Fractionation of Birch Wood by Integrating Alkaline-Acid Treatments and Hydrogenation in Ethanol over a Bifunctional Ruthenium Catalyst

For the first time, the fractionation of birch wood into microcrystalline cellulose, xylose and methoxyphenols is suggested based on the integration of alkali-acid pretreatments and hydrogenation in ethanol over a bifunctional Ru/C catalyst. It is established that removal of hemicelluloses during pretreatments of birch wood influences the yields of the liquid, gaseous and solid products of the non-catalytic and catalytic hydrogenation of pretreated samples in ethanol at 225 °C. The bifunctional Ru/carbon catalyst affects in different ways the conversion and yields of products of hydrogenation of the initial and acid- and alkali-pretreated birch wood. The most noticeable influence is characteristic of the hydrogenation of the acid-pretreated wood, where in contrast to the non-catalytic hydrogenation, the wood conversion and the yields of liquid products increase but the yields of the solid and gaseous products decrease. GC-MS, gel permeation chromatography and elemental analysis were used for characterization of the liquid product composition. The molecular mass distribution of the liquid products of hydrogenation of the initial and pretreated wood shifts towards the low-molecular range in the presence of the catalyst. From the GC-MS data, the contents of monomer compounds, predominantly 4-propylsyringol and 4-propanolsyringol, increase in the presence of the ruthenium catalyst. The solid products of catalytic hydrogenation of the pretreated wood contain up to 95 wt% of cellulose with the structure, similar to that of microcrystalline cellulose.

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HYDROGENATION OF ABIES WOOD AND ETHANOL-LIGNIN BY MOLECULAR HYDROGEN IN SUPERCRITI-CAL ETHANOL OVER BIFUNCTIONAL RU/C CATALYST

chemistry of plant raw material ◽

10.14258/jcprm.2019025108 ◽

2019 ◽

pp. 15-26 ◽

Cited By ~ 1

Author(s):

Aleksandr Sergeyevich Kazachenko ◽

Sergey Viktorovich Baryshnikov ◽

Anna Il'inichna Chudina ◽

Yuriy Nikolayevich Malyar ◽

Valentin Vladimirovich Sychev ◽

...

Keyword(s):

Molecular Mass ◽

Liquid Product ◽

Carbon Support ◽

Bifunctional Catalyst ◽

Ruthenium Catalyst ◽

Solid Residue ◽

Average Molecular Mass ◽

Gaseous Products ◽

Liquid Products ◽

Oxidized Carbon

The effect of a bifunctional catalyst containing nano-dispersed ruthenium particles on an oxidized carbon support “Sibunit” on the yield and composition of products in the processes of hydrogenation of abies wood and abies ethanol-lignin in a supercritical ethanol medium at 250° C was studied. The presence of Ru/C catalyst resulted in a raise the ethanol-lignin conversion from 85 to 98 wt.%, the yield of liquid product from 75 to 85 wt.%, the yield of gases – by 1.5 times, but the yield of solid products dropped from 14 to 2.8 wt.%. Ruthenium catalyst increased the conversion of abies wood by 12.5 wt.%, but did not affect the yield of liquid products. The yield of the solid residue in the presence of the catalyst was reduced by 12.5 wt.%, and the yield of gases rose by 2.5 times. Simultaneously, the ruthenium catalyst promoted the process of hydrodeoxygenation of liquid products, diminution their average molecular mass from 1174 g/mol to 827 g/mol and the formation of monomeric and dimeric compounds with a molecular mass 193 and 426 g/mol, respectively. The solid residue of catalytic hydrogenation contained 70.1 wt.% of cellulose. Thus, the application of Ru/C catalyst in the process of hydrogenation of abies wood allowed the reductive fractionation of wood biomass into a solid cellulose product, liquid and gaseous products from lignin and hemicelluloses.

