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

2019 ◽  
pp. 15-26 ◽  
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.

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

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1362
Author(s):  
Boris N. Kuznetsov ◽  
Sergey V. Baryshnikov ◽  
Angelina V. Miroshnikova ◽  
Aleksandr S. Kazachenko ◽  
Yuriy N. Malyar ◽  
...  
Keyword(s):  
Microcrystalline Cellulose ◽  
Catalytic Hydrogenation ◽  
Liquid Product ◽  
Gel Permeation Chromatography ◽  
Ruthenium Catalyst ◽  
Birch Wood ◽  
Gaseous Products ◽  
Liquid Products ◽  
First Time

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.

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

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

scholarly journals Pyrolysis of Table Sugar

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.

scholarly journals Reductive Catalytic Fractionation of Flax Shive over Ru/C Catalysts

Catalysts ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 42
Author(s):  
Aleksandr S. Kazachenko ◽  
Valery E. Tarabanko ◽  
Angelina V. Miroshnikova ◽  
Valentin V. Sychev ◽  
Andrey M. Skripnikov ◽  
...  
Keyword(s):  
Elevated Temperatures ◽  
Carbon Support ◽  
Bifunctional Catalyst ◽  
Bifunctional Catalysts ◽  
Cellulose Content ◽  
Lignin Fraction ◽  
Liquid Products ◽  
Different Characteristics ◽  
High Degree ◽  
High Cellulose

Flax shive is the main waste (up to 70 wt %) in the production of flax fiber. It represents the lignified parts of the flax stem mainly in the form of small straws. Complex processing of such wastes is a significant problem due to the heterogeneity of the chemical structure of lignin. This article presents the results of reductive catalytic fractionation (RCF) of flax shive in ethanol and isopropanol at elevated temperatures (225–250 °C) in the presence of a bifunctional catalyst (Ru/C) and molecular hydrogen. This provides solvolytic depolymerization of lignin and hemicelluloses presented in flax shive. Catalytic hydrogenation effectively stabilizes the formed lignin intermediates and prevents repolymerization reactions producing the lignin fraction with a high degree of depolymerization. RCF of flax shive produces solid products with a high cellulose content and liquid products consisting mainly of monophenolic compounds. Furthermore, the effect of different characteristics (the ruthenium content, particle size, and support acidity) of the bifunctional catalysts containing ruthenium nanoparticles supported on mesoporous, graphite-like carbon material Sibunit®-4 on the yield and composition of the products of hydrogenation of flax shive in sub- and super-critical ethanol has been studied. Bifunctional catalysts Ru/C used in the RCF of flax shive increase its conversion from 44 to 56 wt % and the yield of monophenols from 1.1 to 10.2 wt % (based on the weight of lignin in the sample). Using the best Ru/C catalyst containing 3% of Ru on oxidized at 400 °C carbon support, the high degree of delignification (up to 79.0%), cellulose yield (up to 67.2 wt %), and monophenols yield (up to 9.5 wt %) have been obtained.

Study of the Kinetics of Thermal Destruction of Crossed Polyethylene

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.

MANUFACTURING GASEOUS PRODUCTS BY PYROLYSIS MICROALGAE BIOMASS

2019 ◽  
pp. 23-34
Author(s):  
N. I. Chernova ◽  
S. V. Kiseleva ◽  
O. M. Larina ◽  
G. A. Sytchev
Keyword(s):  
Raw Materials ◽  
Renewable Energy Sources ◽  
High Energy ◽  
Initial Mass ◽  
Solid Residue ◽  
Algae Biomass ◽  
Gaseous Products ◽  
Microalgae Biomass ◽  
Pyrolysis Liquid ◽  
Pyrolysis Gases

Algae biomass is considered as an alternative raw material for the production of biofuels. The search for new types of raw materials, including high-energy types of microalgae, remains relevant, since the share of motor fuels in the structure of the global fuel and energy balance remains consistently high (about 35%), and the price of oil is characterized by high volatility. The authors have considered the advantages of microalgae as sources of raw materials for fuel production. Biochemical and thermochemical conversion are proposed as technologies for their processing. This paper presents the results of the study of the pyrolysis of the biomass of clonal culture of blue-green microalgae / cyanobacteriumArthrospira platensis rsemsu 1/02-Pfrom the collection of the Research Laboratory of Renewable Energy Sources of the Lomonosov Moscow State University. An experiment to study the process of pyrolysis of microalgae biomass was carried out at the experimental facility of the Institute of High Temperatures RAS in pure nitrogen grade 6.0 to create an oxygen-free environment with a linear heating rate of 10 ºС / min from room temperature to 1000 ºС. The whole process of pyrolysis proceeded in the field of endothermy. The specific amounts of solid residue, pyrolysis liquid and gaseous products were experimentally determined. As a result of the pyrolysis of microalgae biomass weighing 15 g, the following products were obtained: 1) coal has the mass of the solid residue is 2.68 g, or 17.7% of the initial mass of the microalgae (while 9.3% of the initial mass of the microalgae remained in the reactor); 2) pyrolysis liquid – weight 3.3 g, or 21.9% of the initial weight; 3) non-condensable pyrolysis gases – weight 1.15 l. The specific volumetric gas yield (the amount of gas released from 1 kg of the starting material) was 0.076 Nm3/ kg. The analysis of the composition and specific volume yield of non-condensable pyrolysis gases formed in the process of pyrolysis, depending on temperature. It is shown that with increasing temperature, the proportion of highcalorie components of the gas mixture (hydrogen, methane and carbon monoxide) increases. The calorific value of the mixture of these gases has been estimated.

