Preparation Of Activated Carbon Research Articles

Antibacterial effect of activated carbons prepared from some biomasses available in North East India

ABSTRACTIn the current study, activated carbons (ACs) prepared from some biomasses available in North East India were tested for its antibacterial capacity. The biomasses used for the preparation of ACs were rubber wood (Hevea brasiliensis), ramie fiber (Boehmeria nivea) and areca catechu husk (Areca catechu) which are basically lignocellulosic in nature and were selected depending on its robust availability in this part of the country. The ACs showed good bactericidal or killing percentage against the commonly available waterborne pathogen Escherichia coli (around 43%) even without incorporation of any metals in it. The ACs were prepared using a modified chemical and physical activation process which were found to be both highly porous (346.02 to 1998.03 m2/gm) and also possess sharp pointed structure in it which could puncture the bacterial cell wall. Various analytical methods like FTIR, SEM, FESEM, UV-Visible Spectroscopy, BET, and DSC were used to characterize the AC samples. This study will provide further insight into the preparation and utilization of specially prepared ACs which can directly be used for water purification purposes.

The effect of plastic on performance of activated carbon and study on adsorption of methylene blue

Abstract

Preparation of activated carbon from date stones as a catalyst to the reactivity of hydroquinone: Application in skin whitening cosmetics samples

Abstract In this study, the authors report on the use of the date stones as a raw material for the production of activated carbon (AC) using the physical activation. The as prepared activated carbon were first characterized using X-ray diffraction (XRD), Fourier Transform Infra-Red (FTIR) Spectroscopy, Scanning Electron Microscopy (SEM/EDX) and chemical methods, and then used as modifier agents for the carbon paste electrode (CPE) to study the electrochemical behavior of the hydroquinone (HQ). This electrochemical study was carried out using the cyclic voltammetry, the chronoamperometry and the differential pulse voltammetry (DPV). The Box-Behnken experimental design (BBD) of the response surface methodology was employed to investigate the effect of different parameters of the AC preparation on the peak potential of the hydroquinone. The transfer coefficient α, the apparent electron transfer rate constant ks and the electro–catalytic activity K for the redox reaction of the hydroquinone at the surface of the AC-CPE were determined using electrochemical approaches. Differential voltammetric measurements of the hydroquinone at the modified electrode exhibited the linear range of 5.0 × 10−8 mol L−1 to 1.0 × 10−3 mol L−1 with a low detection limit of 3.6 × 10−8 mol L−1. Finally, this method was applied for the determination of HQ in skin whitening cosmetics samples.

Activated carbon preparation with the addition of coke-making by-product—coke powder:Texture evolution and mechanism

Abstract As a by-product of coke-making, the utilization of coke powder is a challenging issue for achieving sustainable development. This study describes the preparation of activated carbon (AC) with the addition of coke powder. The yield and performance of the prepared AC were evaluated, and the structure was also characterized by Brunauer-Emmett-Teller (BET), X-ray powder Diffraction (XRD), and Fourier Transform Infrared Spectrometry (FTIR). Results indicated that the addition of coke powder increased the yield and mechanical strength of AC, other than the unfavorable iodine adsorption. The 5% addition of coke powder was the ideal proportion with the yield and mechanical strength increase at 7.1% and 19%, and the iodine adsorption capacity decrease at 1.7%. The addition of coke powder increased the graphitization and decreased the surface area of AC with little effect on the types of the surface functional groups. The decreased surface area may be attributed to the dense crystalline carbon structure of coke powder, which has lower reactivity with water and prevents the carbon loss and pore development during the steam activation. This study provides an alternative solution for AC production by renewable utilization of coke powder.

Teak Leaf-Based Activated Carbon for Phosphate Removal

The use of detergent predictably causes large quantities of phosphate ion in water bodies. It is considered to trigger eutrophication, that creates a severe reduction in water quality. Adsorption using activated carbon is one of the effective methods for the removal of phosphate from wastewater. Recently, the use of microwave irradiation in activated carbon preparation is a promising alternative to replace conventional heating using a furnace. In this study, the use of microwave heating was compared to conventional heating. The result showed that pore of activated carbon was larger than that of the char and the activated carbon prepared using 30% of ZnCl2 had the adsorption performance higher than that of prepared using 20% of ZnCl2. The optimum adsorption occurred at pH 4 and the equilibrium was reached after 180 minutes. The Langmuir equilibrium model was more appropriate than the Freundlich equilibrium model. While the kinetics model analyzed using pseudo-first-order, pseudo-second-order, internal diffusion, and external diffusion indicated that the pseudo second order was most suitable for the adsorption of phosphate by teak leaf activated carbon.

