Xn:Harmful;
584-08-7Relevant articles and documents
Depolymerization of alkaline lignin over mesoporous KF/: γ -Al2O3
Guan, Yinshuang,Zhao, Wei,Liu, Kaishuai,Guo, Tiantian,Wang, Dingkai,Cui, Mingyu,Fu, Shuiyuan,Fan, Xing,Wei, Xianyong
, p. 14411 - 14420 (2020)
As a kind of biomass resource, lignin is the only natural renewable resource that can provide abundant aromatic compounds, which is undoubtedly considered as the best candidate to produce value-added chemicals by lignin depolymerization. Thus, it is of great significance to develop approaches that are able to accommodate the complex structure of lignin. Herein, an efficient depolymerization method is implemented in methanol using a mesoporous solid superbase KF/γ-Al2O3 catalyst. Research shows that the depolymerization of lignin is not obvious below the critical temperature of methanol, and the conversion of lignin increases significantly above the critical temperature, which can reach 60.6% at 270 °C. Phenols and methoxy-substituted monocyclic aromatic compounds are predominant in the liquid products acquired by gas chromatography/mass spectrometry. Furthermore, oligomers were analyzed by time-of-flight mass spectrometry equipped with electrospray ionization. It is found that the molecular mass of the oligomers varied between 200 and 600 Da, the degree of unsaturation is mainly 4 and 8 with 1-2 aromatic rings, and the carbon number is found to be within the range of 15-30. It is speculated that the oligomers are mainly monophenyl or biphenyl compounds containing branched chains.
New Phase Transition at 155 K and Thermal Stability in KHCO3
Lee, Kwang-Sei,Kim, Ill Won
, p. 3581 - 3584 (2001)
The differential scanning calorimetry and thermogravimetry of KHCO3 indicate new transformation anomalies at 155 K (Tc2), 373 K (Td) and 459 K. The former anomaly is likely to be caused by a structural phase transition, but the latter two anomalies are related to the thermal decomposition. The chemical reaction begins at about 373 K (Td) and reaches a complete thermal decomposition of KHCO3 into K2CO3 around 459 K. The experimental results are discussed in terms of protonic intrabond and interbond jump.
Characterization of zinc carbonate hydroxides synthesized by precipitation from zinc acetate and potassium carbonate solutions
Zhang,Fortier,Dahn
, p. 1939 - 1948 (2004)
Addition of potassium carbonate solution to zinc acetate solution at room temperature causes the precipitation of a white solid, whose composition and structure depend on the initial concentrations of the reagents. Hydrozincite, Zn5(CO3)2(OH)6, forms when the K2CO3 concentration is low and a new K-containing zinc carbonate hydroxide phase forms when the K2CO3 concentration is high. The chemical formula of the new phase has been determined to be Zn(CO3)0.61(OH)0.78·0.233K 2CO3 by TGA, CHNO and AA analysis. The new phase is insoluble in water and extensive water washing of the new phase does not change its composition or structure, suggesting the new phase is a single phase compound salt. Exposure of the new phase to a stream of humidified CO 2 causes disproportionation to separate phases of ZnCO3 and K2CO3. Pure ZnCO3 was synthesized for comparison by a new procedure under atmospheric conditions instead of the more common hydrothermal synthesis of ZnCO3.
Crystal structure dependent in vitro antioxidant activity of biocompatible calcium gallate MOFs
Hidalgo, Tania,Cooper, Lucy,Gorman, Martin,Lozano-Fernández, Tamara,Simón-Vázquez, Rosana,Mouchaham, Georges,Marrot, Jérome,Guillou, Nathalie,Serre, Christian,Fertey, Pierre,González-Fernández,Devic, Thomas,Horcajada, Patricia
, p. 2813 - 2822 (2017)
Two novel 3-D coordination polymers, denoted MIL-155 and MIL-156 (MIL stands for Materials Institute Lavoisier), built up from calcium and the naturally occurring gallic acid (H4gal), have been hydrothermally synthesized and their crystal struc
Characterization of paramagnetic KHo(WO4)2 nanocrystals: Synthesized by polymeric mixed-metal precursor sol-gel method
Thangaraju,Durairajan,Babu, S. Moorthy,Hayakawa
, p. 9890 - 9896 (2011)
Nanocrystalline KHo(WO4)2 (KHW) particles were successfully synthesized via conventional Pechini sol-gel method. Prepared precursor gel was calcined at 250, 550, 600, 650 and 700 °C, and the resulting samples were analyzed with TG-DTA, powder X-ray diffraction, FT-IR, Raman, FESEM, TEM, UV-Vis-NIR (diffuse reflectance spectrum (DRS)), fluorescence and vibrating sample magnetometer (VSM). Thermal degradation of derived gel was observed up to 400 °C and phase formation starts from 550 °C. The product phase formation at higher annealing temperature was investigated by means of powder XRD. Organic liberation in the samples with respect to temperature was analyzed using FT-IR spectrum. Raman spectrum reveals the formation of tungsten ribbons as well as the quality of the samples while increasing the calcination temperature. The nano size of the synthesized particles was confirmed with FESEM and TEM micrographs. Reflectance and emission studies reveal the corresponding absorption and emission properties of trivalent state holmium ion. Paramagnetic behavior of the derived KHW was confirmed with VSM results.
