidal V2O5, octahedral V2O2-6 and V4+ oxide species. While both VO3-4 and VO-3 species are active in β-picoline oxidation, the latter having a distorted tetrahedral geometry yielded the desired products-picolinaldehyde and nicotinic acid. High surface area, anatase structure for the support and dispersed, distorted tetrahedral vanadium oxide species are the key parameters determining the activity and selectivity of these oxidation catalysts.
Robust selenium-doped carbon nitride nanotubes for selective electrocatalytic oxidation of furan compounds to maleic acid
Huang, Xin,Song, Jinliang,Hua, Manli,Chen, Bingfeng,Xie, Zhenbing,Liu, Huizhen,Zhang, Zhanrong,Meng, Qinglei,Han, Buxing
, p. 6342 - 6349 (2021)
Selective oxidation of biomass-derived furan compounds to maleic acid (MA), an important bulk chemical, is a very attractive strategy for biomass transformation. However, achieving a high MA selectivity remains a great challenge. Herein, we for the first time successfully designed and fabricated Se-doped graphitic carbon nitride nanotubes with a chemical formula of C3.0N-Se0.03. The prepared C3.0N-Se0.03 was highly efficient for electrocatalytic oxidation of various biomass-derived furan compounds to generate MA. At ambient conditions, the MA yield could reach 84.2% from the electro-oxidation of furfural. Notably, the substituents on the furan ring significantly affected the selectivity to MA, following the order: carboxyl group > aldehyde group > hydroxyl group. Detailed investigation revealed that Se doping could tune the chemical structure of the materials (e.g., C3.0N-Se0.03 and g-C3N4), thus resulting in the change in catalytic mechanism. The excellent performance of C3.0N-Se0.03 originated from the suitable amount of graphitic N and its better electrochemical properties, which significantly boosted the oxidation pathway to MA. This work provides a robust and selective metal-free electrocatalyst for the sustainable synthesis of MA from oxidation of biomass-derived furan compounds. This journal is
Synthesis, analysis and possibility application of cyclic and linear forms of poly(aspartic acid) synthesized under microwave irradiation
Pielichowski,Polaczek,Hebda
, p. 120 - 127 (2010)
In this paper a new original method of synthesis of poly(aspartic acid) (PAA) from aspartic acid (AA) or maleic anhydride under microwave irradiation is presented. The syntheses carried out mainly without the catalyst, received higher yield in comparison for conventional method. PAA has been characterized by nuclear magnetic resonance (1H NMR, 13C NMR), infrared spectroscopy (FT-IR) and termogravimetric analysis (Tg). Obtained polymer we used for several diversified applications, such as, medicine, agriculture and catalyst for oxidation reactions. Taylor & Francis Group, LLC.
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Faith,Yantzi
, p. 1988 (1938)
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Hetero-mixed TiO2-SnO2 interfaced nano-oxide catalyst with enhanced activity for selective oxidation of furfural to maleic acid
Malibo, Petrus M.,Makgwane, Peter R.,Baker, Priscilla G.L.
, (2021)
Herein we report on the catalytic activity of hetero-mixed TiO2-SnO2 nano-oxide catalyst for the selective liquid-phase oxidation of furfural to maleic acid using H2O2 oxidant. The high surface area and strong interaction of the two oxides with modified electronic structure manifested enhanced effective oxygen vacancies, and redox activity performance of the TiO2-SnO2 catalyst for furfural oxidation reaction. The structure of the catalyst was investigated by the powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high-resolution transition electron microscopy (HRTEM), electron paramagnetic resonance (EPR) and Brunauer-Emmett-Teller (BET) surface area analyser techniques. The interfaced TiO2-SnO2 oxide catalyst was more catalytically active than its single counterpart SnO2 and TiO2 oxides to give a furfural conversion of 96.2% at up to 63.8% yield of maleic acid. The catalytic performance shown by TiO2-SnO2 present encouraging prospects for an economical solid metal oxide catalyst to access biobased maleic acid from renewable biomass-derived furfural.
In-situ fabrication of 0D/2D NiO/Bi12O17Cl2 heterojunction towards high-efficiency degrading 2, 4-dichlorophenol and mechanism insight
Song, Ning,Li, Jiaming,Li, Chunmei,Zhou, Pengjie,Jiang, Enhui,Zhang, Xiaoxu,Liu, Chunbo,Wu, Zhichen,Zheng, Hang,Che, Guangbo,Dong, Hongjun
, (2020)
2, 4-dichlorophenol (2, 4-DCP) as a persistent pollutant is frequently detected in water environments, complete eradication of trace which in water is an important task. Hence, a 0D/2D NiO/Bi12O17Cl2 heterojunction was achieved by in-situ fabrication of NiO nanodots on Bi12O17Cl2 nanosheets, which obviously improved the physical, optical and photoelectrochemical properties. The photocatalytic degradation activity of 0D/2D NiO/Bi12O17Cl2 heterojunction was boosted dramatically, which originated from the improved transfer and separation efficiency of charge carriers owing to the formation of Z-scheme heterostructure between NiO and Bi12O17Cl2. The possible photocatalytic reaction mechanism including migration behaviors of charge carriers, generation of reactive species and degradation intermediate products were revealed in depth. This work provides the valuable experiences for designing and fabricating otherwise 0D/2D heterojunction photocatalysts in the application of environmental treating fields.
