scholarly journals Mathematical modeling of the process of obtaining raw material for manufacturing sorbents of medical purpose

2020 ◽  
Vol 61 (3) ◽  
pp. 49-58
Author(s):  
Ilnar A. Valeev ◽  
◽  
Irina V. Zhukova ◽  
Azat A. Girfanutdinov ◽  
◽  
...  
Keyword(s):  
Activated Carbon ◽  
Theoretical Calculations ◽  
Pressure Gauge ◽  
Experimental Studies ◽  
Raw Material ◽  
Absolute Pressure ◽  
Operating Pressure ◽  
Pyrolysis Process ◽  
Simple Method ◽  
Real Process

This article analyzes the production and use of affordable medical sorbents in the Russian and international markets. The analysis showed that there is a shortage of production of cheap specific activated carbon in Russia, due to insufficient expansion of the range. Today, the price of coal tends to increase, so many manufacturers are puzzled by the creation of an effective system for processing coal. It was suggested to use burnt charcoal from various types of wood, since it is one of the optimal types of sorbents, taking into account the economic aspect and the naturalness of the raw materials used for the production of activated carbon. An efficient and simple method of processing burnt coal-pyrolysis-was also proposed. Verification of the model's adequacy to the real process was performed by comparing the results of experimental studies with the results of theoretical calculations. The basic kinetic and thermophysical equations that are used today to study the kinetics of pyrolysis of activated carbon are studied. To find out whether a change in pressure can affect the course of the pyrolysis process, an experimental setup was developed and a series of experiments were conducted. Wood samples were used for experiments. 25x25x25 mm and humidity 10%. The volume of one-time loading was 50 g. The operating pressure in the pyrolysis chamber was recorded by a pressure gauge and set using ejector pumps (pressure reducers), whose performance was regulated and was 0.9, 0.8, 0.7, 0.6, 0.5 kPa, or a nitrogen cylinder (pressure increase) to the absolute pressure values 1, 2, 3, 4, 5, 6 kPa.A comparative analysis of mathematical calculations and a number of experimental data conducted on warty birch was also carried out. A mathematical model of the wood pyrolysis process is proposed, which takes into account pre-drying, kinetics, the amount of volatile products released, and cooling of the finished charcoal.

Carbon nanotubes produced from rubber fruit shell activated carbon

2021 ◽  
pp. 2140003
Author(s):  
Suhdi ◽  
Sheng-Chang Wang
Keyword(s):  
Carbon Nanotubes ◽  
Activated Carbon ◽  
Low Temperature ◽  
Chemical Activation ◽  
Hydrothermal Process ◽  
Average Diameter ◽  
Raw Material ◽  
Crystallographic Structure ◽  
Simple Method ◽  
Two Peaks

This study used rubber fruit shells (RFS) as raw material for making carbon nanotubes (CNTs). The CNTs were carried out by hydrothermal process at low-temperature after carbonization and chemical activation was done. This experiment succeeded in obtaining a bundle of MWCNT (Multi-Wall Nanotube) from the raw material of RFS. The results of characterization using SEM and TEM showed that the resulting CNTs were not homogeneous in diameter, ranging from 13 to 455 nm, with an average diameter of about 179 nm. XRD was used to identify crystallographic structure; it has two peaks 2[Formula: see text] at around 26.0 and 44.0, index to 002 and 101 reflections hexagonal graphite diffraction of the MWCNTs. This study can provide an alternative inexpensive raw material and a simple method to obtain carbon nanotubes.

Reuse of manganese sulfate as raw material by recovery from pesticide's wastewater using nanofiltration and electro-electrodialysis: process simulation and analysis from actual data

2020 ◽  
Author(s):  
Ricardo Mejía Marchena ◽  
Aymer Maturana Córdoba ◽  
Diego Gomez Cerón ◽  
Christian Quintero Monroy ◽  
Luis Arismendy Montes ◽  
...  
Keyword(s):  
Experimental Studies ◽  
Chemical Precipitation ◽  
Economic Resources ◽  
Raw Material ◽  
Industrial Plant ◽  
Manganese Sulfate ◽  
Selective Recovery ◽  
Membrane Performance ◽  
Real Process

