Alteration of Chemical Structure of the Active Vegetal Coals

2008 ◽  
Vol 59 (2) ◽  
pp. 159-164
Author(s):  
Raisa Nastas ◽  
Vasile Rusu ◽  
Maria Giurginca ◽  
Aurelia Meghea ◽  
Tudor Lupascu
Keyword(s):  
Functional Groups ◽  
Activated Carbons ◽  
Raw Materials ◽  
Chemical Activation ◽  
Ftir Spectra ◽  
Active Carbons ◽  
Grape Seeds ◽  
Carboxylic Groups ◽  
Acidic Sites ◽  
Sulfurous Anhydride

The peculiarities of surface chemistry, functional groups and acid-basic properties of activated carbons obtained from vegetal raw materials by different methods of activation have been emphasized. Active carbons obtained from peach and plum stones by physical-chemical activation (with steam, aqueous solutions of sulfurous anhydride or ammonia) possess predominantly basic functional groups on the surface, although acidic sites in minor quantities are also accumulated. FTIR spectra suggest the presence on the surface of these carbons of alcoholic and phenolic groups, quinones and hydroxy-ketones. Active carbons obtained from plum stones, nut shells and grape seeds by chemical activation with phosphoric acid possess predominantly acidic functional groups on the surface, out of which carboxylic groups are prevailing by 2-3 times the content of phenolic structures. FTIR spectra suggest the presence on the surface of these carbons of a series of organic structures including carboxylic acids, ketones, aldehydes, quinones, lactones and esters, also alcohols and phenols. UV-VIS-NIR spectra also indicate the presence of alcohols and phenols on the surface of these carbons.

scholarly journals ON THE POSSIBILITY OF USING CARBON ENTEROSORBENTS TO NORMALIZE CHOLESTEROL METABOLISM

2021 ◽  
Vol 14 (4) ◽  
pp. 64-69
Author(s):  
N. V. Sych ◽  
Keyword(s):  
Cholesterol Metabolism ◽  
Activated Carbons ◽  
Raw Materials ◽  
Chemical Activation ◽  
Density Lipoprotein ◽  
Sorption Isotherms ◽  
The Body ◽  
Blood Cholesterol ◽  
Carbon Adsorbents ◽  
Industrial Carbon

The creation of effective drugs for the prevention and treatment of atherosclerosis is one of the urgent interdisciplinary tasks for modern chemistry and pharmacology. Given the role of hypercholesterolemia in the development of this disease, it is necessary to remove excess amounts of cholesterol from the body. As an alternative to means of lowering total cholesterol and low-density lipoprotein (LDL) cholesterol, the possibility of using carbon enterosorbents for efferent therapy is considered. Aim. The purpose of the study was to evaluate the sorption capacity of the adsorbents developed by authors in terms of the possibility of cholesterol adsorption. Methods. Using the spectrophotometric method, the sorption of cholesterol on samples of adsorbents obtained by chemical activation of waste from the processing of lignocellulosic raw materials — dogwood and coffee residue has been studied. Results. A comparison of sorption isotherms with the isotherm obtained on the industrial adsorbent SORBEX has been performed. It was shown that the adsorption capacity of carbon adsorbents is primarily determined by their porous structure. The highest sorption values (7,3 mg/g) have been revealed by the sorption material obtained by chemical activation of cornel seed, an intermediate position (6,3 mg/g) is occupied by the adsorbent obtained from the coffee residue. Industrial carbon SORBEX has the lowest sorption values (5,3 mg/g). Conclusions. Calculations by Langmuir’s and Freundlich’s models testify about the accordance of the experimental data to Langmuir’s model. The use of the obtained activated carbons may be one of the effective alternative ways to lower blood cholesterol.

Development and Application of Bamboo Activated Carbons and their Potency as Adsorbent Material for Adsorbed Natural Gas (ANG); An Overview

2016 ◽  
Vol 705 ◽  
pp. 126-130 ◽  
Author(s):  
Dewa Ngakan Ketut Putra Negara ◽  
Tjokorda Gde Tirta Nindhia ◽  
I Wayan Surata ◽  
Made Sucipta
Keyword(s):  
Activated Carbon ◽  
Natural Gas ◽  
Activated Carbons ◽  
Raw Materials ◽  
Chemical Activation ◽  
Industrial Sector ◽  
Production Costs ◽  
Adsorbed Natural Gas ◽  
High Production

