scholarly journals Activated Carbons from Fast Pyrolysis Biochar as Novel Catalysts for the Post-Treatment of Pyrolysis Vapors, Studied by Analytical Pyrolysis

2020 ◽  
Vol 6 (4) ◽  
pp. 65
Author(s):  
Taina Ohra-aho ◽  
Christian Lindfors ◽  
Juha Lehtonen ◽  
Tarja Tamminen ◽  
Virpi Siipola
Keyword(s):  
Activated Carbon ◽  
Active Sites ◽  
Activated Carbons ◽  
Degradation Products ◽  
High Surface ◽  
Fast Pyrolysis ◽  
Post Treatment ◽  
Mineral Contents ◽  
Surface Areas ◽  
Carbon Catalysts

Biochars are attractive materials for carbon catalysts since their carbon content and surface area are relatively high and minerals present in biochar can act as active sites for catalytic reactions. In this study, biochars from the fast pyrolysis of birch, pine, and unbarked willow were activated and acid washed. These materials were tested as catalysts for a post-treatment of pine wood pyrolysis vapors, aiming at stabilizing the vapors before their condensation. All the unmodified biochars had high content of minerals, those being highest in willow due to the bark. After the activation treatments, the surface areas and pore volumes of all biochars significantly increased. All studied biochars and activated carbon catalysts reduced the oxygen content of the pyrolysis degradation products. This effect was more pronounced for compounds derived from polysaccharides vs. lignin. The most promising catalyst for vapor upgrading was unwashed activated carbon from willow, having high surface areas and pore volumes together with high mineral contents. These properties together promoted the high conversion of polysaccharide-derived products (anhydrosugars, acids, and pyrans) into CO2. Release of highly oxidized degradation products may indicate that reductive stabilization takes place via hydrogen migration from the polysaccharide-derivatives to lignin derivatives, mediated by the carbon catalyst.

PREPARATION AND CHARACTERIZATION OF ACTIVATED CARBON FROM OIL PALM EMPTY FRUIT BUNCH WASTES USING ZINC CHLORIDE

2015 ◽  
Vol 74 (11) ◽  
Author(s):  
Riry Wirasnita ◽  
Tony Hadibarata ◽  
Abdull Rahim Mohd Yusoff ◽  
Zainab Mat Lazim
Keyword(s):  
Activated Carbon ◽  
Zinc Chloride ◽  
Oil Palm ◽  
Active Sites ◽  
Activated Carbons ◽  
Chemical Activation ◽  
Proximate Analysis ◽  
Infrared Spectrometry ◽  
Empty Fruit Bunch

An oil palm empty fruit bunch-derived activated carbon has been successfully produced by chemical activation with zinc chloride and without chemical activation. The preparation was conducted in the tube furnace at 500oC for 1 h. The surface structure and active sites of activated carbons were characterized by means of Fourier transform infrared spectrometry and field emission scanning electron microscopy. The proximate analysis including moisture content, ash content, bulk density, pH, and pH at zero charge was conducted to identify the psychochemical properties of the adsorbent. The results showed that the zinc chloride-activated carbon has better characteristics compared to the carbon without chemical activation.  

scholarly journals The Effects of Methane Storage Capacity Using Upgraded Activated Carbon by KOH

2018 ◽  
Vol 8 (9) ◽  
pp. 1596 ◽  
Author(s):  
Jung Park ◽  
Gi Lee ◽  
Sang Hwang ◽  
Ji Kim ◽  
Bum Hong ◽  
...  
Keyword(s):  
Surface Area ◽  
Storage Capacity ◽  
Activated Carbons ◽  
Chemical Activation ◽  
High Surface ◽  
Heat Of Adsorption ◽  
Low Grade ◽  
Surface Areas ◽  
Ch4 Adsorption ◽  
Ch4 Storage

In this study, a feasible experiment on adsorbed natural gas (ANG) was performed using activated carbons (ACs) with high surface areas. Upgraded ACs were prepared using chemical activation with potassium hydroxide, and were then applied as adsorbents for methane (CH4) storage. This study had three principal objectives: (i) upgrade ACs with high surface areas; (ii) evaluate the factors regulating CH4 adsorption capacity; and (iii) assess discharge conditions for the delivery of CH4. The results showed that upgraded ACs with surface areas of 3052 m2/g had the highest CH4 storage capacity (0.32 g-CH4/g-ACs at 3.5 MPa), which was over two times higher than the surface area and storage capacity of low-grade ACs (surface area = 1152 m2/g, 0.10 g-CH4/g-ACs). Among the factors such as surface area, packing density, and heat of adsorption in the ANG system, the heat of adsorption played an important role in controlling CH4 adsorption. The released heat also affected the CH4 storage and enhanced available applications. During the discharge of gas from the ANG system, the residual amount of CH4 increased as the temperature decreased. The amount of delivered gas was confirmed using different evacuation flow rates at 0.4 MPa, and the highest efficiency of delivery was 98% at 0.1 L/min. The results of this research strongly suggested that the heat of adsorption should be controlled by both recharging and discharging processes to prevent rapid temperature change in the adsorbent bed.