Abstract Reuse of wastewater, as well as recovery of valuable, toxic or harmful products in industrial discharges, still represents an important issue, not only because it reduces the effect on receiving water bodies, but also because of the economic resources it represents for industry itself. In this research, in situ regeneration of Mn2SO4 is evaluated, for its reuse as the main raw material in the original process of a fungicide plant. The regeneration is evaluated by selective recovery of Mn2+, Zn2+ and SO4= present in the wastewater produced by the industrial plant, and utilizing nanofiltration, electro-electrodialysis and chemical precipitation as separation alternatives. Each alternative was designed and evaluated technically and economically through simulations in Aspen Plus®, with data and information of the real process supplied by the company. Because zinc concentration is relatively low, its selective recovery was not attractive. The resulting Mn2SO4 solution and treated water quality in conventional alternatives were significantly poor with high costs. In contrast, nanofiltration and electro-electrodialysis alternatives generate water and by-products of higher quality and reuse potential with significantly lower costs. However, their viability depends on the membrane performance. The results were satisfactory, but future experimental studies are required to optimize the alternatives and define the correct pretreatment process.

Theoretical and experimental studies of palladium-catalyzed site-selective C(sp3)−H bond functionalization enabled by transient ligands

2017 ◽  
Author(s):  
Haibo Ge ◽  
Lei Pan ◽  
Piaoping Tang ◽  
Ke Yang ◽  
Mian Wang ◽  
...  
Keyword(s):  
Bond Activation ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Bond Functionalization ◽  
Aliphatic Ketones ◽  
Site Selectivity ◽  
Mechanistic Investigation ◽  
Palladium Catalyzed ◽  
Metal Catalyzed ◽  
Site Selective

Transition metal-catalyzed selective C–H bond functionalization enabled by transient ligands has become an extremely attractive topic due to its economical and greener characteristics. However, catalytic pathways of this reaction process on unactivated sp<sup>3</sup> carbons of reactants have not been well studied yet. Herein, detailed mechanistic investigation on Pd-catalyzed C(sp<sup>3</sup>)–H bond activation with amino acids as transient ligands has been systematically conducted. The theoretical calculations showed that higher angle distortion of C(sp2)-H bond over C(sp3)-H bond and stronger nucleophilicity of benzylic anion over its aromatic counterpart, leading to higher reactivity of corresponding C(sp<sup>3</sup>)–H bonds; the angle strain of the directing rings of key intermediates determines the site-selectivity of aliphatic ketone substrates; replacement of glycine with β-alanine as the transient ligand can decrease the angle tension of the directing rings. Synthetic experiments have confirmed that β-alanine is indeed a more efficient transient ligand for arylation of β-secondary carbons of linear aliphatic ketones than its glycine counterpart.<br><br>

Applications of Bentonite to Soil Decontamination

2018 ◽  
Vol 69 (7) ◽  
pp. 1695-1698
Author(s):  
Marin Rusanescu ◽  
Carmen Otilia Rusanescu ◽  
Gheorghe Voicu ◽  
Mihaela Begea
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Laboratory Experiments ◽  
Experimental Studies ◽  
Heavy Metal Concentration ◽  
Polluted Soil ◽  
Raw Material ◽  
Soil Decontamination ◽  
Metal Retention ◽  
Removal Of Heavy Metals

A calcium bentonite from Orasu Nou deposit (Satu Mare Romania) was used as raw material. We have conducted laboratory experiments to determine the influence of bentonite on the degree of heavy metal retention. It has been observed that the rate of retention increases as the heavy metal concentration decreases. Experimental studies have been carried out on metal retention ( Zn) in bentonite. In this paper, we realized laboratory experiments for determining the influence of metal (Zn) on the growth and development of two types of plants (Pelargonium domesticum and Kalanchoe) and the effect of bentonite on the absorption of pollutants. These flowers were planted in unpolluted soil, in heavy metal polluted soil and in heavy metal polluted soil to which bentonite was added to observe the positive effect of bentonite. It has been noticed that the flowers planted in unpolluted soil and polluted with heavy metals to which bentonite has been added, the flowers have flourished, the leaves are still green and the plants whose soils have been polluted with heavy metals began to dry after 6 days, three weeks have yellowish leaves and flowers have dried. Experiments have demonstrated the essential role of bentonite for the removal of heavy metals polluted soil.

