Optimum Carbonization Temperature Research Articles

Coin‐Shaped Carbon Prepared with Cerbera manghas Fibers via Multistage Carbonization and Activation for High‐Performance Symmetrical Supercapacitors

AbstractSupercapacitor energy storage devices and activated carbon (AC) manufacturing materials for producing high‐performance supercapacitors have received extensive attention from researchers. Biomass‐based AC has been extensively studied due to its environmental friendliness, abundant availability, porous structure, and high specific surface area. This work focuses on developing biomass‐based carbon electrodes derived from Cerbera manghas fiber (CMF) with variations in carbonization temperature to obtain optimum supercapacitor cell performance. The prepared CMF AC was characterized using energy dispersive X‐ray, Fourier transform infrared, X‐ray diffraction, scanning electron microscope, and nitrogen isothermal adsorption–desorption. CMF AC with the optimum carbonization temperature (CMF‐600) produced a fibrous structure with a lot of mesoporous so that the specific surface area and specific capacitance were high, namely, 721.495 m2 g−1 and 221 F g−1 at scan rate 1 mV s−1, respectively. The results of this study indicate that selecting the optimum temperature can enhance the performance of supercapacitor cells and make AC based on CMF biomass potential for cheap and efficient energy storage applications.

Biomass valorization of Mangifera Indica into hierarchical carbon materials with self-doping oxygen assisted carbonization for supercapacitor applications

ABSTRACT The exploration of biocompatible energy storage media for future generations has been continuously carried out. This includes the investigations of electrode materials that are renewable, environmentally friendly, cost-effective, and rich in heteroatoms. The electrode materials undergo carbonization as a promising thermochemical process to create an active material with a porous structure of well-defined and controlled geometry. The main objective of this study is to thoroughly examine the conversion process of electrode materials derived from Mangifera Indica Seed Shells (MIS) using carbonization and activation methods for supercapacitor applications. Pyrolysis at various temperatures was carried out to determine the definitive influence of carbonization temperature on the capacitive performance of MIS active materials. The optimum carbonization temperature of 600°C significantly enhances mesoporosity, which is positively correlated to the specific surface area, hierarchical structure, and the presence of self-doping oxygen, leading to a substantial increase in capacitive behavior. In the experiment, the MIS samples were used as electrodes for supercapacitor cells, and they were found to exhibit a specific capacitance of 255 Fg−1. The goal of this study is to offer a sustainable solution by using biomass as an active material for high-performance supercapacitor cells that can be utilized in energy storage applications.

Insights into microplastics (MPs) removal using aquatic plant-derived biochar from Taihu Lake at varying carbonization temperatures

Microplastics (MPs), recognized as significant emerging contaminants, are prevalent in both terrestrial and aquatic ecosystems. This study investigates the potential of biochar derived from Polygonum amphibium L. (PAL) sourced from Taihu Lake and processed through a low-temperature carbonization method, for in the removal of MPs. This approach addresses the escalating presence of MPs in aqueous environment, especially during the COVID-19 pandemic, simultaneously tackles the issue of waste biomass contributing to eutrophication. The study focused on the impact of carbonization temperatures (450℃-550℃) on physicochemical properties of biochar. Additionally, the effect of contact time, initial concentration of MPs, and environmental factors at various carbonization temperatures were also examined. The results reveal that the biochar yield and adsorption performance of biochar are significantly influenced by carbonization temperature. The adsorption capacity of biochar for MPs removal increases with the carbonization temperature up to 500 ℃, attributed to enhanced diffusion, surface adsorption, interactions, and cation-π electron interactions between the biochar and MPs. However, at a pyrolysis temperature of 550 ℃, the increase in adsorption capacity of biochar-550 is marginal due to increased competitive binging and destabilization of biochar under basic conditions. Overall, the optimum carbonization temperature is identified as 500 ℃, yielding a char rate is 32.23% and an adsorption capacity for MPs of 80.3 mg/g, thereby offering a promising solution for MP removal and water eutrophication management.

