• Applied Chemistry for Engineering
• /
• v.24 no.4
• /
• pp.370-374
• /
• 2013

The effects of zinc chloride addition on pore development of porous carbon nanofibers prepared by polyacrylonitrile (PAN)/ N,N'-dimethylformamide (DMF) (10 wt%) electrospinning were investigated. The change of morphological and structural modification by zinc chloride activation was investigated by a scanning electron microscopy (SEM) analysis. $N_2$ adsorption isotherm characteristics at 77 K were confirmed by Brunauer-Emmett-Teller (BET) and Horvath-Kawazoe (H-K) equations, and the curves showed the Type I mode in the International Union of Pore and Applied Chemistry (IUPAC) classification, indicating that lots of micropores exist in the sample. In addition, specific surface areas and total pore volumes of porous carbons prepared by the zinc chloride activation were determined as 600~980 $m^2/g$ and 0.24~0.40 $cm^3/g$, respectively. As experimental results, many holes or demolished structures were found on the fiber surfaces after the zinc chloride activation as confirmed by a SEM analysis. It was also observed that various pore sizes were found to be depended on the adding content of zinc chloride in PAN/DMF solution in this system.

• Journal of the Korean Wood Science and Technology
• /
• v.52 no.2
• /
• pp.118-133
• /
• 2024

The sapwood portion of fast-growing teak is mostly ignored due to its inferior quality. One of the possibilities for utilizing sapwood waste is to convert it into activated carbon that has good adsorption capabilities. The raw materials used in this research were sapwood of 14-year-old fast-growing teak sapwood (FTS) waste, which was taken from three trees from community forests in Wonosari, Gunungkidul, Yogyakarta Special Region. FTS waste was taken from the bottom of the tree up to a height of 1.3 m. The activation process is conducted with an activation temperature of 750℃, 850℃, and 950℃. The heating duration consists of three variations: 30 min, 60 min, and 90 min. The quality evaluation parameters of activated carbon include yield, moisture content, volatile matter content, ash content, fixed carbon content, adsorption capacity of benzene, adsorption capacity of methylene blue, and adsorption capacity of iodine. The results showed that the activated carbon produced had the following quality parameters: yield of 75.61%; moisture content of 1.27%; volatile matter content of 9.98%; ash content of 5.43%; fixed carbon content of 84.58%; benzene absorption capacity of 8.58%; methylene blue absorption capacity of 87.73 mg/g; and iodine adsorption capacity of 948.19 mg/g. It can be concluded that activated carbon from FTS waste has good iodine adsorption, which fulfilled the SNI 06-3730-1995 quality standard. Due to the iodine adsorption ability of FTS waste activated carbon, the conversion of FTS waste to activated carbon is categorized as a potential method to increase the value of this material.

• Environmental Engineering Research
• /
• v.22 no.4
• /
• pp.384-392
• /
• 2017

Mango shell (MS) and mango shell activated carbon (MSAC) was used to adsorb crude oil from water at various experimental conditions. The MSAC was prepared by carbonization at $450^{\circ}C$ and chemical activation using strong $H_3PO_4$ acid. The adsorbents were characterized with Fourier Transform Infrared spectroscopy. Investigations carried out included the effects of parametric variations of different adsorbate dose, adsorbent dose, time, temperature, pH and mixing speed on the adsorption of crude oil. The equilibrium isotherm for the adsorption process was determined using Langmuir, Freundlich, Temkin and Dubinin Radushkevich isotherm models. Temkin isotherm was found to fit the equilibrium data reasonably well than others. The result demonstrated that MSAC was more effective for crude oil adsorption than raw mango shell. Optimum conditions were also presented. The enhanced effect from activation was justified statistically using Analysis of Variance and Bonferroni-Holm Posthoc significance test. The pseudo first order kinetics gave a better fit for crude oil adsorption with both MS and MSAC.