Physico-chemical characterization of carbonized apricot kernel shell as precursor for activated carbon preparation in clean technology utilization

This paper investigates the ability of waste apricot (Prunus armeniaca) kernel shells (AKS) bio-char prepared by single-step carbonization process at 850 °C (residence time of 1 h) for possible removal of toxic elements and organic micro-pollutants. The experiment that was performed as well as parameters used proved to be optimal for bio-char production as adsorbing medium, where last issue is validated by multiform material characterization techniques. It has been shown that the produced bio-char possess highly-porous morphology features, with large specific surface area (328.570 m2 g−1). The obtained product was characterized by various pore sizes (including super-micropores and mesopores with maximum pore size of 2.24 nm) structures. Preliminary results are indicated that obtained bio-char can shows increased affinity to possible adsorption of the small organic molecule contaminants upgraded by its physico-chemical properties. Cost estimation of AKS bio-char production substantiated its cost effectiveness and its good physical and chemical properties for future design in batch adsorption and regeneration tests. It was established that AKS produced bio-char was 2.5 times cheaper than the commercially available activated carbon. Bio-char exhibits promising removal performances for potential adsorption of heavy metal and organic micro-pollutants from wastewaters systems, as indicated by material textures and spectroscopy measurements.

Biosorption of ibuprofen using functionalized bean husks

The ability of bean husk, an agricultural waste, as a promising adsorbent for sequestering Ibuprofen from aqueous solution was investigated. Bean husk waste was modified using ortho-phosphoric acid. The prepared adsorbent was further characterized using FTIR, SEM, EDX and pHpzc techniques respectively. FTIR revealed prominent functional groups for IBP adsorption, SEM showed several pores on activated bean husk making it suitable for trapping IBP molecules. EDX results of acid activated bean husk has the highest percentage of carbon by weight (84.21%) and (89.02%) by atom, respectively. pHpzc studies revealed that the surface of the prepared adsorbent contains predominantly acidic groups: carboxyl (0.531 mmol/g), phenolic (0.845 mmol/g) and lactonic (0.021 mmol/g) totalling 1.397 mmol/g while basic group has 0.700 mmol/g. Operational parameters such as: contact time, pH, temperature, initial IBP concentrations and adsorbent dose were studied. Optimum IBP adsorption took place at a pH of 4.75. Isotherm studies were conducted using Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models respectively. Langmuir isotherm aligned best with the adsorption data. The maximum monolayer adsorptive capacity of the modified adsorbent was 50.00 mg/g at 50 °C. Four different kinetic models viz; pseudo first order, pseudo second order, Elovich, and Intraparticle-diffusion were used to investigate the kinetic process. Adsorption data fitted the pseudo second order kinetic model most. Thermodynamic parameters revealed that the process is spontaneous and endothermic. The study revealed that bean husk is a good precursor for activated carbon preparation; it is an efficient, readily available, economically friendly alternative for the sequestration of ibuprofen from aqueous solution.

Preparation of Activated Carbon from Mangrove Waste by KOH Chemical Activation

In this study, Mangrove (Rhizophora mucronata) fruit waste which was generated from water-based extraction of natural dyes from this fruit was used as raw material in activated carbon preparation. Carbonization of chopped Mangrove fruit waste was conducted in a batch pyrolyzer for slow pyrolysis at temperature range of 300°C to 335°C and atmospheric pressure. The produced carbon was then soaked with potassium hydroxide (KOH) solution for 24 hours before activation process in an electrical furnace at 400°C for an hour. Effect of KOH concentration on physical characteristics of activated carbon was investigated in terms of moisture content, ash content, surface area, pore diameter, iodine number, and surface morphology. It was observed that the surface area and pore diameter increased with increasing the KOH concentration. Soaking the carbon in 2.5 M KOH provided the highest surface area and pore diameter of activated carbon, which were 1,920.6 m2/g and 5.52 µm, respectively. Also, the iodine number of 1,540.13 mg/g was obtained in correspond to the adsorption capacity.