Fabrication and Characterization of Activated Carbon from ‘Aking rice’ Waste

Rice as a staple food for most Indonesian people contributes a high amount of food waste. Indonesian people generally process cooked rice waste into ‘Aking rice’. ‘Aking rice’ is a result from the drying of cooked rice with the sun. ‘Aking rice’ is generally used as animal feed, but on the other hand, aking rice has the potential to be used as a source of activated carbon because it contains high carbon. We learn the optimum carbonization temperature for making activated carbon from aking rice by conducting several characterization tests on activated charcoal from each carbonization temperature. The fabrication method of activated carbon in this research occurs in two steps, carbonization first followed by chemical activation using HCl. The carbonization temperature variations are 300°C, 400°C, and 500°C. The optimum carbonization temperature is 500°C because all results comply with requirement. Activated carbon from carbonization temperature at 500°C has water content of 0,96%, ash content of 0,98%, volatile matter content of 19,30%, and fixed carbon content 79,72%. Variation of carbonization temperature does not give significant effect for ash content and water content, but give significant effect for volatile matter content and fixed carbon content.

Carbonized Nickel‐Loaded Spent Coffee Grounds Modified BiOCl Photocatalysts for Enhanced Degradation of Ofloxacin

AbstractWater pollution has posed a serious threat to the environment and human health. There is an urgent need to develop highly efficient and application‐convenient photocatalytic materials. To overcome this critical problem, the carbonized nickel‐loaded spent coffee grounds modified BiOCl (CNSCG‐BOC‐8) photocatalyst is prepared by using facile calcination and hydrolysis method. The optimum substrate carbonization temperature, the amount of substrate, and the loading amount of nickel ion are discussed. Further, the photocatalytic performance of the catalyst is tested using Ofloxacin (OFX) as target pollutant under ultraviolet and visible light (UV–vis light). The as‐obtained photocatalysts show the degradation efficiency of OFX in the prepared composite reaches 87% within 40 min under ultraviolet and visible light. Moreover, the results show that CNSCG‐BOC‐8 has better photoelectricity, excellent cycle stability, and is environment‐friendly. Therefore, this paper provides an important reference for the rational development and use of Ni‐loaded biomass‐derived carbon as the substrate to modify bismuth‐based photocatalyst for environmental remediation.

ARANG AKTIF SERAT SABUT KELAPA DAN APLIKASINYA SEBAGAI ADSORBEN ION KROMIUM(III) DARI LARUTAN AIR

The coconut husk contains high cellulose, so it can be processed as a basic materials to make activated charcoal. The purpose of the study was to make activated charcoal from coconut husk fiber with hydrochloric acid activator and to determine the effect of changing coconut husk fiber into charcoal, as well as activation of the adsorption power of Cr(III) metal ions from solution. The research started by separating the coconut husk fiber, carbonization at various temperatures. The resulting charcoal was characterized according to SNI 06-3730-1995. The best quality charcoal was activated with HCl, then coconut husk fiber, unactivated and activated charcoals were applied to absorb Cr(III) ions. Optimization of adsorption parameters such as contact time, solution pH, temperature and adsorption isotherm were also studied. The results showed that the optimum carbonization temperature was 600oC, contact time was 5 hours, optimum pH was 6, room temperature. The adsorption capacity of Cr(III) ions were 8.2580 mg/g, 13.5645 mg/g and 16.1452 mg/g for coconut husk fiber, unactivated and activated charcoal, respectively. The increase in adsorption power from coconut husk fiber to charcoal was 64.36% and from charcoal to activated charcoal increased by 19.02%. Coconut husk fiber and unactivated charcoal followed the Langmuir isotherm while activated charcoal followed Freundlich.

Experimental and theoretical investigations into propane dehydrogenation over MIL-101(Cr/Al) derived catalysts

