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Optimization and performance prediction of carbon dioxide adsorption on chitosan/activated carbon/epichlorohydrin composite materials using Box–Behnken design and artificial neural network approaches
(2025-06-01)
Loryuenyong, Vorrada
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Nakhlo, Worranuch
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Srikaenkaew, Praifha
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Yaidee, Panpassa
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Eiad-Ua, Apiluck
Spent coffee grounds (SCGs) can be used as biomass to synthesize activated carbon (AC) through physical carbonization and chemical activation. Epichlorohydrin (EP) was used to create the chitosan (CS) and AC biopolymer composites via emulsion crosslinking. The main goal of this research is to boost the efficiency of CS/AC/EP composite materials for carbon dioxide (CO<inf>2</inf>) capture by adsorption. The impact of CS content, AC concentration, and EP quantity on CO<inf>2</inf> removal was studied applying the Box–Behnken design (BBD)-based response surface methodology (RSM) and artificial neural network (ANN)-based artificial intelligence (AI) models. The conditions for the adsorption process were optimized to forecast the maximum CO<inf>2</inf> adsorption utilizing BBD and ANN approaches. Optimal process parameters of 15.11 g CS content, 38.95 %w/w AC concentration, and 7.16 g EP quantity resulted in a CO<inf>2</inf> adsorbed of approximately 7.62 cm3/g. The coefficient of determination (R2) for the BBD model was 0.9995, while the correlation coefficient (R) for the ANN model was 0.9992. The CO<inf>2</inf> adsorption efficiency of adsorbents is enhanced by increasing the amounts of AC and EP. This study provides a technique for predicting and improving CO<inf>2</inf> capture through the development of porous polymer composite beads (CBs) with a high CO<inf>2</inf> adsorption capacity.
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Biodiesel produced from transesterification of palm oil using NaOH-treated activated carbon and pyrolytic char of used tires as catalysts
(2025-03-01)
Chana, Khulanuttha
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Chen, Bing Hung
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Na-Ranong, Duangkamol
Biodiesel produced from catalyzed transesterification of palm oil with methanol using NaOH-treated carbonaceous catalysts was studied and reported. Particularly, effect of the carbonaceous support, i.e. activated carbon (AC) and pyrolytic char of end-of-life used tire (TPC), on the yield of biodiesel was investigated. The resultant yield of biodiesel near 98.5 % could be attained from transesterification reactions conducted with a catalyst loading at 5 wt% of palm oil initially used, under a molar ratio of methanol/oil at 21/1, at 65°C and 180 min for reaction temperature and time. The kinetics of the transesterification reaction could be fitted satisfactorily with the pseudo first-order model. The Arrhenius behavior was observed from the temperature-dependent rate constants, leading to an activation energy at 111.2 kJ/mol if AC-supporting catalyst was used. Both AC and TPC-supporting catalysts could produce biodiesel with a yield greater than 90 % even after the fourth cycles of catalyzed transesterification reactions. Notably, the feasibility in the upcycling of TPC as catalyst support was demonstrated in this work.