scholarly journals Experimental Study on the Water Selective Dense Membrane under an Absolute Pressure Difference with Simplified Test Method

2021 ◽  
Vol 11 (4) ◽  
pp. 1710
Author(s):  
Jinwook Lee ◽  
Hyo-Sun Kim ◽  
Donik Ku ◽  
Jihun Lim ◽  
Minkyu Jung ◽  
...  
Keyword(s):  
Measurement Methods ◽  
Test Method ◽  
Coefficient Of Performance ◽  
Absolute Pressure ◽  
Air Conditioner ◽  
Experimental Conditions ◽  
Simple Method ◽  
Performance Factors ◽  
Dense Membrane ◽  
Before And After

Membrane-based vacuum dehumidification technology is currently being actively studied. In most studies, the performance of the membrane-based systems is evaluated under the assumption that the membrane can achieve ideal separation, which results in ideal coefficient of performance (COP) values. However, the performance factors for membranes vary depending on the experimental conditions and measurement methods. Therefore, relevant values can only be calculated if the data are measured in an environment close to that of the application conditions. The cup measurement method is a simple method to measure the permeability, however, there are limitations regarding adding variables during the experiment. To overcome these limitations, a new experimental device was constructed that combines pressurized cell with the cup method. Using the device, the performance of polyethylene-amide-bonded dense membranes was evaluated under conditions where absolute pressure differentials occurred before and after the membrane, such as in air conditioner dehumidification systems.

scholarly journals Study on Adsorption Properties of Modified Corn Cob Activated Carbon for Mercury Ion

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4483
Author(s):  
Yuyingnan Liu ◽  
Xinrui Xu ◽  
Bin Qu ◽  
Xiaofeng Liu ◽  
Weiming Yi ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Photoelectron Spectroscopy ◽  
Adsorption Process ◽  
Physical Adsorption ◽  
Raw Material ◽  
Order Kinetic ◽  
Mercury Ions ◽  
Corn Cob ◽  
Adsorption Time ◽  
X Ray

In this study, corn cob was used as raw material and modified methods employing KOH and KMnO4 were used to prepare activated carbon with high adsorption capacity for mercury ions. Experiments on the effects of different influencing factors on the adsorption of mercury ions were undertaken. The results showed that when modified with KOH, the optimal adsorption time was 120 min, the optimum pH was 4; when modified with KMnO4, the optimal adsorption time was 60 min, the optimal pH was 3, and the optimal amount of adsorbent and the initial concentration were both 0.40 g/L and 100 mg/L under both modified conditions. The adsorption process conforms to the pseudo-second-order kinetic model and Langmuir model. Scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and Zeta potential characterization results showed that the adsorption process is mainly physical adsorption, surface complexation and ion exchange.

Studying the Effect of some Factors on the Stress-Strain Behavior of the Rostov Region Limestones in the Course of their Production and Use

2021 ◽  
Vol 1022 ◽  
pp. 80-86
Author(s):  
Mikhail G. Kholodnyak ◽  
Sergey A. Stelmakh ◽  
Evgeniy M. Shcherban ◽  
Mukhuma P. Nazhuev
Keyword(s):  
Construction Material ◽  
Experimental Studies ◽  
Raw Material ◽  
Material Base ◽  
Strain Behavior ◽  
Current State ◽  
Rostov Region ◽  
Literary Sources ◽  
Crushed Granite ◽  
Strain Stress

The paper considers the current state of the mineral raw material base and the construction material market of the Rostov Region. The effect of various factors on the strain-stress behavior of local limestones has been investigated. The scientific and technical literary sources devoted to the processes of rock failure under various loads have been analyzed. The experimental studies have shown that the tested samples of limestone with a high content of cuboidal grains have characteristics comparable to those of the crushed granite stone. It has been concluded that the use of the Rostov Region limestones in the construction industry is competitive and feasible, provided the proper implementation of the engineering measures proposed in their production.