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Karakterisasi dan Aplikasi Katalis Nikel-Molibdenum Teremban pada Zeolit Alam Aktif untuk Hidrorengkah Tir Batubara

Jurnal Natur Indonesia ◽

10.31258/jnat.16.1.10-22 ◽

2015 ◽

Vol 16 (1) ◽

pp. 10

Author(s):

Dwi Julian Sugianto ◽

Karna Wijaya ◽

Iqmal Tahir

Keyword(s):

Natural Zeolite ◽

Coal Tar ◽

Liquid Product ◽

Total Pore Volume ◽

Optimum Temperature ◽

Total Conversion ◽

Wet Impregnation ◽

Liquid Products ◽

Molybdenum Catalysts

Preparation and characterization of nickel-molybdenum catalysts supported on activated natural zeolite over hydrorackingof coal tar have been done. Modification of catalyst was included activation of zeolite by HCl 6N, wet impregnation of Ni-Mo metal and leaching the Ni-Mo from zeolite surfaces with EDTA solution.The parameters of catalyst have been determinedi.e acid site number, the ratio of Si/Al, crystallinity, content of Ni-Mo metal, specific surface area, total pore volume, and poreaverage diameter. The hydrocracking of coal tar was carried out at the optimum temperature (450°C) by flowing H2 gas (flowrate of 20 mL/min) on the coal tar with ratio of feed:catalyst was 10:1. The resulting liquid product was analyzed by GC/GCMS.The result showed that catalytic hydrocracking with ZAA catalyst had the highest conversion of liquid products,which were 40.51% (w/w) compared to Ni-Mo/ZAA catalyst gave 28.61% and Ni-Mo/ZAA(E) gaves 28.06% (w/w). Thehighest light fractions (67.63% (w/w)) produced by using Ni-Mo/ZAA catalyst and the highest medium fractions wereproduced over ZAA catalyst which was 36.61% (w/w) and the highest total conversion on the product with Ni-Mo/ZAA(E)catalyst produced was 50.05% (w/w). The product analyzed with GC-MS result on the 9th highest peak showed that thehydrocracking products resulted over Ni-Mo/ZAA mostly were phenol and its derivatives.

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Investigation on pyrolysis of some organic raw materials

Mongolian Journal of Chemistry ◽

10.5564/mjc.v17i43.739 ◽

2017 ◽

Vol 17 (43) ◽

pp. 5-13

Author(s):

Purevsuren B ◽

Davaajav Ya ◽

Batbileg S ◽

Ariunaa A ◽

Namkhainorov J ◽

...

Keyword(s):

Thermal Stability ◽

Epoxy Resin ◽

Raw Materials ◽

Gaseous Products ◽

Animal Bone ◽

Waste Milk ◽

Heavy Fractions ◽

Milk Casein ◽

First Time

We have been working on pyrolysis of some organic raw materials including different rank coals, oil shale, wood waste, animal bone, cedar shell, polypropylene waste, milk casein and characterization of obtained hard residue, tar and pyrolytic water and gas after pyrolysis. The technical characteristics of these organic raw materials have been determined and the thermal stability characteristics such as thermal stability indices (T5% and T25%) determined by using thermogravimetric analysis. The pyrolysis experiments were performed at different heating temperatures and the yields of hard residue, tar, pyrolysis water and gaseous products were determined and discussed. The main technical characteristics of hard residue of organic raw materials after pyrolysis have been determined and the adsorption ability of pyrolysis hard residue and its activated carbon of organic raw materials also determined. The pyrolysis tars of organic raw materials were distilled in air condition and determined the yields of obtained light, middle and heavy fractions and bitumen like residue with different boiling temperature. This is the first time to investigate the curing ability of pyrolysis tars of organic raw materials for epoxy resin and the results of these experiments showed that only tar of milk casein has the highest (95.0%), tar of animal bone has certain (18.70%) and tars of all other organic raw materials have no curing ability for epoxy resin.

