scholarly journals Acetic acid adsorption onto activated carbon derived from pods of Acacia nilotica var astringens (Sunt tree) by chemical activation with ZnCl2

2015 ◽  
Vol 5 (10) ◽  
pp. 42-48
Author(s):  
Mutasim H. Elhussien ◽  
◽  
Isa Yusuf Makarfi ◽  

The purpose of this study is to prepare and investigate the adsorption behavior of acetic acid onto two samples of activated carbon prepared from Acacia nilotica var astringens, Sunt tree,( SUNT-C1 and SUNT-C2). Applicability Langmuir, Freundlich, Temkin and Dubinin-Radushkevitch models of adsorptions isotherm have been tested, while acetic acid initial concentration varied between (0.010 – 0.300) mol/dm3. A comparative study of adsorption capacities of these samples was performed. The obtained data were compared and fitted well with the four models; there exist a correlation between physico- chemical properties of the activated carbons and the sorption processes. The maximum monolayer coverage (Qo) from Langmuir isotherm model was determined to be 1.016mg/g. Also from Freundlich Isotherm model, the sorption intensity (n) which indicates favourable sorption and the correlation value are 1.11 and 1.09 respectively.

2016 ◽  
Vol 855 ◽  
pp. 137-142
Author(s):  
Piyarut Moonsri ◽  
Wilaiporn Pongpian ◽  
Kristiya Moonsri

This research studied production of activated carbon (AC) derived from tamarind pods damaged by mold. Folk wisdom kiln which manufactured from an oil tank size of 200 L was used for pyrolysis and carbonization of tamarind pod derived from sweet and sour tamarinds. The AC was produced by using chemical activation and thermal activation at the optimal condition. Then the physical and chemical properties of the AC were investigated. From the study, it was found that optimal condition for charcoal carbonization of the tamarind pod was 400 °C for 4 hrs. The optimal condition for thermal activation was 600 °C for 1-2 hrs. The phosphoric acid (H3PO4) showed higher effectiveness for activation than distillation water (H2O), potassium hydroxide (KOH) and zinc chloride (ZnCl2). The produced AC has specific surface area of 851.58-910.31 m2/g (BET Theory), a pore volume of 2.24-2.32 cm3/g with an average pore radius of 50.90 to 52.53 Å, iodine number of 613.9-654.8 mg/g, phenols adsorption of 61.7-83.1% and apparent density 0.4528 g/cm3. The results from proximate analysis shown that the AC has the moisture content of 6.81-7.54% (wt), the ash content of 6.58-7.31% (wt), the volatile matter of 38.26-40.12% (wt) and the fixed carbon of 52.57-55.16% (wt). The performance of the AC for acetic acid adsorption according to the Langmuir and Freundlich isotherm exhibited a monolayer adsorption isotherm and the AC adsorbed the acetic acid well and strength. Therefore the produced AC can be further used for filter material in small water treatment.


Author(s):  
Davoud Balarak ◽  
Fatemeh Bandani ◽  
Zaccheus Shehu ◽  
Nehad J. Ahmed

Equilibrium sorption of the Thermally Treated Rice Husk (TTRH) for Sulfamethazine (SMT) adsorption was studied. The Physico-chemical properties of the modified rice husk were determined. The equilibrium sorption data were fitted into Langmuir, Freundlich and Dubinin–Radushkevich isotherms. Of the three adsorption isotherm, the R2 value of Langmuir isotherm model was the highest. Also compared to other isotherms the AARE coefficient for the Langmuir isotherm is low, which indicates favorable sorption. The maximum monolayer coverage (qm) from Langmuir isotherm model was determined to be 19.11 mg/g, the separation factor indicating a favorable sorption experiment is 0.446. Also from Freundlich Isotherm model, the sorption intensity (n) which indicates favorable sorption and the correlation value are 1.84 and 3.79 respectively. The mean free energy was estimated from Dubinin–Radushkevich isotherm model to be 9.18 KJ/mol which clearly proved that the adsorption experiment followed a physical process.


2017 ◽  
Vol 19 (4) ◽  
pp. 87-93 ◽  
Author(s):  
Diana P. Vargas ◽  
Liliana Giraldo ◽  
Juan Carlos Moreno-Piraján

Abstract The effect of textural and chemical properties such as: surface area, pore volume and chemical groups content of the granular activated carbon and monoliths on phenol adsorption in aqueous solutions was studied. Granular activated carbon and monolith samples were produced by chemical activation. They were characterized by using N2 adsorption at 77 K, CO2 adsorption at 273 K, Boehm Titrations and immersion calorimetry in phenol solutions. Microporous materials with different pore size distribution, surface area between 516 and 1685 m2 g−1 and pore volumes between 0.24 and 0.58 cm3 g−1 were obtained. Phenol adsorption capacity of the activated carbon materials increased with increasing BET surface area and pore volume, and is favored by their surface functional groups that act as electron donors. Phenol adsorption capacities are in ranged between 73.5 and 389.4 mg · g−1.


Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2951
Author(s):  
Mirosław Kwiatkowski ◽  
Jarosław Serafin ◽  
Andy M. Booth ◽  
Beata Michalkiewicz

This paper presents the results of a computer analysis of the effect of activation process temperature on the development of the microporous structure of activated carbon derived from the leaves of common polypody (Polypodium vulgare) via chemical activation with phosphoric acid (H3PO4) at activation temperatures of 700, 800, and 900 °C. An unconventional approach to porous structure analysis, using the new numerical clustering-based adsorption analysis (LBET) method together with the implemented unique gas state equation, was used in this study. The LBET method is based on unique mathematical models that take into account, in addition to surface heterogeneity, the possibility of molecule clusters branching and the geometric and energy limitations of adsorbate cluster formation. It enabled us to determine a set of parameters comprehensively and reliably describing the porous structure of carbon material on the basis of the determined adsorption isotherm. Porous structure analyses using the LBET method were based on nitrogen (N2), carbon dioxide (CO2), and methane (CH4) adsorption isotherms determined for individual activated carbon. The analyses carried out showed the highest CO2 adsorption capacity for activated carbon obtained was at an activation temperature of 900 °C, a value only slightly higher than that obtained for activated carbon prepared at 700 °C, but the values of geometrical parameters determined for these activated carbons showed significant differences. The results of the analyses obtained with the LBET method were also compared with the results of iodine number analysis and the results obtained with the Brunauer–Emmett–Teller (BET), Dubinin–Radushkevich (DR), and quenched solid density functional theory (QSDFT) methods, demonstrating their complementarity.


2012 ◽  
Vol 1 (3) ◽  
pp. 75 ◽  
Author(s):  
W.D.P Rengga ◽  
M. Sudibandriyo ◽  
M Nasikin

Gas storage is a technology developed with an adsorptive storage method, in which gases are stored as adsorbed components on the certain adsorbent. Formaldehyde is one of the major indoor gaseous pollutants. Depending on its concentration, formaldehyde may cause minor disorder symptoms to a serious injury. Some of the successful applications of technology for the removal of formaldehyde have been reported. However, this paper presents an overview of several studies on the elimination of formaldehyde that has been done by adsorption method because of its simplicity. The adsorption method does not require high energy and the adsorbent used can be obtained from inexpensive materials. Most researchers used activated carbon as an adsorbent for removal of formaldehyde because of its high adsorption capacity. Activated carbons can be produced from many materials such as coals, woods, or agricultural waste. Some of them were prepared by specific activation methods to improve the surface area. Some researchers also used modified activated carbon by adding specific additive to improve its performance in attracting formaldehyde molecules. Proposed modification methods on activation and additive impregnated carbon are thus discussed in this paper for future development and improvement of formaldehyde adsorption on activated carbon. Specifically, a waste agricultural product is chosen for activated carbon raw material because it is renewable and gives an added value to the materials. The study indicates that the performance of the adsorption of formaldehyde might be improved by using modified activated carbon. Bamboo seems to be the most appropriate raw materials to produce activated carbon combined with applying chemical activation method and addition of metal oxidative catalysts such as Cu or Ag in nano size particles. Bamboo activated carbon can be developed in addition to the capture of formaldehyde as well as the storage of adsorptive hydrogen gas that supports renewable energy. Keywords: adsorption; bamboo; formaldehyde; modified activated carbon; nano size particles


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.  


Energies ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2237
Author(s):  
Sara Stelitano ◽  
Giuseppe Conte ◽  
Alfonso Policicchio ◽  
Alfredo Aloise ◽  
Giovanni Desiderio ◽  
...  

Pinecones, a common biomass waste, has an interesting composition in terms of cellulose and lignine content that makes them excellent precursors in various activated carbon production processes. The synthesized, nanostructured, activated carbon materials show textural properties, a high specific surface area, and a large volume of micropores, which are all features that make them suitable for various applications ranging from the purification of water to energy storage. Amongst them, a very interesting application is hydrogen storage. For this purpose, activated carbon from pinecones were prepared using chemical activation with different KOH/precursor ratios, and their hydrogen adsorption capacity was evaluated at liquid nitrogen temperatures (77 K) at pressures of up to 80 bar using a Sievert’s type volumetric apparatus. Regarding the comprehensive characterization of the samples’ textural properties, the measurement of the surface area was carried out using the Brunauer–Emmett–Teller method, the chemical composition was investigated using wavelength-dispersive spectrometry, and the topography and long-range order was estimated using scanning electron microscopy and X-ray diffraction, respectively. The hydrogen adsorption properties of the activated carbon samples were measured and then fitted using the Langmuir/ Töth isotherm model to estimate the adsorption capacity at higher pressures. The results showed that chemical activation induced the formation of an optimal pore size distribution for hydrogen adsorption centered at about 0.5 nm and the proportion of micropore volume was higher than 50%, which resulted in an adsorption capacity of 5.5 wt% at 77 K and 80 bar; this was an increase of as much as 150% relative to the one predicted by the Chahine rule.