scholarly journals Sustainable Conversion of Agriculture and Food Waste into Activated Carbons Devoted to Fluoride Removal from Drinking Water in Senegal

2015 ◽  
Vol 8 (1) ◽  
pp. 8 ◽  
Author(s):  
Mohamad M. Diémé ◽  
Maxime Hervy ◽  
Saïdou N. Diop ◽  
Claire Gérente ◽  
Audrey Villot ◽  
...  
Keyword(s):  
Drinking Water ◽  
Activated Carbon ◽  
Activated Carbons ◽  
Public Health Problem ◽  
Calcium Content ◽  
Fluoride Removal ◽  
Carbonaceous Materials ◽  
Water Steam ◽  
Surface Areas ◽  
Fluoride Adsorption

<p>The objective of this study was to investigate the production of activated carbons (AC) from cashew shells, and millet stalks and their efficiency in fluoride retention. These agricultural residues are collected from Senegal. It is known that some regions of Sénégal, commonly called the groundnut basin, are affected by a public health problem caused by an excess of fluoride in drinking water used by these populations. The activated carbons were produced by a combined pyrolysis and activation with water steam; no other chemical compounds were added. Then, activated carbonaceous materials obtained from cashew shells and millet stalks were called CS-H<sub>2</sub>O and MS-H<sub>2</sub>O respectively. CS-H<sub>2</sub>O and MS-H<sub>2</sub>O show very good adsorbent features, and present carbon content ranges between 71 % and 86 %. The BET surface areas are 942 m² g<sup>-1</sup> and 1234 m².g<sup>-1</sup> for CS-H<sub>2</sub>O and MS-H<sub>2</sub>O respectively. A third activated carbon produced from food wastes and coagulation-flocculation sludge (FW/CFS-H<sub>2</sub>O) was produced in the same conditions. Carbon and calcium content of FW/CFS-H<sub>2</sub>O are 32.6 and 39.3 % respectively. The kinetics sorption were performed with all these activated carbons, then the pseudo-first equation was used to describe the kinetics sorption. Fluoride adsorption isotherms were performed with synthetic and natural water with the best activated carbon from kinetics sorption, Langmuir and Freundlich models were used to describe the experimental data. The results showed that carbonaceous materials obtained from CS-H<sub>2</sub>O and MS-H<sub>2</sub>O were weakly efficient for fluoride removal. With FW/CFS-H<sub>2</sub>O, the adsorption capacity is 28.48 mg.g<sup>-1 </sup>with r² = 0.99 with synthetic water.</p>

scholarly journals Preparation and characterization of activated carbons from albizia saman pod

2017 ◽  
Vol 36 (3) ◽  
pp. 44-53
Author(s):  
G. D. Akpen ◽  
M. I. Aho ◽  
N. Baba
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
Activated Carbons ◽  
High Surface ◽  
High Surface Area ◽  
Volatile Matter ◽  
Sieve Analysis ◽  
Albizia Saman ◽  
Temperature Surface

Activated carbon was prepared from the pods of Albizia saman for the purpose of converting the waste to wealth. The pods were thoroughly washed with water to remove any dirt, air- dried and cut into sizes of 2-4 cm. The prepared pods were then carbonised in a muffle furnace at temperatures of 4000C, 5000C, 6000C ,7000C and 8000C for 30 minutes. The same procedure was repeated for 60, 90, 120 and 150 minutes respectively. Activation was done using impregnationratios of 1:12, 1:6, 1:4, 1:3, and 1:2 respectively of ZnCl2 to carbonised Albizia saman pods by weight. The activated carbon was then dried in an oven at 1050C before crushing for sieve analysis. The following properties of the produced Albizia saman pod activated carbon (ASPAC) were determined: bulk density, carbon yield, surface area and ash, volatile matter and moisture contents. The highest surface area of 1479.29 m2/g was obtained at the optimum impregnation ratio, carbonization time and temperature of 1:6, 60 minutes and 5000C respectively. It was recommended that activated carbon should be prepared from Albizia saman pod with high potential for adsorption of pollutants given the high surface area obtained.Keywords: Albizia saman pod, activated carbon, carbonization, temperature, surface area

scholarly journals Waste biomass as sources for activated carbon production-A review

2013 ◽  
Vol 47 (4) ◽  
pp. 347-364 ◽  
Author(s):  
MS Islam ◽  
MA Rouf
Keyword(s):  
Activated Carbon ◽  
Process Parameters ◽  
Activated Carbons ◽  
Low Cost ◽  
Process Conditions ◽  
Waste Biomass ◽  
Active Carbons ◽  
Carbon Production ◽  
Surface Areas ◽  
Physical And Chemical