• Elastomers and Composites
• /
• v.35 no.2
• /
• pp.122-131
• /
• 2000

In this work, the effect of chemical surface treatments on morphology of carbon blacks was investigated in terms of cure behavior and tearing energy ($G_T$) of carbon blacks/rubber composites. As experimental results, the polar or nonpolar chemical treatment led to a significant physical change of carbon black morphology. The cure activation energies (Ea) and frequency factor (A) obtained from Kissinger equation decreased with improving the dispersion of carbon flacks, resulting in high reactivity. However, a significant advantage of carbon black/rubber composites is gained by carbon blacks treated in basic (BCB) or nonpolar (NCB) chemical solution, resulting in increasing the tearing energy. These results could be explained by changes of dispersion, agglomerate, surface functional group, void volume, and cross-linking density of carbon black/rubber composites.

• Journal of the Korean Wood Science and Technology
• /
• v.52 no.5
• /
• pp.488-503
• /
• 2024

Shoot waste refers to the parts of trees that are not yet optimally utilized. In this study, we aimed to utilize shoot waste of fast-growing teak (FGT) extracted from the community forest in Wonosari, Gunungkidul, Yogyakarta Special Region, Indonesia by converting it into charcoal, followed by further conversion into activated carbon. This study was conducted with two treatment factors of the activation process, including thermal treatment (750℃, 850℃, and 950℃) and heating period (30, 60, and 90 min), to determine the best condition for the activation process. Our results indicated a significantly effect of the interaction between thermal treatment and heating period on the moisture content, volatile matter content, ash content, fixed carbon content, and adsorption properties of the produced activated carbon. The highest iodine adsorption capacity of activated carbon is 1,102.57 mg/g, which was produced by thermal treatment at 750℃ and heating period of 30 min. This result fulfilled the Indonesian National Standard (SNI 06-3730-1995 quality standard). Furthermore, the quality parameters of the produced activated carbon include: moisture content of 6.13%; volatile matter content of 17.27%; ash content 5.24%; fixed carbon content of 77.49%; benzene removal efficiency of 8.43%; and methylene blue adsorption capacity of 69.66 mg/g. Based on this study, we concluded that shoot waste of FGT could be classified as a prospective material for developing activated carbon for industrial application.

• Applied Chemistry for Engineering
• /
• v.34 no.6
• /
• pp.576-583
• /
• 2023

This study investigated the possibility of new adsorbent materials made from pig bone-based biomass. To this end, the properties of pig bone-based activated carbon (PAC) prepared from animal biomass were investigated, and its carbon dioxide adsorption performance was examined. KOH was used as the activation agent, and the specific surface area increased with increasing activation temperature, and the adsorption efficiency of carbon dioxide also increased. The sample activated at 800 ℃ exhibited the largest specific surface area of 1208.7 m²/g and the highest CO₂ adsorption efficiency of 3.33 mmol/g at 273 K, 1 bar. However, the specific surface area and the CO₂ adsorption efficiency decreased at activation temperatures above 900 ℃ due to crystallinity changes and overactivation. On the other hand, when the selectivity was calculated using the ideal adsorption solution theory, PAC-900 samples at 273 K and below 0.8 bar showed the best selectivity. These results suggest that the high selectivity of carbon dioxide/nitrogen adsorption at 273 K is due to the carbon dioxide adsorption capacity of hydroxyapatite formed by the decomposition of carbonate when pig bone is activated at 900 ℃ and its crystallinity.