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Self-activation of carbons derived from bio-waste cabbage for a green supercapacitor based on seawater electrolyte
(2024-12-01)
Phakkhawan, Authit
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Sakulkalavek, Aparporn
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Chanlek, Narong
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Nijpanich, Supinya
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Ngernyen, Yuvarat
Carbonized carbons (CC) derived from cabbage were self-activated via a carbonization process at 500–900 °C in Ar. CC synthesized at 800 °C (CC-800), containing KCl, CaCO<inf>3</inf>, Ca(ClO)<inf>2</inf>, K<inf>2</inf>SO<inf>4</inf>, and Ca<inf>5</inf>(PO<inf>4</inf>)<inf>3</inf>(OH), has the highest specific surface area (S<inf>BET</inf>, 130.04 m2 g−1), a high specific capacitance (64.06 F g−1), and an excellent rate capability (65.12 %). After washing the CC-800 powder in either deionized (DI) water (AC-DI) or hydrochloric acid (HCl) followed by DI water (AC-HCl-DI), S<inf>BET</inf> values increased to 919.22 and 1146.51 m2 g−1, respectively. KCl, Ca(ClO)<inf>2</inf>, and K<inf>2</inf>SO<inf>4</inf> are removed from the AC-DI, whereas all compounds are washed from the AC-HCl-DI. Removing these compounds enlarges S<inf>BET</inf> values, specific capacitance (114.47 F g−1 at 0.5 A g−1), and rate capability (68.95 %). A high capacitance retention of 97.56 % after 20,000 cycles was achieved from the AC-HCl-DI electrode with 6 M KOH. 0.6 M NaCl and seawater were applied as green electrolytes with the AC-HCl-DI electrode, resulting in the promising specific capacitance of 116.89 and 102.21 F g−1 at 0.5 A g−1, respectively. Symmetric AC-HCl-DI/seawater/AC-HCl-DI cell gives a high energy density of 2.32 Wh kg−1 at a large power density of 0.25 kW kg−1. The four serial AC-HCl-DI/seawater/AC-HCl-DI coin cells could light an LED over 60 s.
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Synergy of functionalized activated carbon and ZnO nanoparticles for enhancing photocatalytic degradation of methylene blue and carbaryl
(2024-10-01)
Rungsawang, Tipawan
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Krobthong, Sucheewan
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Paengpan, Krisanachai
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Kaewtrakulchai, Napat
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Manatura, Kanit
This study proposes preparing ZnO and ZnO/activated carbon (AC) for photocatalytic applications. ZnO and AC were synthesized using precipitation and carbonization processes, respectively. Particle sizes of ZnO and ZnO/AC were estimated at 121–135 nm. The crystalline structure analysis confirmed the presence of hexagonal wurtzite structures in ZnO. Microcrystalline graphite and amorphous carbon structures were observed in AC. The combination of these characteristics was observed in ZnO/AC. ZnO/AC exhibited an increase in surface area from 25.36 to 29.86 m2/g and a decrease in pore diameter from 5.66 to 4.31 nm. The chemical states of ZnO and AC remained unchanged. Therefore, the nanocompound structure of ZnO/AC can be inferred. The ZnO/AC nanocompounds were then employed to degrade methylene blue (MB) dye and carbaryl (CBR) insecticide, demonstrating excellent photocatalytic performance compared to pure ZnO. The apparent degradation rate constant reached an average value of 3.49 × 10−3 and 16.25 × 10−3 min−1 for MB and CBR, respectively. AC functions as carrier collectors in the ZnO/AC nanocompound structures due to the suitable energy band level for facilitating electron and hole transfers. This results in recombination suppression and prolonged lifetime, thus enhancing photocatalytic activity. The finding suggests the potential use of ZnO/AC nanocompounds to degrade agricultural chemicals in contaminated natural water under sunlight.
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Rubber Wood Sawdust Waste Converted to Activated Carbon for Heavy Metal Removal from Wastewater
(2023-01-01)
Kengchuwong, Metta
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Ketwong, Chatyapha
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Nuasri, Chompoo
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Wanich, Suchana
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Trisupakitti, Somsuk
In this study, we characterized activated carbon prepared from rubber wood sawdust waste and determined optimum conditions for removing copper ions from synthetic wastewater. Rubber wood sawdust was calcined at 600°C for 30 min and then activated with commercial vinegar (5%v/v acetic acid) or 5% lime juice for 24 hr. Three characteristics of the activated carbon were evaluated: (i) to study the ability to remove copper ions versus exposure time, pH and the amount of adsorbent, (ii) adsorption isotherms and (iii) adsorption kinetics. A Langmuir isotherm indicated that the activated carbon adsorbed a monolayer of Cu(II) ions, K<inf>L</inf> = 7.91 mg/L with a capacity to adsorb 0.37 mg Cu(II)/g. The optimum conditions for usage was found at 20 g/L activated carbon in wastewater, pH 5 and 60 min adsorption time. Adsorption kinetics were consistent with a pseudo-second order reaction. The results of the study suggest that converting rubber wood sawdust waste to activated carbon allows it to become useful to remove heavy metal pollutants from wastewater.