Propane dehydrogenation is commonly operated at temperatures exceeding 600 °C due to thermodynamic requirements. However, high temperature accelerates the deactivation of catalysts because of the coke deposition. Therefore, it is quite necessary to develop catalysts with high catalytic activity and improved anti-coking ability. To this end, an Al-doped Cr2O3 catalyst derived from MIL-101(Cr/Al) is prepared in this work. The preparation conditions, including the carbonization temperature of MIL-101 and the proportion of Cr/Al, are optimized via experimental studies. Meanwhile, the adsorption and dehydrogenation behaviors of propane on the catalyst are investigated using Density Functional Theory (DFT) methods. Findings indicate that the optimum carbonization temperature and Cr/Al proportion are 900 °C and 6:4, respectively. Under the reaction condition of P = 0.1 MPa, T = 580 °C and GHSV = 800 h−1, the propane conversion and propylene selectivity on the Cr6/Al4 catalyst are 19.5% and 92.0%, respectively. The activity stability of the Al-doped Cr2O3 is elongated significantly due to the lower desorption energy of propene and higher energy barrier for the coke formation on the catalyst. In sum, the present work completed via experiments and DFT calculations will lead to a better understanding of the Al-doped Cr2O3 catalyst and guide the rational design of anti-coking catalysts for propane dehydrogenation.

Fabrication of robust CaO-based sorbent via entire utilization of MSW incineration bottom ash for CO2 capture

CO2 capture using CaO-based sorbent is a promising and effective CO2 mitigation strategy due to its high theoretical capacity of CO2 adsorption and potential use in large scale. The preparation of waste-derived CaO-based CO2 sorbents has received extensive interests due to its economic feasibility via waste recycling. In this work, the development of a novel robust CaO-based sorbent via the entire utilization of municipal solid waste incineration (MSWI) bottom ash (BA) was reported. Specifically, residues from the extraction of CaO from BA were added back to the extracted CaO after thermal passivation. The results showed that the addition of BA residue-derived stabilizer (BAS) promoted the homogeneous dispersion of CaO and increased the specific surface area (17.66 m2/g) of the BAS/CaO sorbents and pores in the range of 20–100 nm. Meanwhile, the small amounts of Al2O3 and SiO2 in the Ca-Si-Al-O species of BAS reacted with CaO to form Ca12Al14O33 and Ca2SiO4 during cyclic carbonation/calcination, which was beneficial to alleviate the aggregation and sintering between CaO particles and maintain porous structure of sorbents. In addition, the CO2 uptake exhibited a volcano-type variation with the increase of BAS additive amount and carbonation temperature, where the optimum carbonation temperature for BAS(20 wt%)/CaO sorbents was 700 °C. Among the various sorbents, the BAS(20 wt%)/CaO sorbent (BAS/CaO = 2/8) exhibited the most superior CO2 uptake of 0.14 gCO2/gsorbent after 20 cycles. This study provides a promising method to achieve a cost-effective CO2 capture candidate with enhanced capacity by completely reusing solid wastes, which eliminates the disposal of secondary residues that was rarely considered in previous studies.

A facile one pot synthesis of biocarbon derived from water hyacinth and development of pellets for CO2 capture applications

In the present work, porous biocarbon with inherent nitrogen is synthesized using a noxious aquatic weed, water hyacinth (Eichhornia crassipes) using a facile and green route. A one-step ZnCl2 activation method, using minimum amount of activating agent at different carbonization temperatures 500 and 600 °C were employed for the production of water hyacinth biocarbon to study the effect of temperature on CO2 adsorption capacity. It is observed that by maintaining an optimum carbonization temperature, the microporosity as well as the nitrogen moieties on the carbon surface can be tuned which in turn influences the CO2 adsorption capacity. The obtained biocarbon was pelletized using non-toxic binders such as sepiolite and carboxymethyl cellulose (CMC) and the effect of binders on thermal stability as well textural properties was evaluated. It is observed that there is a reduction in surface area as well as micropore volume after binder addition due to pore blockage which caused a decline in CO2 adsorption capacity. The water hyacinth biocarbon shows maximum adsorption capacity of 3.2 mmol/g, while water hyacinth biocarbon pellets possess maximum adsorption capacity of 2.6 mmol/g at 298 K and 3 bar. To the best of our knowledge, the development of pellets from water hyacinth as well as its utilization for CO2 capture has not been explored yet.

