Non-Catalytic Dissolution of Biochar Obtained by Hydrothermal Carbonization of Sawdust in Hydrogen Donor Solvent

The production of fuel hydrocarbons from CO2-neutral raw materials is a promising task at present. The thermal dissolution of biochar obtained by the method of hydrothermal carbonization of sawdust was studied. The dissolution of biochar in tetralin (hydrogen donor solvent) was studied at different temperatures (350–450 °C) and with two types of dilution of the mixture with tetralin: 1/3 and 1/4. The process proceeded without a catalyst. It was found that the samples subjected to thermal dissolution at temperatures of 425–450 °C had the highest conversion and yield of liquid products. The reaction temperature also had a significant effect on the composition of liquid products. It was found that an increase in the reaction temperature led to a significant increase in benzenes, both in the direct and in the hexane fraction. A benzene yield of more than 50% was observed for both fractions at a temperature of 450 °C. It was also suggested that the possible positive effect of abietates on the homogenization of the reaction mixture contributed to high conversion in the process. The biochar/tetralin ratio effects the yield and composition of the liquid products as well. An increase in the tetralin concentration in the mixture during thermal dissolution led to an increase in the conversion and yield of hydrocarbon fractions for fuel purposes. This is undoubtedly due to the large amount of elemental hydrogen involved in the hydrogenation of the reaction mixture.

Download Full-text

Catalytic Thermal Liquefaction of Oil Shale in Tetralin

ISRN Chemical Engineering ◽

10.5402/2012/617363 ◽

2012 ◽

Vol 2012 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

I. Johannes ◽

L. Tiikma ◽

H. Luik ◽

H. Tamvelius ◽

J. Krasulina

Keyword(s):

Oil Shale ◽

Pyrolysis Temperature ◽

Short Review ◽

Experimental Results ◽

Hydrogen Donor ◽

Solid Fuels ◽

Thermal Dissolution ◽

Donor Solvent ◽

Catalyst Type

A short review on the publications concerning thermal liquefaction of solid fuels in the environment of hydrogen donor solvents and catalysts is compiled. New experimental results on the catalytic thermal dissolution of oil shale in tetralin as the hydrogen donor solvent in a batch autoclave are presented. The impacts of pyrolysis temperature, duration, and catalyst type on the yields of gas, maltenes, asphaltenes, preasphaltenes, and coke in the presence of tetralin are described.

Download Full-text

Investigation of the activity catalytic system of the Pr/NH4(ZSM) in the conversion of n-hexane

Butlerov Communications ◽

10.37952/roi-jbc-01/19-57-1-57 ◽

2019 ◽

Vol 57 (1) ◽

pp. 57-61

Author(s):

Vladimir A. Silaev ◽

◽

Elshad Afsar ogly Gadirov ◽

Maxim O. Taraskin ◽

Nina I. Komarova ◽

...

Keyword(s):

Catalytic System ◽

Raw Materials ◽

Gas Liquid Chromatography ◽

Impregnation Method ◽

Environmental Standards ◽

Oil Reserves ◽

Motor Fuels ◽

Liquid Products ◽

Different Temperatures ◽

High Octane

Due to the rapid growth of consumption of high-quality, environmentally friendly motor fuels and the exhaustion of oil reserves, the modernization of existing technologies and processes for the production of high-octane gasoline remains relevant. One of these processes, which allows to obtain fuels that meet environmental standards, is the process of catalytic reforming. This work is devoted to the study of the activity of the pure carrier – NH4(ZSM) and the catalytic system Pr/NH4(ZSM) (the amount of praseodymium is 0.7% wt.) prepared by the impregnation method based on pure zeolite NH4(ZSM) (n-hexane transformation). The analysis of the obtained conversion products was performed by gas-liquid chromatography. The activity of the catalyst was evaluated according to parameters such as the degree of conversion of raw materials, the selectivity of the formation of products. On the basis of experimental data, it was shown that when n-hexane is converted on a catalyst in an air flow, high-octane components of the fuel can be obtained. As a result of systematic studies of pure NH4(ZSM), it was shown that with an increase in temperature, the conversion of n-hexane to 99.6% at a temperature of 500 ºС increases. The introduction of praseodymium into the catalyst leads to a redistribution of the number of acid and metal reaction centers, which is accompanied by a maximum conversion rate of 99.5% at a temperature of 350 ºС, an increase in the proportion of aromatic and gaseous compounds in the conversion products. As a result of the conversion of n-hexane on the two systems, valuable gaseous and liquid products were obtained. All liquid products obtained at different temperatures have large octane number values, which is explained by the high content of isomer products at low temperatures of the experiment and aromatic products at high temperatures of the experiment.