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Pyrolysis of Table Sugar

The Scientific World JOURNAL ◽

10.1155/2013/172039 ◽

2013 ◽

Vol 2013 ◽

pp. 1-3

Author(s):

Adnan Bulut ◽

Selhan Karagöz

Keyword(s):

Pyrolysis Temperature ◽

Relative Concentration ◽

Fixed Bed ◽

Liquid Product ◽

Fixed Bed Reactor ◽

Gas Chromatography Mass Spectrometry ◽

Gaseous Products ◽

Hydroxymethyl Furfural ◽

Liquid Products ◽

Different Temperatures

Table sugars were pyrolyzed at different temperatures (300, 400, and 500°C) in a fixed-bed reactor. The effect of pyrolysis temperature on yields of liquid, solid, and gaseous products was investigated. As expected the yield of liquid products gradually increased and the yield of solid products gradually decreased when the pyrolysis temperature was raised. The yield of liquid products was greatest (52 wt%) at 500°C. The composition of bio-oils extracted with diethyl ether was identified by means of gas chromatography mass spectrometry (GC-MS), nuclear magnetic resonance (1H-NMR), and Fourier transform infrared spectroscopy (FTIR). The following compounds were observed in bio-oils produced from the pyrolysis of table sugar at 500°C: 1,4:3,6-dianhydro-α-d-glucopyranose, 5-(hydroxymethyl) furfural, 5-acetoxymethyl-2-furaldehyde, and cyclotetradecane liquid product. The relative concentration of 5-(hydroxymethyl) furfural was the highest in bio-oils obtained from pyrolysis of table sugars at 500°C.

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Hydrogenation of Abies Wood and Ethanol Lignin by Hydrogen in Supercritical Ethanol in the Presence of Bifunctional Catalyst Pt/ZrO₂

Journal of Siberian Federal University Chemistry ◽

10.17516/1998-2836-0150 ◽

2019 ◽

pp. 550-561

Author(s):

Sergei V. Baryshnikov ◽

Angelina V. Miroshnikova ◽

Alexandr S. Kazachenko ◽

Yuriy N. Malyar ◽

Oxana P. Taran ◽

...

Keyword(s):

Catalytic Hydrogenation ◽

Bifunctional Catalyst ◽

Cellulose Content ◽

Solid Residue ◽

Wood Biomass ◽

Solid Product ◽

Gaseous Products ◽

Liquid Products ◽

Supercritical Ethanol ◽

Composition Of Products

The effect of bifunctional catalyst Pt/ZrO₂ on the yield and composition of products of abies wood and ethanol lignin hydrogenation in supercritical ethanol at temperature of 250 °C was established. In the process of abies wood hydrogenation, the catalyst Pt/ZrO₂ increases the degree of conversion of wood from 52.0 to 65.7 wt.%, the yield of liquid products from 31.0 to 38.1 wt.%,.%, and also increases the content of monomeric compounds in the liquid products. In the presence of catalyst, the cellulose content in the solid product of wood catalytic hydrogenation reaches to 77.1 wt.%, and the content of lignin and hemicelluloses decreases to 21.2 wt.% and 1.7 wt.%, respectively. In the process of ethanol lignin hydrogenation the catalyst Pt/ZrO₂ increases the degree of lignin conversion from 86.0 to 99.4 wt.%, the yield of liquid products from 75.0 to 90.0 wt.%, and also reduces the yield of solid residue from 14.0 to 0.6 wt.% and the yield of gases from 4.7 to 3.3 wt.%. Thus, the polysaccharides of wood biomass complicate the reductive depolymerization of native lignin in comparison with the depolymerization of isolated ethanol lignin. The use of the catalyst Pt/ZrO₂ makes it possible to fractionate the abies wood in supercritical ethanol at 250 °C on solid product with a high content of cellulose, as well as liquid and gaseous products from lignin and hemicelluloses

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Thermal processing of Khoot coal and characterization of obtained solid and liquid products

Mongolian Journal of Chemistry ◽

10.5564/mjc.v15i0.326 ◽

2014 ◽

Vol 15 ◽

pp. 66-72

Author(s):

S Batbileg ◽

B Purevsuren ◽

Ya Davaajav ◽

J Namkhainorov

Keyword(s):