Evaluation of Activated Carbon from Raphia Palm Nut Endocarp as Adsorbent for Solid Adsorption Refrigeration

Activated carbon was produced from powdered Raphia palm nut endocarp (REAC) using H3PO4 and CaCl2 as activators before carbonization, and the responses studied to investigate its suitability for solid adsorption refrigeration applications. Temperature, resident time, concentration, and impregnation ratio, were the parameters used and ash content, carbon yield and surface area were the responses. The effect of preparation sequence was evaluated. The efficiency of the activated carbon on the adsorption of methanol was investigated an experimental rig. 100 g of sample was carbonized at 200, 400 and 600oC, and the carbonized samples were used for solid adsorption refrigeration to determine the optimum carbonization temperature. Carbonization times (30, 60, 90, and 120 minutes), activating agent concentrations (25, 50, 75 and 100%) and impregnation ratios (1:1, 1:2, 1:3, and 1:4 precursor to activating agents) at the optimum temperature were used to determine the optimum resident time, concentration and impregnation ratio. The results revealed that H3PO4 activated samples at optimum conditions of 500˚C temperature, 50% concentration, 60 minutes resident time and 4 ml/g impregnation ratio yielded better response with low percentage of ash content (2.25%), high carbon yield (73.63%) and large surface area (2857.51 m2/g) activated carbon were obtained at the optimum conditions. The adsorbing efficiencies of the carbons prepared through activation with H3PO4 achieved 0.084 and 14.5 of Coefficient of Performance (COP) and Specific Cooling Power (SCP) respectively. The results indicated that the carbon is activation before carbonization is well suited solid adsorption refrigeration applications.

Synthesis Optimization of Activated Carbon Driven from Scrap Tire for Adsorbent Yield and Methylene Blue Removal under Response Surface Methodology

This study aimed to investigate the synthesis optimization of activated carbon-driven scrap tires for adsorbent yield and methylene blue removal under response surface methodology. The scrap tire sample was activated by KOH using ethanol as a solvent. The optimized activated carbon was characterized using proximate analysis, scanning electron microscope (SEM), X-ray diffraction (XRD), and Brunauer Emmett Teller (BET) method. The activated carbon was demineralized using 5 M NaOH + 98% H2SO4 (1 : 1) as a solvent to enhance the surface area. Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich models were used to check the adsorption isotherm. The adsorption kinetics was checked using pseudo-first-order and pseudo-second-order models. Weber-Morris intraparticle diffusion model was used to study the diffusion mechanism. The optimum impregnation ratio, impregnation time, and carbonization temperature for synthesizing the activated carbon were 2 g/g, 12 hr, and 700°C, respectively. The moisture content, volatile matter, ash content, fixed carbon, and bulk density of the activated carbon were 6.13%, 9.42%, 5.34%, 79.11%, and 0.89 mg/L, respectively. The surface area of optimized activated carbon was enhanced by demineralization process and increased from 53 m2/g to 260.26 m2/g. Temkin adsorption isotherm with R2 values of 0.982 and pseudo-second-order adsorption kinetics with R2 values of 0.999 best fits the experimental data respectively. Intraparticle diffusion was not the only rate-controlling step for both optimized and demineralized (NaOH + H2SO4) activated carbon. It can be concluded that the optimized and demineralized activated carbon derived from scrap tires has a promising potential to be used as a low-cost adsorbent in developing countries including Ethiopia. However, further investigation needs to be conducted before scaling up at industrial level.

Biochar mitigation of soil acidification and carbon sequestration is influenced by materials and temperature

The alleviation effects on soil acidification by different raw materials and pyrolysis temperatures can broaden the utilization of biochar. In this study, nine types of biochar produced from three raw materials, namely fruit tree branch, peanut shell, and cow dung, at three pyrolysis temperatures (300, 450, and 600 °C) were used to amend acidified brown soil; the rape growth, physiology character, soil chemical and microbial, along with soil organic carbon mineralization were also investigated. The results showed that application of biochar increased soil pH by 8.48–79.25% and reduced exchangeable acidity, exchangeable Al, and exchangeable H by 56.94–94.95%, 34.38–95.66%, and 58.72–93.27%, respectively. Biochar alleviated oxidative stress in plants, reduced malondialdehyde and glutathione content in leaves, promoted rape growth, and increased microbial community diversity and the relative abundances of Acidobacteria and Olpidiomycota in the acidic soil. Moreover, biochar reduced the mineralization rate of organic carbon and the proportion of mineral-bonded organic carbon. Overall, biochar application is an effective strategy to ameliorate soil acidification and enhance rape production and carbon sequestration. The mitigation effect of branch biochar and cow dung biochar on soil acidification was superior to that of peanut shell biochar. The effects of biochar depended on the pyrolysis temperature; the positive effects of biochar samples pyrolyzed at 450 and 600 ℃ were stronger than those pyrolyzed at 300 ℃. In this study, the optimum biochar materials and carbonization temperature for acidified soil improvement, as well as the effects of biochar application on soil microbial and carbon mineralization were clarified, which provides a new potential strategy for acidified soil improvement and expand the application range of biochar.