Download Full-text

Greener Solution to Waste Corn Stalks and Shortage of Asphalt Resource: Hydrochar Produced by Hydrothermal Carbonization as a Novel Performance Enhancer for Asphalt Binder

Materials ◽

10.3390/ma14061427 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1427

Author(s):

Xiaoming Wu ◽

Chichun Hu

Keyword(s):

High Temperature ◽

Reaction Temperature ◽

Storage Stability ◽

Asphalt Binder ◽

Aging Effect ◽

Experimental Tests ◽

Hydrothermal Carbonization ◽

Modified Asphalt ◽

Direct Combustion ◽

Aging Property

Utilization of waste corn stalks (CS) has seized extensive attention due to high annual output and hazardous impact of piling aside or direct combustion on environment. However, previously there has been a lot of emphasis on improvement of its energy efficiency as solid fuel while limited investigations are available which explore the possibility of applying corn stalks as performance enhancer in asphalt binder. The purpose of this study is to examine the potential of employing hydrochar as modifiers in asphalt binder by a series of experimental tests. In this study, two hydrochar were produced from corn stalks by a novel process called hydrothermal carbonization at a different reaction temperature. The two hydrochar and their responding hydrochar-modified asphalt (HCMA) were tested by chemical and rheological tests. Chemical analysis detected the interaction between hydrochar and binder factions, resulting in poor compatibility but satisfying anti-aging property. Even though hydrochar increased the viscosity of bitumen, implying worse workability, and caused poor storage stability, ameliorated performance of asphalt binder at high temperature by incorporating hydrochar was verified by various criteria such as higher performance grade (PG) failure temperature and lower non-recoverable creep compliance (Jnr). Moreover, higher reaction temperature makes hydrochar’s particles smaller and more homogeneous, which results in slightly lower enhanced high temperature performance, more satisfying workability, better storage stability, and greater anti-aging effect of hydrochar-modified asphalt. Eventually, this study provided a promising win-win solution to environment problems concerning corn stalk treatment and shortage of asphalt binder. Further exploration of methods to improve HCMA’s storage stability, real-scale corroboration on trial section and life cycle assessment of asphalt pavement containing hydrochar modifiers will be followed in the future.

Download Full-text

Rheological and Microbiological Characteristics of Hops and Hot Trub Particles Formed during Beer Production

Molecules ◽

10.3390/molecules26030681 ◽

2021 ◽

Vol 26 (3) ◽

pp. 681

Author(s):

Monika Sterczyńska ◽

Marek Zdaniewicz ◽

Katarzyna Wolny-Koładka

Keyword(s):

Rheological Properties ◽

Raw Materials ◽

Raw Material ◽

Microbiological Analysis ◽

Waste Products ◽

Low Viscosity ◽

Post Process ◽

High Shear Rates ◽

Different Temperatures ◽

Beer Production

During the production of beer, and especially beer wort, the main wastes are spent grain and hot trub, i.e., the so-called “hot break.” Combined with yeast after fermentation, they represent the most valuable wastes. Hot trub is also one of the most valuable by-products. Studies on the chemical composition of these sediments and their rheological properties as waste products will contribute to their effective disposal and even further use as valuable pharmaceutical and cosmetic raw materials. So far, hot trub has been studied for morphology and particle distribution depending on the raw material composition and beer wort extract. However, there are no preliminary studies on the rheological properties of hot trub and hops. In particular, no attention has yet been paid to the dependence of these properties on the hop variety or different protein sources used. The aim of this study was to examine the effect of different hopping methods on hot trub viscosity and beer wort physicochemical parameters. Additionally, the hop solutions were measured at different temperatures. A microbiological analysis of hop sediments was also performed to determine the post-process survival of selected microorganisms in these wastes. For manufacturers of pumps used in the brewing industry, the most convenient material is that of the lowest viscosity. Low viscosity hot trub can be removed at lower velocities, which reduces costs and simplifies washing and transport. The sediments also had similar equilibrium viscosity values at high shear rates.