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PREPARATION OF ACTIVATED CARBON FROM TIRE DERIVED PYROLYTIC CHAR FOR ADSORPTION OF TETRACYCLINE HYDROCHLORIDE
(2022-12-01)
Chana, Khulanuttha
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Soisuwan, Sasit
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Sinpichai, Sarawut
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Chen, Bing Hung
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Na-Ranong, Duangkamol
Effects of activation variables on performance of the obtained activated carbon (AC) were investigated for removal of tetracycline hydrochloride (TCH). Pyrolytic char derived from waste tire was chemically activated via two-step of KOH impregnation following by thermal treatment. According to regression analysis and fitting with second-degree polynomial equation, empirical models were developed to correlate performance of AC in TCH adsorption (percentage removal and adsorption capacity at equilibrium) with three activation variables: impregnation ratio (IR), activation temperature (T) and holding time of thermal treatment (t). The analysis of variance indicated that only T, T2 and IR2 were significant to the prediction of both percentage removal and adsorption capacity. According to the developed models, it is suggested that the pyrolytic char should be activated at IR = 6, T = 750 °C and t = 2 h to obtain the highest efficiency of TCH removal in the tested range of activation condition.
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Electrochemical mechanisms of activated carbon, α-MnO2 and composited activated carbon-α-MnO2 films in supercapacitor applications
(2021-12-30)
Tagsin, Patin
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Suksangrat, Pitphichaya
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Klangtakai, Pawinee
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Srepusharawoot, Pornjuk
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Ruttanapun, Chesta
Pure α-MnO<inf>2</inf> and activated carbon-MnO<inf>2</inf> (AC-MnO<inf>2</inf>) films coated on Ni foam by electrophoretic deposition were applied as a supercapacitor electrode. The specific capacitance of AC-MnO<inf>2</inf> films (155.03 F g−1) surpasses those of the pure AC (110.62 F g−1) and pure MnO<inf>2</inf> film in the 1 M NaOH electrolyte. EDX and XPS detect an increase in the Na content and the reduction of Mn4+ to Mn3+ on the discharged MnO<inf>2</inf> electrode (at 0.0 V), whereas a decrease in the Na content and the oxidation of Mn3+ to Mn4+ were obtained on the charged MnO<inf>2</inf> electrode (at 0.45 V). Computational simulation of the Na inserted α-MnO<inf>2</inf> structure displays the connection of Na to O atoms and the increasing electron density on Mn atoms. EDX of the charged AC-MnO<inf>2</inf> (at −1.0 V) film detects a rise in the Na and a fall in the O contents, but the discharged AC-MnO<inf>2</inf> film (at 0.0 V) shows a decrease in Na and increase in O contents. The AC-MnO<inf>2</inf> film could retain 82.29% of the initial specific capacity after 10,000 cycles. Four series-supercapacitor coin cell assembled from the AC-MnO<inf>2</inf> anode and MnO<inf>2</inf> cathode delivers a power density of 2.79 kW kg−1 and an energy density of 168.8 Wh kg−1.