Modification of activated carbon of rice husk using HDTMA-Br (SMAC) surfactant as nitrite ion (NO2 −) adsorbent

Surfactant modified activated carbon (SMAC) is a product resulting from the modification of activated carbon with surfactants to increase the adsorption ability of activated carbon against ions in water. Carbonization using pyrolysis at 300°C, 350°C, and 400°C. Activation of carbon was carried out in two ways, the first activation using H3PO4 activator, followed by heating at 410°C for 1 hour. Second, activation using H3PO4 followed by radiation with microwaves. The resulting activated carbon was modified with HDTMA-Br to form SMAC, then SMAC was applied for adsorption of nitrite (NO2 −) ions. This study aimed to determine the optimum conditions for carbonization temperature, radiation time, radiation power, adsorption time of HDTMA-Br. The adsorption capacity of SMAC on nitrite ions and the adsorption process of HDTMA-Br were studied (thermodynamic data). Characterization was carried out using FTIR, SEM, and GSA. The optimum carbonization temperature was 300°C; the optimum activation was 5 minutes and 400 watts, the optimum time for HDTMA-Br adsorption was 4 hours with the adsorption capacity was 7.304 mg/g. SMAC is effective in adsorbing nitrite ions where the adsorption capacity was 0.741 mg/g, and the adsorption efficiency is 98.833%. The adsorption of HDTMA-Br on activated carbon was physical adsorption, SMAC has an N-(CH3)3 group from HDTMA-Br with a SMAC surface area of 24.173 m2/g.

Synergetic Strategy for the Fabrication of Self-Standing Distorted Carbon Nanofibers with Heteroatom Doping for Sodium-Ion Batteries.

Currently, the limited availability of lithium sources is escalating the cost of lithium-ion batteries (LIBs). Considering the fluctuating economics of LIBs, sodium-ion batteries (SIBs) have now drawn attention because sodium is an earth-abundant, low-cost element that exhibits similar chemistry to that of LIBs. Despite developments in different anode materials, there still remain several challenges in SIBs, including lighter cell design for SIBs. The presented work designs a facile strategy to prepare nitrogen-doped free-standing pseudo-graphitic nanofibers via electrospinning. A structural and morphological study implies highly disordered graphitic structured nanofibers having diameters of ∼120–170 nm, with a smooth surface. X-ray photoelectron spectroscopy analysis showed that nitrogen was successfully doped in carbon nanofibers (CNFs). When served as an anode material for SIBs, the resultant material exhibits excellent sodium-ion storage properties in terms of long-term cycling stability and high rate capability. Notably, a binder-free self-standing CNF without a current collector was used as an anode for SIBs that delivered capacities of 210 and 87 mA h g–1 at 20 and 1600 mA g–1, respectively, retaining a capacity of 177 mA h g–1 when retained at 20 mA g–1. The as-synthesized CNFs demonstrate a long cycle life with a relatively high Columbic efficiency of 98.6% for the 900th cycle, with a stable and excellent rate capacity. The sodium storage mechanisms of the CNFs were examined with various nitrogen concentrations and carbonization temperatures. Furthermore, the diffusion coefficients of the sodium ions based on the electrochemical impedance spectra measurement have been calculated in the range of 10–15–10–12 cm2 s–1, revealing excellent diffusion mobility for Na atoms in the CNFs. This study demonstrates that optimum nitrogen doping and carbonization temperature demonstrated a lower Warburg coefficient and a higher Na-ion diffusion coefficient leads to enhanced stable electrochemical performance. Thus, our study shows that the nitrogen-doped CNFs will have potential for SIBs.