Download Full-text

Anaerobic treatment of municipal wastewater using the UASB-technology

Water Science & Technology ◽

10.2166/wst.2007.732 ◽

2007 ◽

Vol 56 (10) ◽

pp. 37-44 ◽

Cited By ~ 15

Author(s):

I. Urban ◽

D. Weichgrebe ◽

K.-H. Rosenwinkel

Keyword(s):

Co2 Emission ◽

Municipal Wastewater ◽

Clean Energy ◽

Anaerobic Treatment ◽

Relevant Effect ◽

Different Temperatures ◽

High Concentrations ◽

New Applications ◽

Uasb Reactors ◽

Positive Effect

The anaerobic treatment of municipal wastewater enables new applications for the reuse of wastewater. The effluent could be used for irrigation as the included nutrients are not affected by the treatment. Much more interesting now are renewable energies and the retrenchment of CO2 emission. With the anaerobic treatment of municipal wastewater, not only can the CO2 emission be reduced but “clean” energy supply can be gained by biogas. Most important for the sustainability of this process is the gathering of methane from the liquid effluent of the reactor, because the negative climate-relevant effect from the degassing methane is much higher than the positive effect from saving CO2 emission. In this study, UASB reactors were used with a flocculent sludge blanket for the biodegradation of the carbon fraction in the wastewater with different temperatures and concentrations. It could be shown that the positive effect is much higher for municipal wastewater with high concentrations in hot climates.

Download Full-text

Comparison of Moving-Bed Catalytic Tar Hydrocracking Processes

Processes ◽

10.3390/pr9030500 ◽

2021 ◽

Vol 9 (3) ◽

pp. 500

Author(s):

Vladimir Kapustin ◽

Elena Chernysheva ◽

Roman Khakimov

Keyword(s):

Heterogeneous Catalysts ◽

Process Management ◽

Raw Materials ◽

Oil Industry ◽

Oil Refining ◽

Hydrocarbon Potential ◽

Vacuum Residue ◽

Advantages And Disadvantages ◽

Major Process ◽

Liquid Products

In recent years, there has been a trend in the global oil industry to improve the proportion of heavy high-sulfur crude oils in the total volume of extracted and processed resources, reserves of which are estimated at over 800 billion metric tons. Therefore, the main line of oil refining is processing of heavy crudes and residua to allow maximum use of the hydrocarbon potential and yield of high-margin products. Hydrogenation processes of heavy raw materials are most attractive in terms of product quality. This article analyzes tar hydrocracking processes that are either in operation or at the stage of full-scale testing. These include Veba Combi-Cracker (VCC), Uniflex, suspended-bed catalyst hydrocracking (ENI), and vacuum residue hydroconversion (TIPS RAS). These technologies use heterogeneous catalysts and are designed to obtain the largest possible amount of liquid products. This article discusses the features of each technology, highlights their advantages and disadvantages, shows the main approaches to process management, and speculates about the development of these technologies. Tar refining is a major process in heavy oil upgrading, and the development of efficient tar-processing methods will influence refinery configurations and management.

Download Full-text

Preparation of Low Chlorine Shellac from Seedlac by Dechlorination Process Using Pd/Fe Binary Metal as Catalyst

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.1879 ◽

2009 ◽

Vol 79-82 ◽

pp. 1879-1882 ◽

Cited By ~ 2

Author(s):

Ya Long Liao ◽

Fu Chang Xu ◽

Dong Bo Li

Keyword(s):

