scholarly journals ВЛИЯНИЕ ТЕХНОЛОГИЧЕСКОГО РЕЖИМА УСТАНОВКИ ТЕРМИЧЕСКОГО ПИРОЛИЗА УГЛЕВОДОРОДОВ НА КАЧЕСТВЕННЫЙ СОСТАВ ТЯЖЁЛОЙ СМОЛЫ

World Science ◽  
2019 ◽  
Vol 1 (1(41)) ◽  
pp. 29-35
Author(s):  
Садыгов Ф. М. ◽  
Магеррамова З. Ю. ◽  
Гаджиев Г. Н. ◽  
Гасан-заде Г. Г. ◽  
Мамедова И. Г. ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Maximum Yield ◽  
Optimum Process ◽  
Quantitative Composition ◽  
Process Conditions ◽  
Low Molecular Weight ◽  
Technological Parameters ◽  
Alkyl Derivatives ◽  
Liquid Products ◽  
Heavy Pyrolysis Resin

The dependence of the yield and composition of the heavy pyrolysis resin on the initial hydrocarbon feedstock and the process conditions is investigated. The variation of technological parameters within certain limits leads to a change in the content of low molecular weight olefins in the gaseous pyrolysis products, as well as the qualitative and quantitative composition of by-product liquid products. As a result of the research, the optimum process conditions for the pyrolysis of straight-run gasoline were determined, which, with the maximum conversion of hydrocarbons to low-molecular-weight olefins, significantly increases the yield of heavy resin containing a wide fraction of naphthalene, biphenyl, indene and their alkyl derivatives. It is shown that when treating by-products containing valuable hydrocarbons as target products and combining the technological mode of pyrolysis and their composition, it is possible to achieve along with the maximum yield of low molecular weight olefins, a significant yield of heavy pyrolysis resin and qualitative changes in its composition.

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.

Preparation of low-molecular-weight chitosan by enzymatic hydro-lysis for use in peliculture

2021 ◽  
pp. 31-33
Author(s):  
Элана Игоревна Ковалева ◽  
Марина Алексеевна Фролова ◽  
Алексей Иванович Албулов ◽  
Валерий Петрович Варламов ◽  
Анатолий Константинович Елисеев
Keyword(s):  
Molecular Weight ◽  
Enzymatic Hydrolysis ◽  
Environmental Factors ◽  
Low Molecular Weight ◽  
Technological Parameters ◽  
Low Molecular Weight Chitosan

Хитозан и его производные обладают множеством свойств, которые позволяют применять его в пчеловодстве. Он повышает устойчивость организма пчел к неблагоприятным факторам внешней среды и к возбудителям различных заболеваний. В результате проведенных исследований разработаны технологические параметры получения низкомолекулярного хитозана методом ферментативного гидролиза. Chitosan and its derivatives have many properties that allow them to be used in beekeeping. It increases the resistance of the bee organism to adverse environmental factors and to pathogens of various diseases. As a result of the conducted research, the technological parameters for the production of low-molecular-weight chitosan by enzymatic hydrolysis were developed.

Qualification of HSQC methods for quantitative composition of heparin and low molecular weight heparins

2017 ◽  
Vol 136 ◽  
pp. 92-105 ◽  
Author(s):  
Lucio Mauri ◽  
Giovanni Boccardi ◽  
Giangiacomo Torri ◽  
Michael Karfunkle ◽  
Eleonora Macchi ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Quantitative Composition ◽  
Low Molecular Weight ◽  
Low Molecular Weight Heparins

scholarly journals Justification of bioactivated grain triticale use in alcohol production

2019 ◽  
Vol 48 (1) ◽  
pp. 57-65
Author(s):  
Анна Миронцева ◽  
Anna Mirontseva ◽  
Елена Цед ◽  
Elena Tsed ◽  
Светлана Волкова ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Chemical Composition ◽  
Ethyl Alcohol ◽  
Yeast Cells ◽  
Low Molecular Weight ◽  
Technological Parameters ◽  
Alcohol Production ◽  
Enzyme Preparations ◽  
Green Mass ◽  
Low Molecular Weight Compounds