Investigation on the fast carbon dioxide sequestration speed of cement-based materials at 300 °C–700 °C

In recent years, the increasing global temperature, caused by excessive carbon dioxide emission, has put a significant threat on the earth’s environment. Therefore, the development of fast carbon dioxide sequestration technologies is urgently needed. In this study, a high-temperature carbonation technique has been proposed by using cement-based materials. The carbon dioxide sequestration efficiencies of cement paste were tested and evaluated from 300 °C to 700 °C, exhibiting different characteristics compared with that at ambient temperature, with optimum carbonation temperature at 600 °C. The operating parameters, such as carbonation time, sample size, vapor content, and water to cement ratio, which play a significant role in the carbonation reaction, have also been investigated and compared with that at ambient temperature. It was found that the high efficiency of carbon dioxide sequestration could be achieved in the samples with large size and low water to cement ratio.

Bimetallic MOFs-derived yolk-shell structure ZnCo/NC@TiO2 and its microwave absorbing properties

Bimetallic MOFs with core–shell morphology are prepared by feeding step by step. Sandwich type ZIF-67@ZIF-8@TiO2 is prepared by coating TiO2 shell layer on the surface of the obtained ZIF-67@ZIF-8 via hydrolysis technology. After pyrolysis of ZIF-67@ZIF-8@TiO2, ZnCo/NC@TiO2 composite wave absorber with yolk-shell structure is fabricated. The evaporation of zinc, volatilization of organic components and shrinkage of carbon layer at high temperature result in a larger cavity between the core and shell. Large specific surface area, pore volume and cavity structure are favorable for multiple interface reflection. Existence of multiple heterogeneous interfaces, unevenly distribution of space charges accumulated between the interfaces, abundant crystal defects and doped atoms lead to the continuous occurrence of interface/dipole polarization. These make the absorber exhibits excellent microwave absorption performance. The study shows that under the optimum carbonization temperature (700 ℃) and filler content (37%), minimum reflection loss (RLmin) of ZnCo/NC@TiO2 reaches −46.21 dB@9.5 GHz with a matching thickness of 2.8 mm. Meanwhile, by adjusting the thickness of absorber, the effective bandwidth can cover 4.3–18 GHz. Maximum effective absorption bandwidth is up to 4.5 GHz. This work will provide a new strategy for the effective construction of yolk-shell microwave absorbing materials derived from bimetallic MOFs as well as performance optimization of existing microwave absorbing materials.

Effects of chemically treated and carbonized spear grass fibre on the curing and mechanical properties of natural rubber vulcanizates

Effects of chemically treated and carbonized spear grass fibre on the curing and mechanical properties of natural rubber vulcanizates were carried out. Natural rubber (NR) was filled with carbonized (at carbonization temperatures of 400°C, 600°C and 800°C respectively) and chemically treated (treatment with HCl and NaOH of 5% concentration) spear grass fillers respectively, at a filler loading of 30phr. The rubber compounding was carried out in a bambury mixer. The effect of carbonization temperature and chemical treatment of the filler on the mechanical properties (tensile strength, % elongation, hardness strength, abrasion resistance and compression set) and rheological properties (cure time, scorch time, maximum and minimum torque) were carried out on the samples. The results of the mechanical properties of carbonized spear grass fibre (C-SGF) filled vulcanizates show that the optimum carbonization temperature for an improved tensile strength, % elongation, hardness, abrasion and compression set was obtained at 400°C. NaOH treated fibre filled vulcanizates showed better mechanical properties; with the highest abrasion resistance of 67.65%, while untreated and acidified fibre filled vulcanizates showed poor mechanical properties. Acidified (HCl) uncarbonized spear grass fibre (U-SGF) filled vulcanizate had the highest compression set of 48% against C-SGF filled vulcanzates and carbon black filled vulcanizate, with carbon black filled vulcanizate having 47% as its compression set value. This reveals that at a carbonization temperature of 400°C, C-SGF appears to be a potential substitute filler for carbon black (CB).
 Keywords: Spear Grass Fibre, Natural Rubber, Chemical Treatments, Cure Characteristics, Mechanical Properties, Carbonization

Production and characterization of black charcoal from Bambusa vulgaris (Yellow Bamboo) and potentiality for advance applications