Activated Carbon ◽

Liquid Product ◽

Sem Analysis ◽

Spectrometric Analysis ◽

Water Steam ◽

Initial Coal ◽

Thermal Dissolution ◽

Liquid Products ◽

Ir Analysis

On 21st January 2015, the abstract of this paper was replaced with the correct abstract.The coal of Khoot deposit have been investigated and determined the technical characteristics, elemental and petrographical maceral compositions. On the basis of proximate, ultimate, petrographic and IR analysis results have been confirmed that the Khoot coal is a sub-bituminous coal. The hard residue after pyrolysis have been activated by heated water steam and determined the iodine and methylene blue adsorption of initial coal and activated carbon samples from pyrolysis hard residue. The porosity structure of initial coal, activated carbon of pyrolysis hard residue and hard residue after thermolysis (thermal dissolution) have been determined by SEM analysis. The liquid tar product of thermolysis of Khoot coal was investigated by FTIR, 13C and 1H NMR spectrometric analysis. The results of thermolysis of Khoot coal in tetralin with constant mass ratio between coal and tetralin (1:1.8) at 450°C show that 60.8% of liquid product can be obtained after thermolysis of the coal organic mass.DOI: http://doi.dx.org/10.5564/mjc.v15i0.326 Mongolian Journal of Chemistry 15 (41), 2014, p66-72

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TBE in Sweden

Tick-borne encephalitis - The Book ◽

10.33442/26613980_12b32-3 ◽

2020 ◽

Keyword(s):

Genetic Characterization ◽

Immunoglobulin M ◽

Enzyme Linked Immunosorbent Assay ◽

Second Phase ◽

Serum Samples ◽

Tick Borne Encephalitis ◽

Specific Immunoglobulin ◽

Tick Borne Encephalitis Virus ◽

First Time

Tick-borne encephalitis virus (TBEV) was isolated for the first time in Sweden in 1958 (from ticks and from 1 tick-borne encephalitis [TBE] patient).1 In 2003, Haglund and colleagues reported the isolation and antigenic and genetic characterization of 14 TBEV strains from Swedish patients (samples collected 1991–1994).2 The first serum sample, from which TBEV was isolated, was obtained 2–10 days after onset of disease and found to be negative for anti-TBEV immunoglobulin M (IgM) by enzyme-linked immunosorbent assay (ELISA), whereas TBEV-specific IgM (and TBEV-specific immunoglobulin G/cerebrospinal fluid [IgG/CSF] activity) was demonstrated in later serum samples taken during the second phase of the disease.

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Study of the Kinetics of Thermal Destruction of Crossed Polyethylene

Bulletin of Science and Practice ◽

10.33619/2414-2948/49/04 ◽

2019 ◽

Vol 5 (12) ◽

pp. 37-46

Author(s):

K. Chalov ◽

Yu. Lugovoy ◽

Yu. Kosivtsov ◽

E. Sulman

Keyword(s):

Total Yield ◽

Calorific Value ◽

High Heat ◽

Process Temperature ◽

Optimum Process ◽

Quantitative Composition ◽

Pyrolysis Gas ◽

Gaseous Products ◽

Liquid Products ◽

Kinetics Of

This paper presents a study of the process of thermal degradation of crosslinked polyethylene. The kinetics of polymer decomposition was studied by thermogravimetry. Crosslinked polyethylene showed high heat resistance to temperatures of 400 °C. The temperature range of 430–500 °C was determined for the loss of the bulk of the sample. According to thermogravimetric data, the decomposition process proceeds in a single stage and includes a large number of fracture, cyclization, dehydrogenation, and other reactions. The process of pyrolysis of a crosslinked polymer in a stationary-bed metal reactor was investigated. The influence of the process temperature on the yield of solid, liquid, and gaseous pyrolysis products was investigated. The optimum process temperature was 500 °C. At this temperature, the yield of liquid and gaseous products was 85.0 and 12.5% (mass.), Respectively. Samples of crosslinked polyester decomposed almost completely. The amount of carbon–containing residue was 3.5% by weight of the feedstock. With increasing temperature, the yield of liquid products decreased slightly and the yield of gaseous products increased, but their total yield did not increase. For gaseous products, a qualitative and quantitative composition was determined. The main components of the pyrolysis gas were hydrocarbons C1–C4. The calorific value of pyrolysis gas obtained at a temperature of 500 °C was 17 MJ/m3. Thus, the pyrolysis process can be used to process crosslinked polyethylene wastes to produce liquid hydrocarbons and combustible gases.