Triticale accounts for the biggest share in gross processing and state procurement of grain in Belarussian production of alcohol. The main difficulty in its processing is the formation of viscous technological fluids due to the presence of non-starch polysaccharides in its chemical composition. All measures taken to solve the problem come down to the selection of the efficient enzyme preparations, hydrolyzing grain polymers into low molecular weight compounds, which have the ability to be disposed by the yeast cells and form the ethyl alcohol. But grain own enzymes are not involved. It is possible to solve the problem by means of biological activation, which will activate grain enzyme systems and partially hydrolyze grain polymers into low molecular weight compounds. The article considers general and special technological parameters of six cultivars of triticale selected in the Republic of Belarus: Antos, Kastus, Dubrava, Run, Prometheus, Impulse. The authors determined that the most promising cultivars for bioactivation and food grade ethyl alcohol production are Antos and Dubrava. The authors explored the possibility of using hot soaking of triticale grain for the biological activation. They also showed the advantages of introduction of amaranth green mass in the amount of 8% during hot soaking for the reduction of grain microbiological contamination. They studied the changes in the technological properties of triticale cultivars Antos and Dubrava after the bioactivation with the green mass of amaranth. The authors determined that grain microbiological characteristics improved, the activity of grain enzymes increased, proportion of low molecular weight compounds in the chemical composition increased. They studied the processes taking place during wort and mash production from the bioactivated triticale grain. The authors showed that the processing of bioactivated triticale grain resulted in the production of wort with higher concentration of dry matter which allowed to increase the ethanol content in the mature mash produced from triticale cultivar Antos by 19.5% and from the triticale cultivar Dubrava by 29.3% and reduce the total quantity of the main impurities in distillates.

EVALUATION OF TECHNOLOGICAL PARAMETERS OF ASPHALT CONCRETE MIXTURES FOR THE STREET-ROAD NETWORK IN URBAN AGGROMERATIONS USING ADDITIVES OF POLYETHYLENE WITH LOW MOLECULAR WEIGHT

2021 ◽  
pp. 85-96
Author(s):  
Александр Борисович Соломенцев ◽  
Моиз Режист ◽  
Швендески Маселюс Жозеф
Keyword(s):  
Molecular Weight ◽  
Structure Formation ◽  
Dynamic Viscosity ◽  
Asphalt Concrete ◽  
Road Network ◽  
Low Molecular Weight ◽  
Polymer Additives ◽  
Polymer Additive ◽  
Technological Parameters ◽  
Concrete Mixtures

Получены значения динамической вязкости битумного вяжущего с добавками низкомолекулярного полиэтилена в температурном интервале 60…160 °С. При введении полимерных добавок в дорожный битум вязкость битума повышается. Наиболее высокие значения динамической вязкости наблюдаются у полимерной добавки Вискодор - ПВ1, это ярко выражено при расходе 4 % добавки от массы битума и при температурах ниже 130°С. Добавка неокисленного низкомолекулярного полиэтилена Honeyvell Titan 7205 увеличивает вязкость в большей степени, чем добавка окисленного полиэтилена Honeyvell Titan 7686. Определены допустимые технологические температуры асфальтобетонных смесей с полимерными добавками на этапах структурообразования асфальтобетона. We obtained the values of the dynamic viscosity of bitumen binder with additives of polyethylene with low molecular weight in the temperature range of 60…160 °C. When polymer additives are introduced into road bitumen, the viscosity of bitumen increases. The highest values of dynamic viscosity are observed for the polymer additive Viskodor - PV1, this is clearly pronounced at the consumption of 4 % of the additive based on the mass of bitumen and at temperatures below 130 °С. The additive of unoxidized low molecular weight polyethylene Honeyvell Titan 7205 increases the viscosity to a greater extent than the additive of oxidized polyethylene Honeyvell Titan 7686. We determined as well the permissible technological temperatures of asphalt concrete mixtures with polymer additives at the stages of structure formation of asphalt concrete.

Characterization of Low-Molecular-Weight Heparins by Strong Anion-Exchange Chromatography

2017 ◽  
Vol 100 (6) ◽  
pp. 1706-1714 ◽  
Author(s):  
Radosław Sadowski ◽  
Renata Gadzała-Kopciuch ◽  
Tomasz Kowalkowski ◽  
Paweł Widomski ◽  
Ludwik Jujeczka ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Anion Exchange ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Quantitative Composition ◽  
Low Molecular Weight ◽  
Strong Anion Exchange ◽  
Post Hoc ◽  
First Time

Abstract Currently, detailed structural characterization of low-molecular-weight heparin (LMWH) products is an analytical subject of great interest. In this work, we carried out a comprehensive structural analysis of LMWHs and applied a modified pharmacopeial method, as well as methods developed by other researchers, to the analysis of novel biosimilar LMWH products; and, for the first time, compared the qualitative and quantitative composition of commercially available drugs (enoxaparin, nadroparin, and dalteparin). For this purpose, we used strong anion-exchange (SAX) chromatography with spectrophotometric detection because this method is more helpful, easier, and faster than other separation techniques for the detailed disaccharide analysis of new LMWH drugs. In addition, we subjected the obtained results to statistical analysis (factor analysis, t-test, and Newman–Keuls post hoc test).