Issues of air and water pollution and necessity of health care are becoming serious problem as the inter country and global industrialization accelerates. Finding solutions and speedy addressing to these problems via sustainable management and expansion of woody and non woody forest crops, extraction, eco and health friendly products development is increasingly important. Environmentally and health friendly bamboo charcoal has greater potential and upcoming demand in the globe. Evaluation of higher carbonation temperature and characterization of charcoal properties compared to traditional carbonation temperature pave the way for modification of surface and absorbance properties of bamboo charcoal and expansion of areas applications. This paper provides a scientific research about the optimum carbonation temperature to produce charcoal from Bambusa vulgaris (yellow bamboo). The bamboo culm was carbonized at four differed temperatures ranging from 600 to 950oC. Products of charcoal were characterized by SEM micrograph analysis, modules of rupture (MOR), calorific value, density, bulk density, density determination and water absorption determination. Optimum carbonization temperature to gain maximum property enhancement of bamboo charcoal was observed around 700 and 850 oC. By changing carbonization temperature charcoal properties can be change. Removal and solidification of carbon in the flue gas during manufacturing and convert into usable foam of product development pave the way for the expansion of charcoal manufacturing industry without harmful damage to the environment.

Synthesis of renewable heterogeneous acid catalyst from oil palm empty fruit bunch for glycerol-free biodiesel production

Interest in biodiesel research has escalated over the years due to dwindling fossil fuel reserves. The implementation of a carbon-based solid acid catalyst in biodiesel production eradicates the separation problems associated with homogeneous catalysis. However, its application in the glycerol-free interesterification process for biodiesel production is still rarely being studied in the literature. In this study, novel environmentally benign catalysts were prepared from oil palm empty fruit bunch (OPEFB) derived activated carbon (AC) which is sustainable and low cost via direct sulfonation using concentrated sulfuric acid. The effects of synthesizing variables such as carbonization and sulfonation temperatures with different holding times towards the fatty acid methyl ester (FAME) yield in interesterification reaction with oleic acid and methyl acetate were investigated in detail. It was found that the optimum carbonization temperature and duration together with sulfonation temperature and duration were 600 °C, 3 h, 100 °C and 6 h, respectively. The catalyst possessed an amorphous structure with a high total acid density of 9.0 mmol NaOH g−1 due to the well-developed porous framework structure of the carbon support. Under these optimum conditions, the OPEFB derived solid acid catalyst recorded an excellent catalytic activity of 50.5% methyl oleate yield at 100 °C after 8 h with 50:1 methyl acetate to oleic acid molar ratio and 10 wt% catalyst dosage. The heterogeneous acid catalyst derived from OPEFB had shown promising properties that made them highly suitable for cost-effective and environmental-friendly glycerol-free biodiesel production.

Activated carbon produced from Glycyrrhiza glabra residue for the adsorption of nitrate and phosphate: batch and fixed-bed column studies

In the present study, Glycyrrhiza glabra residues (GGR) were used for the preparation of activated carbon, with a surface area of 959.22 m2 g−1. Activated carbon was prepared through chemical activation using ZnCl2 at optimum carbonization temperature, and impregnation ratio for nitrate, and phosphate removal. The effect of contact time and adsorbent dosage on the removal efficiency was investigated, and the pseudo-second-order kinetic model correlated well with the adsorption data. The response surface methodology was applied for the determination of the effect of initial concentration, pH, and temperature and their interaction on the removal efficiency in the batch adsorption system. The Langmuir isotherm generated a satisfactory fit with the experimental data, and the maximum adsorption capacity was 142.5 mg g−1 at 308 K and 92.5 mg g−1 at 298 K for nitrate and phosphate removal, respectively. The high adsorption capacity reveals the applicability of the GGR activated carbon for nitrate and phosphate removal. Furthermore, the fixed-bed column adsorption studies were carried out, and the effect of flow rate and influent concentration on the behavior of the breakthrough curve was studied. The breakthrough time decreased by increasing the flow rate and inlet concentration. The Thomas and Yoon–Nelson models were suitable models for the design of GGR activated carbon fixed-bed column. The LUB of 0.44 cm and 4.35 cm was obtained for nitrate and phosphate with the inlet concentration of 20 mg L−1 and a flow rate of 40 mL min−1, respectively. GGR is a new adsorbent that has not been previously utilized for adsorption of phosphate and nitrate.