• Journal of the Korean Society of Safety
• /
• v.31 no.1
• /
• pp.66-73
• /
• 2016

Lyocell fibers were used as a precursor in order to improve yield and strength of cellulose-based precursor while manufacturing activated carbon fiber(ACF). Lyocell fibers as a precursor for the preparation of ACF were surface-modified by reaction with 3-aminopropyltriethoxysilane(APTES) and pre-treated with KOH and H3PO4. Using aforementioned precursor, ACFs were prepared by a series of stabilization, carbonization and activation process at high temperatures. On each process, FT-IR, TGA, UTM and SEM were used to observe fibers' physical properties including structure and porous surfaces. FT-IR results proved that surface modification was achieved during stabilization, carbonization and activation process. TGA results during carbonization process found that surface modified fibers with APTES 0.02 mol(A2) showed higher thermostability, and extended pre-treatment increased yield. Especially, yield was found to have an increase of 10~20 wt% with surface modification during activation process. UTM results showed that tensile strength has the same order of concentration of APTES after surface modification, however, was found to show lower tensile strength than lyocell fibers after stabilization process. SEM results revealed that more homogeneous porosity control could be proceed after modifying the surface for the effective removal of hazardous substances.

• Applied Chemistry for Engineering
• /
• v.17 no.5
• /
• pp.532-538
• /
• 2006

The carbonization and activation conditions for the PAN-based ACF of various grade were investigated to obtain the optimun activation condition with high surface area. And the surface properties and the absorption performance of toxic gas for terror were examined toward the PAN-ACF with the highest surface area. In the test results the surface area increased with increase of the activation temperature, but decreased with increase of the carbonization temperature. After carbonization condition ($900^{\circ}C$-15min) and activation condition ($900^{\circ}C$-30 min), we got the ACF with the highest surface area of $1204m^2/g$. In the absorption test of iodine and toxic gas for terror, this ACF showed more excellent absorption performance than the existing carbon-based adsorbent. Also, in order to give the function characteristic for a selective absorption, the stable nanoparticles of the Ag, Pt, Cu, Pd were prepared and impregnated on the PAN-based ACF in replacement of the existing method supporting metal catalysis. And were analyzed the surface characteristics and the $SO_{2}$ adsorption characteristics. In the $SO_{2}$ absorption performance test of the PAN-ACF with the impregnated nanoparticles, it wasn't change breakthrough time of Ag, Pt, Cu nanoparticle supported the PAN-ACF comparing with breakthrough time (326 sec) of the non supported PAN-ACF but Pd nanoparticle supported the PAN-ACF achieved excellent $SO_{2}$ absorption performance which has break-through time 925 sec.

• Carbon letters
• /
• v.22
• /
• pp.81-88
• /
• 2017

In the present study, biomass-based lignin was extracted from industrial waste black liquor and the extracted lignin was characterized by means of attenuated total reflectance-Fourier transform infrared spectroscopy and $^1H-nuclear$ magnetic resonance spectroscopy. The extracted lignin was carbonized at different temperatures and then activated with steam at $850^{\circ}C$. The extracted lignin in powder state was transformed into a bulky carbonized lignin due to possible fusion between the lignin particles occurring upon carbonization. The carbonized and then pulverized lignin exhibits brittle surfaces, the increased thermal stability, and the carbon assay with increasing the carbonization temperature. The scanning electron microscopic images and the Brunauer-Emmett-Teller result indicate that the steam-activated carbon has the specific surface area of $1718m^2/g$, which is markedly greater than the carbonized lignin. This study reveals that biomass-based activated carbon with highly porous structure can be produced from costless black liquor via steam-activation process.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.25 no.3
• /
• pp.63-71
• /
• 2017

In this study, washing parameters such as washing time, agitation velocity, and cycles were optimized for high surface area of the activated carbon (AC) by KOH activation. Even though AC with high surface area showed at higher washing efficiency, over 90% on washing efficiency was regulated by the intra-particle diffusion due to high tortuosity of the pore structures on AC. In addition, we can obtain $K_2CO_3$ through the evaporation from the wastewater and use it for chemical activation of AC. The AC with $K_2CO_3$ activation has specific surface area values of $2,219m^2/g$ equally that of KOH activation. Considering that $K_2CO_3$ is an effective alternative as a KOH, our results demonstrated that the process by recycling wastewater on AC production could be applicable for near-zero wastes.