scholarly journals Optimization of liquid-phase α-pinene oxidation with oxygen in presence of cobalt (II) stearate

2019 ◽  
Vol 55 (2) ◽  
pp. 233-239
Author(s):  
A. A. Sosnovskaya ◽  
V. L. Fleisher ◽  
Y. V. Borkina
Keyword(s):  
Liquid Phase ◽  
Flow Rate ◽  
Air Flow ◽  
Maximum Yield ◽  
Oxidation Products ◽  
High Conversion ◽  
Optimum Process ◽  
Process Conditions ◽  
Air Flow Rate ◽  
Quantitative Content

Optimization of the liquid-phase oxidation of α-pinene was carried out using the Box plan. It was found that an increase in the temperature of the oxidation process in the interval 55–85 °C leads to an increase in the amount of polymers from 45 to 55 %, and a decrease in the air flow rate from 1000 to 600 ml/min – to a 10 % decrease in terpenic oxygencontaining compounds (verbenol, verbenon, epoxy α-pinene). Increasing the duration of oxidation from 5 to 15 h leads to a reduction in the content of α-pinene from 70 to 48 %, which indicates its high conversion. The results of the experimental plan have been processed, the optimum process conditions found, which ensure the maximum yield terpenic oxygencontaining compounds and a high conversion α-pinene with the minimum content of polymers in the oxidation products, have been calculated and confirmed in practice. It was established that at a temperature of 70–75 °C, an air flow rate of 1000 ml/min and an oxidation time of 5 h, the quantitative content of the main products was: terpenic oxygen-containing compounds – 27.04 %, monomers – 69.70 %, polymers – 30.30 %.

scholarly journals POLYPHENOLS OF ARCTIC BROWN ALGAE: EXTRACTION, POLYMOLECULAR COMPOSITION

2019 ◽  
pp. 65-75
Author(s):  
Konstantin Grigor'yevich Bogolitsin ◽  
Anna Sergeyevna Druzhinina ◽  
Denis Vladimirovich Ovchinnikov ◽  
Anastasiya Eduardovna Parshina ◽  
Elena Valeriyevna Shulgina ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Molecular Weight ◽  
Brown Algae ◽  
Maximum Yield ◽  
Gel Filtration ◽  
Fucus Vesiculosus ◽  
Polyphenolic Compounds ◽  
Biologically Active ◽  
Low Molecular Weight ◽  
High Biological Activity

Arctic brown algae of the species Fucus vesiculosus are characterized by a high content of polyphenolic compounds - phlorotannins, exhibiting high biological activity. The aim of this study is to develop a methodology for the isolation and analysis of biologically active polyphenolic compounds from arctic brown algae. The proposed scheme for the isolation of polyphenols from Fucus vesiculosus brown algae is based on the principles of "green chemistry" and is carried out by sequential disassembly of the biomass of the plant object with the release of associated components (lipid-pigment complex, polysaccharides, mannitol) and maximum yield of polyphenol fraction. As a result of the experimental work, the optimal parameters for carrying out each stage of the proposed scheme were determined and a stepwise assessment of its effectiveness was carried out. The extractable fraction of polyphenols contains up to 67% of polyphenols relative to their content in the initial biomass, and the proportion of polyphenols in the fraction is up to 83%. A study of the phlorotannins fraction showed that its antioxidant activity is meaningful and it was 553±24 (mg of ascorbic acid/g extract). The polymolecular composition of the target fraction was investigated by the method of exclusion gel filtration chromatography, which showed the polymodal distribution, indicating the presence of several groups of components - low molecular weight and high molecular weight phlorotannins with masses ranging from thousands to hundreds of thousands of Daltons. The data obtained using chromatography-mass spectrometry and MALDI mass spectrometry make it possible to identify the presence of low molecular weight phlorotannins in the polyphenol fraction with masses from 250 to 1638 Da, which are close analogues in structure.

scholarly journals TiO2 Nanoparticles As Heterogeneous Catalyst For WCO Biodiesel Production: Engine Parameters Optimization and Prediction of Biodiesel/Diesel/Cadmium (II) Coordination Polymer Blends Fuel By Using Response Surface Methodology