Highly efficient formic acid-mediated oxidation of renewable furfural to maleic acid with H2O2
Li, Xiukai,Ho, Ben,Lim, Diane S. W.,Zhang, Yugen
, p. 914 - 918 (2017)
Maleic acid and its anhydride are important intermediates in the chemical industry produced on a multimillion tonne-scale annually. The synthesis of maleic acid/anhydride from renewable biomass resources such as furfural and 5-hydroxymethylfurfural is highly desirable for the sustainability of human society. Most of the previously reported processes for maleic acid/anhydride synthesis from biomass suffer from low efficiency, complicated conditions and poor catalyst recyclability. Herein, we demonstrate a highly efficient and simple system for the synthesis of maleic acid from furfural. An excellent yield (95%) of maleic acid was achieved under mild conditions in this very simple system which requires only H2O2 as an oxidant in formic acid solvent. Under similar conditions, an 89% yield of maleic acid was achieved from biomass-derived 5-hydroxymethylfurfural. This study presents a novel synthetic method and a promising process for maleic acid production from renewable biomass resources.
Degradation of chlorinated phenols in water in the presence of H 2O2 and water-soluble μ-nitrido diiron phthalocyanine
Colomban, Cédric,Kudrik, Evgeny V.,Afanasiev, Pavel,Sorokin, Alexander B.
, p. 14 - 19 (2014)
Efficient disposal of pollutants is a key problem in the environmental context. In particular, chlorinated aromatic compounds are recalcitrant to biodegradation and conventional treatment methods. Iron phthalocyanines were previously shown to be efficient catalysts for the oxidative degradation of chlorinated phenols considered as priority pollutants. We have recently discovered μ-nitrido diiron phthalocyanines as powerful oxidation catalysts. Herein, we evaluate these emerging catalysts in the oxidation of chlorinated phenols in comparison with conventional mononuclear complex. Catalytic performance of iron tetrasulfophthalocyanine (FePcS) and corresponding μ-nitrido dimer [(FePcS)2N] have been compared in the oxidation of chlorinated phenols by hydrogen peroxide in water. The oxidative degradation of 2,6-dichlorophenol (DCP) and 2,4,6-trichlorophenol (TCP) has been studied. The (FePcS)2N exhibited better catalytic properties than mononuclear FePcS in terms of conversion and mineralization (transformation of organic chlorine to Cl- and decrease of total organic carbon due to the formation of CO2). Kinetics of the DCP oxidation indicated that different reaction mechanisms are involved in the presence of FePcS and (FePcS)2N. The high catalytic activity of (FePcS)2N in the degradation and mineralization of chlorinated phenols make μ-nitrido diiron phthalocyanines promising catalyst to apply also in environmental remediation.
Remarkable Reactivity of Boron-Substituted Furans in the Diels-Alder Reactions with Maleic Anhydride
Medrán, Noelia S.,Dezotti, Federico,Pellegrinet, Silvina C.
, p. 5068 - 5072 (2019)
The reactivity of boron-substituted furans as dienes in the Diels-Alder reaction with maleic anhydride has been investigated. Gratifyingly, the furans with boryl substituents at C-3 gave the exo cycloadduct exclusively with excellent yields. In particular, the potassium trifluoroborate exhibited outstanding reactivity at room temperature. Theoretical calculations suggested that the trifluoroborate group is highly activating and also that the thermodynamics is the main factor that determines whether the products can be obtained efficiently or not.
Synthesis of maleic and fumaric acids from furfural in the presence of betaine hydrochloride and hydrogen peroxide
Araji,Madjinza,Chatel,Moores,Jér?me,De Oliveira Vigier
, p. 98 - 101 (2017)
Here we report the successful valorisation of furfural into maleic acid (MA) and fumaric acid (FA) with a total yield above 90% using an aqueous solution of betaine hydrochloride (BHC) in the presence of hydrogen peroxide. BHC can be recycled for at least 4 cycles and it can be used to directly convert xylose to MA and FA.
Effect of Al and Ce on Zr-pillared bentonite and their performance in catalytic oxidation of phenol
Mnasri-Ghnimi, Saida,Frini-Srasra, Najoua
, p. 1766 - 1773 (2016)
Catalysts based on pillared clays with Zr and/or Al and Ce–Zr and/or Al polycations have been synthesized from a Tunisian bentonite and tested in catalytic oxidation of phenol at 298 K. The Zr-pillared clay showed higher activity than the Al-one in phenol oxidation. Mixed Zr–Al pillars lead to an enhancement of the catalytic activity due to the modification of the zirconium properties. The clays modified with Ce showed high conversions of phenol and TOC thus showing to be very selective towards the formation of CO2 and H2O.