Chemistry of the Gasification of Carbonaceous Raw Material

2021 ◽  
Vol 1045 ◽  
pp. 67-78
Author(s):  
Pavlo Saik ◽  
Roman Dychkovskyi ◽  
Vasyl Lozynskyi ◽  
Volodymyr Falshtynskyi ◽  
Edgar Caseres Cabana ◽  
...  
Keyword(s):  
Gas Flow ◽  
Experimental Studies ◽  
Reaction Channel ◽  
Raw Material ◽  
Gas Generator ◽  
Equal Concentration ◽  
Gasification Process ◽  
Gasification Rate ◽  
Gasification Products ◽  
Gas Flow Velocity

The paper represents the studies of the process of carbonaceous raw material gasification. The initial material is represented by bituminous coal of grade H with the carbon (C) content of 79.2-85.3 %. Experimental studies have been used to substantiate the parameters of combustible generator gases (СО, Н2, СН4) output depending on the temperature of a reduction zone of the reaction channel and gas flow velocity along its length. It has been identified that the volume of the raw material input to be used for gasification process changes in direct proportion depending on the amount of burnt-out carbon and blow velocity. The gasification is intensified in terms of equal concentration of oxygen and carbon in the reaction channel of an underground gas generator. The gasification rate is stipulated by the intensity of chemical reactions, which depend immediately on the modes of blow mixture supply. Moreover, they depend directly on the intensity of oxygen supply to the coal mass and removal of the gasification products.

scholarly journals Modeling, optimization and experimental studies of supported nano-bimetallic catalyst for simultaneous total conversion of toluene and cyclohexane in air using a hybrid intelligent algorithm

RSC Advances ◽  
2018 ◽  
Vol 8 (31) ◽  
pp. 17346-17356 ◽  
Author(s):  
Mohammad Zabihi ◽  
Nasser Babajani
Keyword(s):  
Activated Carbon ◽  
Bimetallic Catalysts ◽  
Bimetallic Catalyst ◽  
Experimental Studies ◽  
Deep Oxidation ◽  
Intelligent Algorithm ◽  
Almond Shell ◽  
Total Conversion ◽  
Hybrid Intelligent Algorithm

This study reveals the simultaneous deep oxidation of toluene and cyclohexane over optimal supported bimetallic catalysts over almond shell based activated carbon.

scholarly journals ДОСЛІДЖЕННЯ ГІГІЄНІЧНИХ ВЛАСТИВОСТЕЙ МАТЕРІАЛІВ НАТІЛЬНОЇ ЛІКАРНЯНОЇ БІЛИЗНИ

2020 ◽  
Vol 140 (6) ◽  
pp. 38-47
Author(s):  
І. О. Іванов ◽  
Н. П. Супрун ◽  
Ю. О. Ващенко
Keyword(s):  
Comparative Analysis ◽  
Materials Science ◽  
Experimental Studies ◽  
Operating Conditions ◽  
Raw Material ◽  
Experimental Investigations ◽  
Textile Materials ◽  
Composition And Structure ◽  
Innovative Materials ◽  
Basic Functions

Investigation of the influence of the peculiarities of raw material composition and structure of traditional and innovative linen textile materials on their hygienic properties. Theoretical and experimental investigations are based on the main positions of textile materials science. In experimental studies, modern standardized methods for determining the hygienic properties of textile materials were used, as well as techniques specially developed taking into account the peculiarities of the operating conditions of underwear. The peculiarities of the operating conditions and the basic functions of hospital underwear were determined. The comparative analysis of hygienic properties of traditional and modern fabrics for underwear was carried out. Using the standardized and the developed methods, adapted to the peculiarities of the conditions of use of the products, the indicators characterizing the processes of water absorption of the materials were experimentally determined. On the basis of the obtained values of quality indicators, a comprehensive assessment of the ability of materials to transfer moisture and air, with the calculation of the arithmetic complex quality index was done. This allowed to determine the material that is optimal in properties, which provides thermophysiological comfort when operating hospital underwear. Using the developed methods, which take into account the specifics of the operating conditions, a comparative analysis of the hygienic properties of traditional and innovative materials for underwear was carried out. A new range of textile materials for underwear has been proposed, taking into account the peculiarities of the operational situation of consumption.

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