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Effect of pd precursor salts on the chemical state, particle size, and performance of activated carbon-supported pd catalysts for the selective hydrogenation of palm biodiesel
(2021-02-01)
Udomsap, Parncheewa
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Eiad-Ua, Apiluck
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Chen, Shih Yuan
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Mochizuki, Takehisa
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Chollacoop, Nuwong
To improve the oxidative stability of biodiesel fuel (BDF), the polyunsaturated fatty acid methyl esters (poly-FAME) presented in commercial palm oil-derived biodiesel fuel (palm-BDF) were selectively hydrogenated to monounsaturated fatty acid methyl esters (mono-FAME) under a mild condition (80 °C, 0.5 MPa) using activated carbon (AC)-supported Pd catalysts with a Pd loading of 1 wt.%. The partially hydrotreated palm-BDF (denoted as H-FAME) which has low poly-FAME components is a new type of BDF with enhanced quality for use in high blends. In this study, we reported that the chemical states and particle sizes of Pd in the prepared Pd/AC catalysts were significantly influenced by the Pd precursors, Pd(NO3)2 and Pd(NH3)4Cl2, and thus varied their hydrogenation activity and product selectivity. The 1%Pd/AC (nit) catalyst, prepared using Pd(NO3)2, presented high performance for selective hydrogenation of poly-FAME into mono-FAME with high oxidation stability, owning to its large Pd particles (8.4 nm). Conversely, the 1%Pd/AC (amc) cata-lyst, prepared using Pd(NH3)4Cl2, contained small Pd particles (2.7 nm) with a little Cl residues, which could be completely removed by washing with an aqueous solution of 0.1 M NH4OH. The small Pd particles gave increased selectivity toward unwanted-FAME components, particularly the saturated fatty acid methyl esters during the hydrogenation of poly-FAME. This selectivity is un-profitable for improving the biodiesel quality.
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Preparation of activated carbon from durian rind with difference activations and its optimization
(2021-01-01)
Sriprom, Pongsert
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Krusong, Warawut
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Assawasaengrat, Pornsawan
Durian rind wastes are an important raw material for activated carbon production due to their renewable sources and low-cost materials. The efficiency of increasing surface area and the quantity of oxygen groups on the surface of activated carbon were studied for the preparation of activated carbon. The preparation of activated carbon has been studied with the different methods as follows: activation by acid, activation by base, hydrothermal and activation by acid, and hydrothermal and activation by base. The results showed that hydrothermal and activation by acid had high iodine number which was chosen to determine the optimum condition for activated carbon preparation. The optimum condition for preparation of durian rind activated carbon was studied by Box-Behnken design. Solid/water ratio, solid/acid ratio and temperature were chosen as the important parameters for achieving the optimum reaction condition. The reaction products were analyzed by iodine number. Based on the results, the optimum condition for preparation of durian rind activated carbon was predicted using RSM. The maximum iodine number of 626.47 mg/g was expected at the optimum condition: solid/ water ratio (1:175, g/mL), solid/acid ratio (1:23, g/mL) and temperature (500°C). The preparation of durian rind activated carbon at the optimal condition was carried; the percentages of iodine number achieved (666.73 ± 6 mg/g) were close to the maximum predicted value (666.73 mg/g), thus verifying the model. At the optimum condition, the functional group on surface of durian rind activated carbon was characterized by FT-IR. The result showed that the oxygen content on surface was increased in the form of carbonyl and sulfonyl group.
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Preparation of activated carbon via acidic dehydration of durian husk for supercapacitor applications
(2020-08-01)
Ukkakimapan, Pundita
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Sattayarut, Vichuda
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Wanchaem, Thanthamrong
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Yordsri, Visittapong
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Phonyiem, Mayuree
In this study, the preparation of activated carbons (ACs) via acidic dehydration of durian husk (DH) for supercapacitor application was investigated. The DH was dehydrated using sulfuric acid and subsequently activated by using sodium hydroxide as chemical reagent at 720 °C to obtain activated carbon (hereinafter referred to as DA). Surpassing the commercial ACs and the ACs derived from the conventional carbonization and activation (hereinafter referred to as CA), the DA exhibited superior properties in high surface area (2578 m2/g) and total pore volume (1.27 cm3/g). Moreover, besides carbon and oxygen, the DA contained sulfur and nitrogen in the carbon network. The DA can act as a suitable material for supercapacitor electrode with the specific gravimetric and volumetric capacitances of 145 F/g and 70 F/cm3 in an organic electrolyte. The device also showed a promising performance with an energy density of 32 Wh/kg and a power density of 316 W/kg. These results demonstrate that the preparation of ACs via acidic dehydration of DH offers the advantages in terms of simplicity, low cost, and short-time processing to achieve heteroatom self-doped ACs with a high surface area for high-performance supercapacitors.

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