A review of the production of activated carbons from waste biomass has been presented. The effects of various process parameters on the pyrolysis stage have been reviewed. Influences of activating conditions, physical and chemical, on the active carbon properties have been discussed. Under certain process conditions several active carbons with BET surface areas, ranging between 250 and 2410 m2/g and pore volumes of 0.022 and 91.4 cm3/g, have been produced. A comparison in characteristics and uses of activated carbons from waste biomass with those of commercial carbons has been made. Waste biomass being highly efficient, low cost and renewable sources of activated carbon production. Bangladesh J. Sci. Ind. Res. 47(4), 347-364, 2012 DOI: http://dx.doi.org/10.3329/bjsir.v47i4.14064

Adsorption of Soluble Metal Ions from Red Mud by Modified Activated Carbon

2008 ◽  
Vol 368-372 ◽  
pp. 1541-1544 ◽  
Author(s):  
Hua Lei Zhou ◽  
Dong Yan Li ◽  
Guo Zhuo Gong ◽  
Ya Jun Tian ◽  
Yun Fa Chen
Keyword(s):  
Activated Carbon ◽  
Metal Ions ◽  
Adsorption Capacity ◽  
Red Mud ◽  
Activated Carbons ◽  
Valuable Metal ◽  
Surface Areas ◽  
Alumina Industry ◽  
Modified Activated Carbons ◽  
Almost All

Activated carbon was employed as the adsorption carrier for the metal ions in HCl solution of red mud, a solid waste produced in alumina industry. To improve the adsorption capacity to valuable metal ions, the activated carbon was modified by chemicals including HNO3, H2O2, H2SO4, H3PO4, NH3, Na2CO3, and tri-butyl phosphate (TBP). It was found that the modifications contributed the high adsorption capacity to almost all metal ions we focused on. In the case of TBP, remarkably higher adsorption capacity and selectivity of Sc3+ was observed. The correlation between the surface areas, IR spectra of those chemically modified activated carbons and adsorption was schemed.

Effect of Activating Agent on the Preparation of Bamboo-Based High Surface Area Activated Carbon by Microwave Heating

2016 ◽  
Vol 35 (6) ◽  
pp. 535-541 ◽  
Author(s):  
Hongying Xia ◽  
Jian Wu ◽  
Chandrasekar Srinivasakannan ◽  
Jinhui Peng ◽  
Libo Zhang
Keyword(s):  
Activated Carbon ◽  
Microwave Heating ◽  
Surface Area ◽  
Pore Volume ◽  
Activated Carbons ◽  
High Surface ◽  
High Surface Area ◽  
Significant Proportion ◽  
Mixture Ratio ◽  
Activating Agent

AbstractThe present work attempts to convert bamboo into a high surface area activated carbon via microwave heating. Different chemical activating agents such as KOH, NaOH, K2CO3 and Na2CO3 were utilized to identify a most suitable activating agent. Among the activating agents tested KOH was found to generate carbon with the highest porosity and surface area. The effect of KOH/C ratio on the porous nature of the activated carbon has been assessed. An optimal KOH/C ratio of 4 was identified, beyond which the surface area as well as the pore volume were found to decrease. At the optimized KOH/C ratio the surface area and the pore volume were estimated to be 3,441 m2/g and 2.093 ml/g, respectively, with the significant proportion of which being microporous (62.3%). Activated carbon prepared under the optimum conditions was further characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Activated carbons with so high surface area and pore volume are very rarely reported, which could be owed to the nature of the precursor and the optimal conditions of mixture ratio adopted in the present work.

A comparison of different activated carbon performances on catalytic ozonation of a model azo reactive dye

2012 ◽  
Vol 66 (1) ◽  
pp. 179-184 ◽  
Author(s):  
Ş. Gül ◽  
O. Eren ◽  
Ş. Kır ◽  
Y. Önal
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
Activated Carbons ◽  
High Surface ◽  
High Surface Area ◽  
Reactive Dye ◽  
Catalytic Ozonation ◽  
Bet Surface Area ◽  
Solution Ph ◽  
Pore Properties

The objective of this study is to compare the performances of catalytic ozonation processes of two activated carbons prepared from olive stone (ACOS) and apricot stone (ACAS) with commercial ones (granular activated carbon-GAC and powder activated carbon-PAC) in degradation of reactive azo dye (Reactive Red 195). The optimum conditions (solution pH and amount of catalyst) were investigated by using absorbencies at 532, 220 and 280 nm wavelengths. Pore properties of the activated carbon (AC) such as BET surface area, pore volume, pore size distribution, and pore diameter were characterized by N2 adsorption. The highest BET surface area carbon (1,275 m2/g) was obtained from ACOS with a particle size of 2.29 nm. After 2 min of catalytic ozonation, decolorization performances of ACOS and ACAS (90.4 and 91.3%, respectively) were better than that of GAC and PAC (84.6 and 81.2%, respectively). Experimental results showed that production of porous ACs with high surface area from olive and apricot stones is feasible in Turkey.

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