Currently, the use of activated carbon (AC) increased significantly for the industrial sector, health, environment and agriculture. However, the commercial price of activated carbon is relatively expensive, especially for micro industries mainly due to high production costs. Additionally, it comes from non-renewable sources with limited availability. This prompted the researchers to study the production of AC from inexpensive precursors and renewable; one of which is made from bamboo. AC production can be done through a pyrolysis process followed by physical or chemical activation. Differences in raw materials and activation methods used can affect the characteristics and quality of activated carbon produced. This paper reviews the development and application of bamboo activated carbons in the life sectors and their potency for use as an adsorbent material for the absorbed natural gas (ANG).

scholarly journals STUDY OF RECEIVING WOOD AND PLANT PLASTICS WITHOUT BINDERS IN THE PRESENCE OF CATALYSTS OF POLYOXOMETALLATES TYPE

2018 ◽  
Vol 8 (1) ◽  
pp. 132-138
Author(s):  
Виктор Бурындин ◽  
Viktor Buryndin ◽  
Лариса Бельчинская ◽  
Larisa Belchinskaya ◽  
Андрей Савиновских ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Functional Groups ◽  
Hot Pressing ◽  
Raw Materials ◽  
Flexural Modulus ◽  
Chemical Activation ◽  
Physical And Mechanical Properties ◽  
Strength Properties ◽  
Raw Material ◽  
Plastic Properties

The possibility of obtaining wood and plant plastics without a binder (WP-WB) in the presence of a catalyst of man-ganese-containing sodium vanadomolybdophosphate has been investigated. The use of this catalyst makes it possible to reduce the temperature of hot pressing in closed molds from 1,800°C to 1,600°C. The fractional composition of the initial press raw material influences physical and mechanical properties of WP-WB. Higher values of the plastic properties are obtained by using a 0.7 mm fraction, which is associated with an increased specific surface area of the particles compared to 1.3 mm particles. The results has showed that the samples obtained by using the catalyst have increase in strength properties (flexural strength, flexural modulus, hardness) at lower pressing temperature, but reduction of water resistance performance has been observed . This is explained by the increase in the content of functional groups when using a catalyst. The process of obtaining plastic can be broken down into two successive stages: the first is hydrothermal destruction of lignin-carbohydrate complex (initial moisture of the press raw material is 12%, the temperature of hot pressing in closed molds is 160 ... .180 ° C) and partial chemical activation of lignin as a result of hydrogen peroxide and catalyst application; the second stage - formation of plastic with the formation of a network structure due to the formed functional groups. It is established that the values of physical and mechanical properties of WP-WB are higher than those of plastic obtained on the basis of plant raw materials (PP-WB). This can be explained by the fact that lignin of coniferous species has the guaiacylpropane structure, while plant raw material has a hydroxyphenylpropane structure

Production of High Surface Area Activated Carbon from Coconut Husk

2014 ◽  
Vol 1644 ◽  
Author(s):  
Paul R. Armstrong ◽  
Zachary J. Morchesky ◽  
Dustin T. Hess ◽  
Kofi W. Adu ◽  
David. K. Essumang ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
Activated Carbons ◽  
Raw Materials ◽  
Chemical Activation ◽  
High Surface ◽  
Waste Product ◽  
High Surface Area ◽  
Coconut Husk ◽  
Porosity Analysis

ABSTRACTWe present preliminary results on a processing protocol by chemical activation that transforms organic waste product such as coconut husk into high surface area activated carbon. Dried raw materials of the coconut husk were carbonized anaerobically into char. The char was impregnated with KOH of different ratios and were activated at 800°C and 900°C. The transmission electron microscope was used to acquire structural and morphological information of the activated carbon, and the surface area and porosity analysis were performed using Micromeritics ASAP 2020 analyzer. The activated carbons show both micropores and mesopores with specific surface area as high as 2900m2/g.

scholarly journals Preparation and Characterization of Activated Carbon Obtained from Water Treatment Plant Sludge for Removal of Cationic Dye from Wastewater

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1549
Author(s):  
Alaor Valério Filho ◽  
Raíssa Xavaré Kulman ◽  
Luana Vaz Tholozan ◽  
André Ricardo Felkl de Almeida ◽  
Gabriela Silveira da Rosa
Keyword(s):  
Water Treatment ◽  
Activated Carbons ◽  
Chemical Activation ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Mesoporous Structure ◽  
Carboxylic Groups ◽  
In The Beginning ◽  
Water Treatment Plant Sludge