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Chemical Constituents and Antibacterial Activity of Cissus Aralioides.

Letters in Organic Chemistry ◽

10.2174/1570178617999200609130127 ◽

2020 ◽

Vol 17 ◽

Author(s):

Balogun Olaoye Solomon ◽

Ajayi Olukayode Solomon ◽

Owolabi Temitayo Abidemi ◽

Oladimeji Abdulkarbir Oladele ◽

Liu Zhiqiang

Keyword(s):

Plant Extract ◽

Chemical Constituents ◽

Ethyl Acetate Fraction ◽

Antibacterial Activities ◽

Sub Saharan Africa ◽

Chromatographic Purification ◽

Whole Plant ◽

Sub Saharan ◽

First Time

: Cissus aralioides is a medicinal plant used in sub-Saharan Africa for treatment of infectious diseases; however the chemical constituents of the plant have not been investigated. Thus, in this study, attempt was made at identifying predominant phytochemical constituents of the plant through chromatographic purification and silylation of the plant extract, and subsequent characterization using spectroscopic and GC-MS techniques. The minimum inhibitory concentration (MICs) for the antibacterial activities of the plant extract, chromatographic fractions and isolated compounds were also examined. Chromatographic purification of the ethyl acetate fraction from the whole plant afforded three compounds: β-sitosterol (1), stigmasterol (2) and friedelin (3). The phytosterols (1 and 2) were obtained together as a mixture. The GC-MS analysis of silylated extract indicated alcohols, fatty acids and sugars as predominant classes, with composition of 24.62, 36.90 and 26.52% respectively. Results of MICs indicated that friedelin and other chromatographic fractions had values (0.0626-1.0 mg/mL) comparable with the standard antibiotics used. Characterization of natural products from C. aralioides is being reported for the first time in this study.

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Green Synthesis and Spectroscopic Studies of Ag-rGO Nanocomposites for Highly Selective Mercury (II) Sensing

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681207666170705143629 ◽

2018 ◽

Vol 9 (1) ◽

pp. 101-108 ◽

Cited By ~ 1

Author(s):

Shubhangi J. Mane-Gavade ◽

Sandip R. Sabale ◽

Xiao-Ying Yu ◽

Gurunath H. Nikam ◽

Bhaskar V. Tamhankar

Keyword(s):

Green Synthesis ◽

Color Change ◽

Limit Of Detection ◽

Aqueous Media ◽

Suitable Condition ◽

Cost Effective ◽

Spectroscopic Studies ◽

Calibration Plot ◽

First Time

Introduction: Herein we report the green synthesis and characterization of silverreduced graphene oxide nanocomposites (Ag-rGO) using Acacia nilotica gum for the first time. Experimental: We demonstrate the Hg2+ ions sensing ability of the Ag-rGO nanocomposites form aqueous medium. The developed colorimetric sensor method is simple, fast and selective for the detection of Hg2+ ions in aqueous media in presence of other associated ions. A significant color change was noticed with naked eye upon Hg2+ addition. The color change was not observed for cations including Sr2+, Ni2+, Cd2+, Pb2+, Mg2+, Ca2+, Fe2+, Ba2+ and Mn2+indicating that only Hg2+ shows a strong interaction with Ag-rGO nanocomposites. Under the most suitable condition, the calibration plot (A0-A) against concentration of Hg2+ was linear in the range of 0.1-1.0 ppm with a correlation coefficient (R2) value 0.9998. Results & Conclusion The concentration of Hg2+ was quantitatively determined with the Limit of Detection (LOD) of 0.85 ppm. Also, this method shows excellent selectivity towards Hg2+ over nine other cations tested. Moreover, the method offers a new cost effective, rapid and simple approach for the detection of Hg2+ in water samples.

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