scholarly journals Effects of Gasifying Agents on the Characterization of Nut Shell-derived Activated Carbon

1995 ◽  
Vol 12 (3) ◽  
pp. 247-258 ◽  
Author(s):  
C. Nguyen ◽  
A. Ahmadpour ◽  
D.D. Do

Activated carbon was prepared from nut shells using a conventional two-stage method: carbonization followed by activation. Activation with steam or carbon dioxide as activating agent produced a range of chars of different burn-off. These were characterized for their total and micropore surface areas, and benzene adsorption capacity. Benzene adsorption measurement provided an insight into the effect of porosity development on the adsorptive properties of the adsorbent. It was found that activated carbon products from nut shells were comparable, in terms of adsorption characteristics, with activated carbons from other lignocellulosic precursors. The evolution of porosity of the resulting carbons shows that carbon dioxide is the preferable agent for the production of activated carbon with a narrow micropore size distribution.

1997 ◽  
Vol 15 (1) ◽  
pp. 59-68 ◽  
Author(s):  
Th. El-Nabarawy ◽  
M.R. Mostafa ◽  
A.M. Youssef

Non-activated carbon ‘A’, physically-activated carbons P1–P4, zinc chloride-activated carbons Z1–Z4 and potassium sulphide-activated carbons K1–K4 were prepared from Maghara coal (Sinai, Egypt). The surface areas of these carbons were determined by investigating the adsorption of carbon dioxide at 298 K and of nitrogen at 77 K. The decolourization powers of the carbons were determined from methylene blue adsorption at 308 K. The adsorption of methanol, benzene, n-hexane, n-octane and α-pinene at 308 K was also determined using equilibrium and flow techniques. The removal of ammonia and phenol from water was investigated on some selected samples. The activated carbons showed high capacities towards the removal of organic pollutants from water and from gas streams via adsorption. Their capacity towards a particular pollutant depends on the method of activation and is related to the textural and/or the chemistry of the carbon surface.


2017 ◽  
Vol 19 (2) ◽  
pp. 44-50 ◽  
Author(s):  
Jarosław Serafin

Abstract The objective of this work was preparation of activated carbon from spent dregs for carbon dioxide adsorption. A saturated solution of KOH was used as an activating agent. Samples were carbonized in the furnace at the temperature of 550°C. Textural properties of activated carbons were obtained based on the adsorption-desorption isotherms of nitrogen at −196°C and carbon dioxide at 0°C. The specific surface areas of activated carbons were calculated by the Brunauer – Emmett – Teller equation. The volumes of micropores were obtained by density functional theory method. The highest CO2 adsorption was 9.54 mmol/cm3 at 0°C – and 8.50 mmol/cm3 at 25°C.


2013 ◽  
Vol 821-822 ◽  
pp. 1307-1312
Author(s):  
Xin Yu Cui ◽  
Jian Min Gao ◽  
Xin Min Hao ◽  
Jin Ju Sun ◽  
Tian Ma ◽  
...  

Activated carbons are prepared from hemp stem with KOH as activating agent under different ratio of KOH to carbon conditions. The BET(Brunauer Emmett and Teller) specific surface area of the hemp stem-based activated carbons first increases and then decreases with the increasing ratio of KOH to carbon. The specific surface area, micropore surface area and volume of the activated carbons reach a maximum of 1589.27m2/g 1420.52m2/g, 89% of the total area, 0.751m3/g at the ratio of 4.5:1. The micropore size distribution shows the activated carbons contain a large number of ultramicropore and supermicropore.


2010 ◽  
Vol 636-637 ◽  
pp. 1383-1388
Author(s):  
J.M. Valente Nabais ◽  
Carlos Laginhas ◽  
Peter J.M. Carrott ◽  
Manuela M.L. Ribeiro Carrott ◽  
Cristina Galacho ◽  
...  

The surface characterisation of new activated carbons produced from tire residues by activation with carbon dioxide was studied. The activated carbons produced were mainly basic with point of zero charge values above 8.8. The main surface functional groups identified by FTIR were ether, quinones, lactones, ketones, hydroxyls (free and phenol) and pyrones. The XRD analysis shows that the materials produced have a microstructural organisation with microcrystallite height around 1.5nm and width from 3 to 5.3nm. This analysis indicates also the possible presence of oxides (single or mixture) of the following heteroatoms: Fe, Al, Ca, Mg, Ti, Si, K, Pb, Cd, Ba, Zn and Sn. The results have shown the significant potential of this type of residues for activated carbon production. Furthermore, the environment friendly use of an industrial residue is also noteworthy.


2015 ◽  
Vol 74 (11) ◽  
Author(s):  
Riry Wirasnita ◽  
Tony Hadibarata ◽  
Abdull Rahim Mohd Yusoff ◽  
Zainab Mat Lazim

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.  


2014 ◽  
Vol 9 (1) ◽  
pp. 166-174 ◽  
Author(s):  
Rajeshwar M. Shrestha ◽  
Margit Varga ◽  
Imre Varga ◽  
Amar P. Yadav ◽  
Bhadra P. Pokharel ◽  
...  

Activated carbons were prepared from Lapsi seed stone by the treatment with H2SO4 and HNO3 for the removal of Ni (II) ions from aqueous solution. Two activated carbon have been prepared from Lapsi seed stones by treating with conc.H2SO4 and a mixture of H2SO4 and HNO3 in the ratio of 1:1 by weight for removal of Ni(II) ions. Chemical characterization of the resultant activated carbons was studied by Fourier Transform Infrared Spectroscopy and Boehm titration which revealed the presence of oxygen containing surface functional groups like carboxyl, lactones and phenols in the carbons. The optimum pH for nickel adsorption is found to be 5. The adsorption data were better fitted with the Langmuir equations than Freundlich adsorption equation to describe the equilibrium isotherms. The maximum adsorption capacity of Ni (II) on the resultant activated carbons was 28.25.8 mg g-1 with H2SO4 and 69.49 mg g-1 with a mixture of H2SO4 and HNO3. The waste material used in the preparation of the activated carbons is inexpensive and readily available. Hence the carbons prepared from Lapsi seed stones can act as potential low cost adsorbents for the removal of Ni (II) from water. DOI: http://dx.doi.org/10.3126/jie.v9i1.10680Journal of the Institute of Engineering, Vol. 9, No. 1, pp. 166–174


2015 ◽  
Vol 8 (1) ◽  
pp. 8 ◽  
Author(s):  
Mohamad M. Diémé ◽  
Maxime Hervy ◽  
Saïdou N. Diop ◽  
Claire Gérente ◽  
Audrey Villot ◽  
...  

<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>


2017 ◽  
Vol 36 (3) ◽  
pp. 44-53
Author(s):  
G. D. Akpen ◽  
M. I. Aho ◽  
N. Baba

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


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