Reaction Temperature ◽

Catalytic Hydrogenation ◽

Large Scale ◽

Raw Materials ◽

Chemical Deposition ◽

Structure Characterization ◽

Binary Metal ◽

Elementary Analysis ◽

Chlorine Ions ◽

Ultraviolet Spectrophotometer

Pd/Fe bimetallic catalysts were synthesized via chemical deposition and used to eliminate chlorine compacted in shellac while it was being bleached with sodium hypochlorite in alkaline solution for the preparation of low chlorine shellac, a natural and biological product used in large scale in food industry and pharmaceutical fields. Experiments demonstrated that the Pd/Fe bimetallic particles could catalyze dechlorination process effectively, which was affected by several factors such as reaction temperature, Pd/Fe ratio, and the induction of Pd/Fe. The dechlorination efficiency reached 81.9% under the conditions of Pd/Fe loading ratio of 0.10wt%, binary metal usage 10 g/L, H2 flowing rate 50 mL/min, and reaction temperature 90°C for 240 min. Moreover, the mechanism of catalytic hydrogenation was elucidated through structure characterization of the final products using elementary analysis, infrared spectroscopy, and ultraviolet spectrophotometer. It was shown from the result of ultraviolet spectrophotometer that the wavelength of the maximum absorption of seedlac, the raw materials for obtaining shellac, was 235 nm. However, it was blue shifted to the same value 222 nm when the shellac was dechlorinated by catalytic hydrogenation with Pd/Fe binary metal particle as the shellac without catalyzed. The results of elementary analysis showed that chlorine content in the final product was only 0.46%, just 1/5 comparing to that of non-declorination by catalytic hydrogenation under the optimum conditions. It was shown that the chlorine ions compacted in the shellac was substituted by hydrogen ions.

Download Full-text

Hydrotreating of Hydrochloric Acid Lignin in a Hydrogen-Donor Solvent

Journal of Wood Chemistry and Technology ◽

10.1080/02773818208085117 ◽

1982 ◽

Vol 2 (1) ◽

pp. 17-31 ◽

Cited By ~ 13

Author(s):

Tor P. Schultz ◽

Raymond J. Preto ◽

J. Lynn Pittman ◽

Irving S. Goldstein

Keyword(s):

Hydrochloric Acid ◽

Hydrogen Donor ◽

Donor Solvent

Download Full-text

Synthesis of Polyurethane Dendrimers and Transfer Properties of Dye

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.457-458.65 ◽

2013 ◽

Vol 457-458 ◽

pp. 65-71

Author(s):

Jing Ru Jia

Keyword(s):

Methyl Orange ◽

Phase Transfer ◽

Raw Materials ◽

Toluene Diisocyanate ◽

Polymerization Process ◽

Process Conditions ◽

Addition Polymerization ◽

Different Temperatures ◽

The Difference ◽

Transfer Properties

The polyfunctional organic compounds 2- hydroxymethyl -1,4- butanediol (trihydric alcohol) and toluene diisocyanate -2, 4- diisocyanate (TDI) were taken as the raw materials in this study. A polyurethane dendrimer was synthesized by utilizing the difference in the reaction activity of two isocyanate groups of TDI at different temperatures. The polymerization process conditions were studied. The addition polymerization of para-position NCO groups occurred at 50 °C, and that of ortho NCO groups occurred at 90 °C. According to the structure of the dendrimer synthesized, methyl orange was used as the guest molecule. Consequently, the aqueous methyl orange showed a phase transfer. With the increase of dendrimer concentration, the transfer rate of methyl orange increased.

Download Full-text

The role of acidity profile in the nanotubular growth of polyaniline

Chemical Papers ◽

10.2478/s11696-009-0101-z ◽

2010 ◽

Vol 64 (1) ◽

Cited By ~ 26

Author(s):

Elena Konyushenko ◽

Miroslava Trchová ◽

Jaroslav Stejskal ◽

Irina Sapurina

Keyword(s):

Acetic Acid ◽

Sulfuric Acid ◽

Reaction Temperature ◽

Subsequent Growth ◽

Subsequent Oxidation ◽

Ammonium Peroxydisulfate ◽

Aniline Oligomers ◽

Positive Effect ◽

Granular Morphology

AbstractConditions of polyaniline (PANI) nanotubes preparation were analyzed. Aniline was oxidized with ammonium peroxydisulfate in 0.4 M acetic acid. There are two subsequent oxidation steps and the products were collected after each of them. At pH > 3, neutral aniline molecules are oxidized to non-conducting aniline oligomers. These produce templates for the subsequent growth of PANI nanotubes, which takes place preferably at pH 2–3. At pH < 2, granular morphology of the conducting PANI is obtained. High final acidity of the medium should be avoided in the preparation of nanotubes, e.g., by reducing the amount of sulfuric acid which is a by-product. Reduction of the peroxydisulfate-to-aniline mole ratio was tested for this purpose in the present study. Lowering of the reaction temperature from 20°C to −4°C had a positive effect on the formation of nanotubes.

Download Full-text