The proposal of this work was the preparation and characterization of activated carbons obtained from water treatment plant sludge (WTS) to apply as adsorbents in the removal of organic dye contaminants from wastewater. The activated carbons were produced with a combination of chemical activation and pyrolysis processes. The textural characteristics of both adsorbents presented a satisfactory superficial area and mesoporous structure. The presence of phenolic and carboxylic groups in the surface indicated a better adsorption of cationic adsorbates. When applied as adsorbents in the removal of methylene blue (MB) from wastewater, the maximum removal values obtained were up to 96%. The adsorption results showed that the adsorption was faster in the beginning and reached maximum around 30 min. The Elovich kinetic model and the Sips isotherm model presented the best fit to experimental data, which was checked by analysis of variance (ANOVA). The production of activated carbons from WTS is a sustainable and effective option in the removal of MB dye.

scholarly journals Reclamation Of Plant Wastes (Straw) And Obtaining (Nano) Chips With Bactericidal Properties Based On Them

2015 ◽  
Vol 61 (3) ◽  
pp. 1-7
Author(s):  
Voropaeva Nadezda Leonidovna ◽  
Viktor Mikhailovich Mukhin ◽  
Revina Alexandra Anatolyevna ◽  
Busev Sergey Alekseevich ◽  
Karpachev Vladimir Vladimirovich
Keyword(s):  
Silver Nanoparticles ◽  
Crop Residues ◽  
Activated Carbons ◽  
Raw Materials ◽  
Field Tests ◽  
Jerusalem Artichoke ◽  
Nano Particles ◽  
Agricultural Crop ◽  
Active Carbons ◽  
Carbonaceous Sorbents

Abstract Rape, camelina, wheat and Jerusalem artichoke vegetable wastes (straw) as annually renewable raw materials were processed into activated carbons, which were modified with silver nanoparticles for carbonaceous sorbents to acquire specific properties, since carbonaceous sorbents are usually widely used in the food industry, agriculture, medicine and other fields of human activity. The technology to obtain active carbons from agricultural crop residues has been developed, active carbon physico-chemical and adsorption properties, textural characteristics have been studied, new functional carbon (nano) materials with antibacterial activity containing (nano) particles of silver have been obtained, their influence within (nano) chip composition on rape crop growth, development and yield has been studied. In the conducted field tests, the highest activity was noted when using the (nano) chip whose structure included RAC - camelina and silver nanoparticles. Besides, when nano chips are used for seed treatment, the yield increase makes up 11.6 % for nanoparticles containing Ag, for plant active carbons (PAC) (rape) with Ag this index makes up 28.1 %, for RAC (Camelina) with Ag it makes up 55.8 % (compared to the control variant), which can be explained by the differences in the sorption characteristics of the studied radio activated carbons. Our results and the previous studies of other authors can prove the fact that silver nanoparticles (including those being a part of (nano) chips) “get” into the biochemical processes and have a pronounced phytostimulating effect on plants, which was especially obvious when suppressing the activity of plant pathogenic microflora by silver nanoparticles.

scholarly journals Activated Carbons Derived from Teak Sawdust-Hydrochars for Efficient Removal of Methylene Blue, Copper, and Cadmium from Aqueous Solution

Water ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2581 ◽  
Author(s):  
Hai Duy Nguyen ◽  
Hai Nguyen Tran ◽  
Huan-Ping Chao ◽  
Chu-Ching Lin
Keyword(s):  
Methylene Blue ◽  
Surface Area ◽  
Functional Groups ◽  
Activated Carbons ◽  
Electrostatic Force ◽  
Chemical Activation ◽  
Hydrothermal Process ◽  
Weight Ratio ◽  
Activation Process ◽  
Complexation Reaction

Recycling materials from waste has been considered one of the essential principles in the context of sustainable development. In this study, we used teak sawdust as the feedstock material to synthesize activated carbon (AC) samples and evaluated the application of these ACs in the adsorption of methylene blue (MB), Cd(II), and Cu(II). The sawdust was carbonized by a hydrothermal process, followed by chemical activation using K2CO3 or ZnCl2 in various weight ratios. The AC samples produced were characterized by scanning electron microscopy, Brunauer–Emmett–Teller surface area analysis, Fourier-transform infrared spectroscopy, X-ray photon spectroscopy, and mass titration of acidic groups. The characterization results showed that the ACs did possess a high surface area and rich oxygen-containing functional groups. The adsorptive amounts of MB, Cd(II), and Cu(II) on ACs approximately increased with the concentration of the activating agent: when the weight ratio of the carbonaceous material to ZnCl2 reached 1.75, the maximum adsorption capacities for MB, Cd(II), and Cu(II) were achieved, and the values were 614, 208, and 182 mg/g, respectively. The level of oxygen-containing functional groups was identified as an important factor in determining the adsorptive amounts. While the electrostatic force was the primary pathway that led to the adsorption of the tested contaminants onto the AC, the complexation reaction was a vital mechanism responsible for the adsorptive interaction between ACs and Cu(II). The high adsorption capacity of the synthetic ACs for MB, Cd(II), and Cu(II) demonstrated in this study points out the potential application of biomass-residue-based adsorbents prepared via a coupled hydrothermal carbonization/chemical activation process in wastewater treatment.