2022 ◽  
Author(s):  
Medhat Elkelawy ◽  
Safaa El-din H. Etaiw ◽  
Ahmed Mohamed Radwan ◽  
Hitesh Panchal ◽  
Hagar Alm-Eldin Bastawissi
Keyword(s):  
Coordination Polymer ◽  
Heterogeneous Catalyst ◽  
Heterogeneous Catalysts ◽  
Direct Injection ◽  
Maximum Yield ◽  
Parameters Optimization ◽  
Biodiesel Production ◽  
Nano Particles ◽  
Optimum Process ◽  
Process Conditions

Abstract Nowadays, combustion technologies decarbonization, reduction of harmful emission, and improving thermal efficiency have gained more attention by using clean, sustainable, alternative, and reliable biofuels coupled with using nano particles technologies. Nano heterogeneous catalysts are new promising technologies for converting triglycerides (oil, fats,..etc) into biodiesel, which characterized with saving in the total cost of production. Titanium dioxide (TiO2) nano heterogeneous catalyst used to convert triglyceride represented in waste cooking oil (WCO) into FAME as bio-diesel, where bio-diesel yield fitted the ASTM. In the present research, the results show 95% as a maximum yield at optimum process conditions of 0.01 Wt.% TiO2 loading, 0.3 Wt.% NaoH, reaction temperature (60 ºC), reaction time (60 min), 10:1 methanol to oil volumetric percentage. Effect of mixing different percentage (35, and 70 ppm) of {[Cd (EIN)2(SCN)2]}, SCP 1, Cadmium (II coordination polymer as nanoparticle enhancer, with diesel fuel/biodiesel (60:40 v/v%) (D60B40) on the behavior of one-cylinder direct-injection diesel (DI) engine parameters were examined experimentally and analytically through RSM methodologies. The engine operating variables have been optimized by using CCD method to achieve an optimal BTE. Engine load and nano particles quantity were considered as process input variables to optimize BTE, UHC, and NOx emissions as engine responses. The quadratic regression models were significant and adequate statistically as indicated by the Analysis of variance (ANOVA). The obtained results from (RSM) optimizer indicated that BTE, NOx, and UHC have optimum values of 16.2605%, 544.9157 ppm, and 117.6023 ppm respectively, at 70 ppm of SCP 1 nanoparticles and 2.1919 Kw of break power as optimal predicted values. A validation examination was carried out and the percent of error was within the limit of 5%. BTE, UHC, and NOx have an error percentage of 2.05%, 1.03%, and 1.63%, respectively.

scholarly journals Effects of Process Parameters on Hydrolytic Treatment of Black Liquor for the Production of Low-Molecular-Weight Depolymerized Kraft Lignin

Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2464 ◽  
Author(s):  
Zaid Ahmad ◽  
Nubla Mahmood ◽  
Zhongshun Yuan ◽  
Michael Paleologou ◽  
Chunbao Xu
Keyword(s):  
Molecular Weight ◽  
Reaction Time ◽  
Black Liquor ◽  
Average Molecular Weight ◽  
Research Work ◽  
Kraft Lignin ◽  
Hydroxyl Group ◽  
Process Conditions ◽  
Low Molecular Weight ◽  
Capping Agent

The present research work aimed at hydrolytic treatment of kraft black liquor (KBL) at 200–300 °C for the production of low-molecular-weight depolymerized kraft lignin (DKL). Various process conditions such as reaction temperature, reaction time, initial kraft lignin (KL) substrate concentration, presence of a catalyst (NaOH), capping agent (phenol) or co-solvent (methanol) were evaluated. The research demonstrated effective depolymerization of KL in KBL at 250–300 °C with NaOH as a catalyst at a NaOH/lignin ratio of about 0.3 (w/w) using diluted KBL (with 9 wt. % KL). Treatment of the diluted KBL at 250 °C for 2 h with 5% addition of methanol co-solvent produced DKL with a weight-average molecular weight (Mw) of 2340 Da, at approx. 45 wt. % yield, and a solid residue at a yield of ≤1 wt. %. A longer reaction time favored the process by reducing the Mw of the DKL products. Adding a capping agent (phenol) helped reduce repolymerization/condensation reactions thereby reducing the Mw of the DKL products, enhancing DKL yield and increasing the hydroxyl group content of the lignin. For the treatment of diluted KBL (with 9 wt. % KL) at 250 °C for 2 h, with 5% addition of methanol co-solvent in the presence of NaOH/lignin ≈ 0.3 (w/w), followed by acidification to recover the DKL, the overall mass balances for C, Na and S were measured to be approx. 74%, 90% and 77%, respectively. These results represent an important step towards developing a cost-effective approach for valorization of KBL for chemicals.

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