PROCESS FOR PRODUCING LACTATE
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Page/Page column 16, (2015/11/17)
A process for producing an alkali metal lactate comprising: a) reacting a stream rich in saccharide with barium hydroxide to produce a first reaction mixture comprising barium lactate; and b) contacting at least a portion of said first reaction mixture with an alkali metal hydroxide to produce a second reaction mixture comprising alkali metal lactate and solid barium hydroxide, wherein the alkali metal is selected from the group consisting of sodium, lithium and potassium.
New Complexes of Ruthenium, Method for Their Preparation, and Their Application in Olefin Metathesis Reactions
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Page/Page column, (2014/06/25)
The present invention provides new ruthenium complexes of Formula (1), which contain a chelate ring created by a halogen atom X. The invention concerns also a method for the preparation of the new ruthenium complexes and their application in metathesis reactions.
Nickel(i)-mediated transformations of carbon dioxide in closed synthetic cycles: Reductive cleavage and coupling of CO2 generating Ni ICO, NiIICO3 and NiIIC 2O4NiII en
Horn, Bettina,Limberg, Christian,Herwig, Christian,Braun, Beatrice
supporting information, p. 10923 - 10925 (2013/11/19)
The β-diketiminato nickel(i) complex K2[L tBuNiI(N22-)NiIL tBu] reacts with CO2via reductive disproportionation to form CO and CO32- containing p
Electrooxidation of ethylene glycol and glycerol on Pd-(Ni-Zn)/C anodes in direct alcohol fuel cells
Marchionni, Andrea,Bevilacqua, Manuela,Bianchini, Claudio,Chen, Yan-Xin,Filippi, Jonathan,Fornasiero, Paolo,Lavacchi, Alessandro,Miller, Hamish,Wang, Lianqin,Vizza, Francesco
, p. 518 - 528 (2013/06/05)
The electrooxidation of ethylene glycol (EG) and glycerol (G) has been studied: in alkaline media, in passive as well as active direct ethylene glycol fuel cells (DEGFCs), and in direct glycerol fuel cells (DGFCs) containing Pd-(Ni-Zn)/C as an anode electrocatalyst, that is, Pd nanoparticles supported on a Ni-Zn phase. For comparison, an anode electrocatalyst containing Pd nanoparticles (Pd/C) has been also investigated. The oxidation of EG and G has primarily been investigated in half cells. The results obtained have highlighted the excellent electrocatalytic activity of Pd-(Ni-Zn)/C in terms of peak current density, which is as high as 3300A g(Pd)-1 for EG and 2150A g(Pd)-1 for G. Membrane-electrode assemblies (MEA) have been fabricated using Pd-(Ni-Zn)/C anodes, proprietary Fe-Co/C cathodes, and Tokuyama A-201 anion-exchange membranes. The MEA performance has been evaluated in either passive or active cells fed with aqueous solutions of 5wt % EG and 5wt % G. In view of the peak-power densities obtained in the temperature range from 20 to 80 °C, at Pd loadings as low as 1mg cm -2 at the anode, these results show that Pd-(Ni-Zn)/C can be classified amongst the best performing electrocatalysts ever reported for EG and G oxidation. Copyright
Research and development of method for potassium acetate of high purity
Fakeev,Murskii,Krasil'Shchik
, p. 1807 - 1813 (2013/07/26)
Crystallization of potassium acetate from aqueous solutions, an effect of product yield and washing of its crystals on an efficiency of purification were investigated. Behavior of KCH3COO·1.5H2O was studied in heating. Based on data of the study a technological scheme of producing anhydrous potassium acetate of high purity was developed.