scholarly journals Comparative Study on the Adsorption Capacity of Activated Carbon Prepared from Lapsi Seed Stone and Betel nut using Phosphoric Acid

2018 ◽  
Vol 13 (1) ◽  
pp. 153-159
Author(s):  
Sahira Joshi
Keyword(s):  
Activated Carbon ◽  
Comparative Study ◽  
Iodine Number ◽  
Adsorption Capacity ◽  
Functional Groups ◽  
Activated Carbons ◽  
Chemical Activation ◽  
Betel Nut ◽  
Surface Functional Groups ◽  
Methylene Blue Number

 This paper presents the comparative study on the adsorption capacity of activated carbons prepared from Lapsi (Choerospondias axillaris) seed stone and Betel (Areca catechu) nut. Activated carbons (ACs) were prepared from Lapsi seed stone (LSS) and Betel Nut (BN) by chemical activation with H3PO4 (in the ratio of 1:1 by weight) at 400°C. The pore structure of activated carbons was determined by iodine number and methylene blue number. Surface morphology of ACs was studied by scanning electron microscopy (SEM). Surface functional groups were analyzed by Fourier Transform Infra Red Spectroscopy (FTIR). As indicated by TGA analysis, the appropriate temperature required for carbonization was 400 ºC. Betel nut AC showed high iodine number and methylene number of 888 mg/gm and 369 mg/gm respectively. SEM micrographs of Betel nut AC show the presence of well developed pores on its surface. FTIR result indicated that both ACs contain −OH, >C=O groups as oxygen containing surface functional groups. Based on the result, the AC prepared from betel nut by activation with H3PO4 is comparable with commercial activated carbon and could be used as potential adsorbent for removal of pollutants from water and waste water.Journal of the Institute of Engineering, 2017, 13(1): 153-159

scholarly journals Low-Cost Activated Grape Seed-Derived Hydrochar through Hydrothermal Carbonization and Chemical Activation for Sulfamethoxazole Adsorption

2019 ◽  
Vol 9 (23) ◽  
pp. 5127 ◽  
Author(s):  
Elena Diaz ◽  
Francisco Javier Manzano ◽  
John Villamil ◽  
Juan Jose Rodriguez ◽  
Angel F. Mohedano
Keyword(s):  
Surface Composition ◽  
Activated Carbons ◽  
Low Cost ◽  
Chemical Activation ◽  
Hydrothermal Carbonization ◽  
Grape Seed ◽  
Bet Surface Area ◽  
Grape Seeds ◽  
Porous Texture ◽  
Surface Areas

Activated carbons were prepared by chemical activation with KOH, FeCl3 and H3PO4 of the chars obtained via hydrothermal carbonization of grape seeds. The hydrochars prepared at temperatures higher than 200 °C yielded quite similar proximate and ultimate analyses. However, heating value (24.5–31.4 MJ·kg−1) and energy density (1.04–1.33) significantly increased with carbonization temperatures between 180 and 300 °C. All the hydrochars showed negligible BET surface areas, while values between 100 and 845 m2·g−1 were measured by CO2 adsorption at 273 K. Activation of the hydrochars with KOH (activating agent to hydrochar ratio of 3:1 and 750 °C) led to highly porous carbons with around 2200 m2·g−1 BET surface area. Significantly lower values were obtained with FeCl3 (321–417 m2·g−1) and H3PO4 (590–654 m2·g−1), showing these last activated carbons important contributors to mesopores. The resulting materials were tested in the adsorption of sulfamethoxazole from aqueous solution. The adsorption capacity was determined by the porous texture rather than by the surface composition, and analyzed by FTIR and TPD. The adsorption equilibrium data (20 °C) fitted the Langmuir equation well. The KOH-activated carbons yielded fairly high saturation capacity reaching up to 650 mg·g−1.

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