Extraction of polyethylene glycols with dicarbolide solutions in nitrobenzene

1990 ◽  
Vol 55 (8) ◽  
pp. 1959-1967 ◽  
Author(s):  
Petr Vaňura ◽  
Pavel Selucký
Keyword(s):  
Polyethylene Glycol ◽  
Molecular Mass ◽  
Extraction Constant ◽  
Metal Extraction ◽  
Polyethylene Glycols ◽  
Relative Molecular Mass ◽  
Published Data ◽  
Average Molecular Mass ◽  
Peg 400 ◽  
Extraction Constants

The extraction of polyethylene glycol of average molecular mass 400 (PEG 400) with dicarbolide solution in nitrobenzene and of longer-chain polyethylene glycol, of average molecular mass 1 500 (PEG 1 500), with chlorinated dicarbolide solution in nitrobenzene was studied. During the extraction of PEG 400, the polyethylene glycol solvates the Horg+ ion in the organic phase giving rise to the HLorg+ species (L is polyethylene glycol). The obtained value of the extraction constant Kex(HLorg+) = 933 is consistent with published data of metal extraction. Extraction of PEG 1 500 was treated applying the simplified assumption that the thermodynamic behaviour of PEG 1 500 is the same as that of n molecules of polyethylene glycol with relative molecular mass 1 500/n, each solvating one cation. For this model, the value of n = 3.2 ± 1.1 and the values of the extraction constants of the HL1/n,org+ and HL2/n,org+ species were obtained by using the adapted program LETAGROP. This value of n is consistent with published extraction data in the presence of polyethylene glycol with a relative molecular mass from 200 to 1 000.

scholarly journals Nanomechanical Molecular Mass Sensing Using Suspended Microchannel Resonators

Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3337
Author(s):  
Alberto Martín-Pérez ◽  
Daniel Ramos ◽  
Javier Tamayo ◽  
Montserrat Calleja
Keyword(s):  
Molecular Mass ◽  
Mass Density ◽  
Applied Pressure ◽  
Atomic Mass ◽  
Liquid Sample ◽  
Mass Sensing ◽  
Average Molecular Mass ◽  
Fluid Properties ◽  
Molecular Masses ◽  
Microchannel Resonators

In this work we study the different phenomena taking place when a hydrostatic pressure is applied in the inner fluid of a suspended microchannel resonator. Additionally to pressure-induced stiffness terms, we have theoretically predicted and experimentally demonstrated that the pressure also induces mass effects which depend on both the applied pressure and the fluid properties. We have used these phenomena to characterize the frequency response of the device as a function of the fluid compressibility and molecular masses of different fluids ranging from liquids to gases. The proposed device in this work can measure the mass density of an unknown liquid sample with a resolution of 0.7 µg/mL and perform gas mixtures characterization by measuring its average molecular mass with a resolution of 0.01 atomic mass units.

scholarly journals Valuable Chemicals Derived from Pyrolysis Liquid Products of Spirulina platensis Residue

2019 ◽  
Vol 19 (3) ◽  
pp. 703 ◽  
Author(s):  
Siti Jamilatun ◽  
Budhijanto Budhijanto ◽  
Rochmadi Rochmadi ◽  
Avido Yuliestyan ◽  
Arief Budiman
Keyword(s):  
Polyaromatic Hydrocarbons ◽  
Food Additives ◽  
Fixed Bed ◽  
Liquid Product ◽  
Fixed Bed Reactor ◽  
Water Phase ◽  
Gas Chromatography Mass Spectrometry ◽  
Human Needs ◽  
Liquid Products ◽  
Interesting Alternative

With a motto of preserving nature, the use of renewable resources for the fulfillment of human needs has been seen echoing these days. In response, microalgae, a water-living microorganism, is perceived as an interesting alternative due to its easy-to-cultivate nature. One of the microalgae, which possess the potential for being the future source of energy, food, and health, is Spirulina plantesis. Aiming to identify valuable chemicals possibly derived from it, catalytic and non-catalytic pyrolysis process of the residue of S. plantesis microalgae has been firstly carried out in a fixed-bed reactor over the various temperature of 300, 400, 500, 550 and 600 °C. The resulting vapor was condensed so that the liquid product consisting of the top product (oil phase) and the bottom product (water phase) can be separated. The composition of each product was then analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). In the oil phase yield, the increase of aliphatic and polyaromatic hydrocarbons (PAHs) and the decrease of the oxygenated have been observed along with the increase of pyrolysis temperature, which might be useful for fuel application. Interestingly, their water phase composition also presents some potential chemicals, able to be used as antioxidants, vitamins and food additives.

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