Facile preparation of a Ti/α-PbO2/β-PbO2 electrode for the electrochemical degradation of 2-chlorophenol
Zhang, Qianli,Guo, Xinyan,Cao, Xiaodan,Wang, Dongtian,Wei, Jie
, p. 975 - 981 (2015)
A Ti/α-PbO2/β-PbO2 electrode with high stability was prepared and examined toward the electrochemical degradation of 2-chlorophenol. Scanning electron microscopy analysis revealed that Ti/α-PbO2/β-PbO2 had a cauliflower morphology comprising small β-PbO2 crystals. The 2-chlorophenol removal rate using the Ti/α-PbO2/β-PbO2 electrode was 100% after 180 min of electrolysis under optimal conditions, which were selected based on the orthogonal test method, i.e., initial concentration of 2-cholorophenol = 50 mg/L, concentration of Na2SO4 = 0.1 mol/L, temperature = 35°C, and anode current density = 20 mA/cm2. Kinetic analyses demonstrated that the electrochemical oxidation of 2-chlorophenol on the Ti/α-PbO2/β-PbO2 electrode followed pseudo-first order kinetics.
Key role of the phosphate buffer in the H2O2 oxidation of aromatic pollutants catalyzed by iron tetrasulfophthalocyanine
Sanchez, Muriel,Hadasch, Anke,Fell, Rainer T.,Meunier, Bernard
, p. 177 - 186 (2001)
The non-innocent role of the phosphate buffer has been established in the H2O2 oxidative decomposition of 2,4,6-trichlorophenol (TCP), a benchmark pollutant, catalyzed by iron(III) tetrasulfophthalocyanine (FePcS). The catalytic oxidation of several other substrates (3,5-dichloroaniline, tetrachlorocatechol, di-tert-butylcatechol and catechol itself) has been carried out, also demonstrating a crucial influence of the phosphate buffer in the decomposition of the chlorinated substrates. Three hypotheses have been studied: modification of the ionic strength, formation of a peroxyphosphate species, or catalysis by a peroxyphosphate-FePcS complex. Supports for the latter proposal have been obtained from several experimental results and attempts have been made to characterize this putative catalytic intermediate. This intermediate derivative has also been generated from the reaction of FePcS with peroxymonophosphoric acid (PMPA) and its catalytic activity has been checked on the decomposition of TCP in different reaction mixture. A short mechanistic study has allowed different reaction pathways to be proposed, dependent on the active species implicated.
Catalyst for catalytic oxidation of furfural to prepare maleic acid and application thereof
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Page/Page column 10-12, (2022/02/10)
A catalyst for catalytic oxidation of furfural to prepare maleic acid, relating to the technical field of renewable energy. The catalyst is a mixture of a bromide and a base. A method for preparing the catalyst in catalytic oxidation of furfural to prepare maleic acid. The method includes: mixing the furfural, the bromide-base, an oxidant and a solvent to carry out a reaction to obtain the maleic acid. The present invention has the advantages that the method has a relatively high conversion rate of furfural and a relatively high yield of maleic acid, the conversion rate of furfural is up to 99%, the yield of maleic acid is up to 68.04%; and the catalyst has a high catalytic selectivity and reusability.
Electrochemical Strategy for the Simultaneous Production of Cyclohexanone and Benzoquinone by the Reaction of Phenol and Water
Wu, Ruizhi,Meng, Qinglei,Yan, Jiang,Liu, Huizhen,Zhu, Qinggong,Zheng, Lirong,Zhang, Jing,Han, Buxing
, p. 1556 - 1571 (2022/02/01)
Cyclohexanone and benzoquinone are important chemicals in chemical and manufacturing industries. The simultaneous production of cyclohexanone and benzoquinone by the reaction of phenol and water is an ideal route for the economical production of the two c
Parahydrogen-Induced Polarization Relayed via Proton Exchange
Them, Kolja,Ellermann, Frowin,Pravdivtsev, Andrey N.,Salnikov, Oleg G.,Skovpin, Ivan V.,Koptyug, Igor V.,Herges, Rainer,H?vener, Jan-Bernd
supporting information, p. 13694 - 13700 (2021/09/07)
The hyperpolarization of nuclear spins is a game-changing technology that enables hitherto inaccessible applications for magnetic resonance in chemistry and biomedicine. Despite significant advances and discoveries in the past, however, the quest to establish efficient and effective hyperpolarization methods continues. Here, we describe a new method that combines the advantages of direct parahydrogenation, high polarization (P), fast reaction, and low cost with the broad applicability of polarization transfer via proton exchange. We identified the system propargyl alcohol + pH2 → allyl alcohol to yield 1H polarization in excess of P ≈ 13% by using only 50% enriched pH2 at a pressure of ≈1 bar. The polarization was then successfully relayed via proton exchange from allyl alcohol to various target molecules. The polarizations of water and alcohols (as target molecules) approached P ≈ 1% even at high molar concentrations of 100 mM. Lactate, glucose, and pyruvic acid were also polarized, but to a lesser extent. Several potential improvements of the methodology are discussed. Thus, the parahydrogen-induced hyperpolarization relayed via proton exchange (PHIP-X) is a promising approach to polarize numerous molecules which participate in proton exchange and support new applications for magnetic resonance.