Processes ◽  
2019 ◽  
Vol 7 (11) ◽  
pp. 855 ◽  
Author(s):  
Azry Borhan ◽  
Suzana Yusup ◽  
Jun Wei Lim ◽  
Pau Loke Show

Global warming due to the emission of carbon dioxide (CO2) has become a serious problem in recent times. Although diverse methods have been offered, adsorption using activated carbon (AC) from agriculture waste is regarded to be the most applicable one due to numerous advantages. In this paper, the preparation of AC from rubber-seed shell (RSS), an agriculture residue through chemical activation using potassium hydroxide (KOH), was investigated. The prepared AC was characterized by nitrogen adsorption–desorption isotherms measured in Micrometrices ASAP 2020 and FESEM. The optimal activation conditions were found at an impregnation ratio of 1:2 and carbonized at a temperature of 700 °C for 120 min. Sample A6 is found to yield the largest surface area of 1129.68 m2/g with a mesoporous pore diameter of 3.46 nm, respectively. Using the static volumetric technique evaluated at 25 °C and 1.25 bar, the maximum CO2 adsorption capacity is 43.509 cm3/g. The experimental data were analyzed using several isotherm and kinetic models. Owing to the closeness of regression coefficient (R2) to unity, the Freundlich isotherm and pseudo-second kinetic model provide the best fit to the experimental data suggesting that the RSS AC prepared is an attractive source for CO2 adsorption applications.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Geni Juma ◽  
Revocatus Machunda ◽  
Tatiana Pogrebnaya

In this study, sweet potato leaf activated carbon (SpLAC) was prepared by the chemical activation method using KOH and applied as an adsorbent for H2S removal from biogas. The study focused on the understanding of the effect of carbonization temperature (Tc), varying KOH : C activation ratio, flow rate (FR) of biogas, and mass of SpLAC on sample adsorption capacity. The BET analysis was performed for both fresh and spent activated carbons as well as for carbonized samples, which were not activated; also, the activated carbon was characterized by XRF and CHNS techniques. The results showed that removal efficiency (RE) of the SpLAC increased with increase carbonization temperature from 600 to 800°C and the mass of sorbent from 0.4 g to 1.0 g. The optimal test conditions were determined: 1.0 g of sorbent with a KOH : C ratio of 1 : 1, Tc=800°C, and FR=0.02 m3/h which resulted in a sorption capacity of about 3.7 g S/100 g of the SpLAC. Our findings corroborated that H2S removal was contributed not only by the adsorption process with the pore available but also by the presence of iron in the sample that reacted with H2S. Therefore, upon successful H2S sorption, SpLAC is suggested as a viable adsorbent for H2S removal from biogas.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
N. Mojoudi ◽  
N. Mirghaffari ◽  
M. Soleimani ◽  
H. Shariatmadari ◽  
C. Belver ◽  
...  

AbstractThe purpose of this study was the preparation, characterization and application of high-performance activated carbons (ACs) derived from oily sludge through chemical activation by KOH. The produced ACs were characterized using iodine number, N2 adsorption-desorption, Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The activated carbon prepared under optimum conditions showed a predominantly microporous structure with a BET surface area of 2263 m2 g−1, a total pore volume of 1.37 cm3 g−1 and a micro pore volume of 1.004 cm3 g−1. The kinetics and equilibrium adsorption data of phenol fitted well to the pseudo second order model (R2 = 0.99) and Freundlich isotherm (R2 = 0.99), respectively. The maximum adsorption capacity based on the Langmuir model (434 mg g−1) with a relatively fast adsorption rate (equilibrium time of 30 min) was achieved under an optimum pH value of 6.0. Thermodynamic parameters were negative and showed that adsorption of phenol onto the activated carbon was feasible, spontaneous and exothermic. Desorption of phenol from the adsorbent using 0.1 M NaOH was about 87.8% in the first adsorption/desorption cycle and did not decrease significantly after three cycles. Overall, the synthesized activated carbon from oily sludge could be a promising adsorbent for the removal of phenol from polluted water.


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