Optimization of activated carbon preparation from sawdust and plastics using response surface method

Optimization of activated carbon preparation from sawdust and plastics using response surface method

Activated carbon preparation from biomass feedstock: Clean production and carbon dioxide adsorption

The current methods used for the production of activated carbon (AC) are often chemical and energy intensive and produce significant amount of chemical waste. Thus, clean production of AC is important to reduce its overall production cost and to limit the adverse effect on the environment. Therefore, the main aim of this study is to develop a clean method for AC production from woody biomass with low chemical consumption. Herein, this study reports a facile strategy for reducing chemical usages in the production of high-performance AC, by introducing a crucial pre-pyrolysis step before chemical activation of biomass. The ACs prepared were characterised using scanning electron microscopy, Fourier transform infrared spectroscopy, nitrogen and carbon dioxide gas adsorption measurements. All these characterisations indicated that produced ACs have similar physicochemical properties. The strategy reduced chemical use by 70% and produced high-performance ultra-microporous ACs with excellent carbon dioxide adsorption capacity (4.22–5.44 mmol m−2). The facile pre-pyrolysis method is recommended for further research as a cleaner activated carbon preparation method from biomass feedstock.

Optimization of the Activated Carbon Preparation from Avocado Seeds, using the Response Surface Methodology

Avocado seeds based activated carbon was prepared using chemical activation method which consisted of potassium hydroxide treatment. The main factors influencing the preparation of activated carbons at the calcination temperature, the concentration of the activating agent and the duration of calcination were investigated. One used as a mathematical model the response surface methodology to correlate the response. The significant factors identified by the analysis of variance (ANOVA) through the t-test, the Pareto diagram and the diagrams of surfaces. The optimum avocado seeds based activated carbon was obtained by using calcination temperature of 450 oC, concentration of activating agent of 0.3 mol/L and time of calcination of 3.0 h, which resulted to an avocado seed based activated carbon iodine number remove of 1142.1 mg/g and yield of 75.09 %, by mass. The best activated carbon obtained under the previous conditions and the raw biomass was characterized by Fourier transform infrared and Scanning Electronic Microscope.

Kinetic equilibrium and isotherm modelling adsorbed methane assessment on synthesized peek-porous sorbent carbon of sustainable coconut shell kernel

It is important to understand methane (CH4) adsorption onto available biomass surfaces quantitatively for its storage as Adsorbed Natural Gas (ANG). Coconut shell being among the abundant agro-waste in Malaysia has chosen with polyetheretherketone (PEEK) as a precursor for preparation of hybrid activated carbon via microwave induced potassium hydroxide activation for methane storage. M33P15 Porous carbon prepared at 300 Microwave power with 3 min irradiation and 15 wt% amount of PEEK and M33P0 was prepared under the same condition as M33P15 but without addition of PEEK. The porous carbons were used for CH4 adsorption as the interactions between carbon and methane is based the pore diffusion and partly film diffusion. The ideal CH4 adsorption capacities of the activated carbons were conducted using volumetric adsorption equipment at pressures (5-30 bar). The obtained experimental data at initial pH of 8.0 and 9.0 were correlated using linear regression analysis with common adsorption kinetic (Pseudo-first order, Pseudo-second order, Elovich) and isotherm models (Freundlich, Langmuir, Sip, and Toth). The pseudo-second-order kinetics describe the best fitness with a correlation coefficient of 0.9998 for sample M33P15. For adsorption isotherms, Sip model shows better fitness for sample M33P15 with the regression coefficient (R 2 ) 0.9800 and with lowest RSMD value (0.1438) than other models. The findings revealed the potential of kinetic and isotherm models in methane adsorption applications.

Optimization of adsorbent derived from non-biodegradable waste employing response surface methodology toward the removal of dye solutions

The waste tire was used as a precursor to prepare activated carbon, and the effect of different processing conditions on the prepared activated carbon was studied. Response surface methodology coupled with Box–Behnken Design (BBD) has been used to find the optimal experimental parameters for the preparation of activated carbon. Response surface methodology was implemented to evaluate the effects of activation temperature, activation time and impregnation ratio. BBD was used to determine the model for the different levels of activation temperature (400–600 °C), activation time (60–180 min) and potassium hydroxide-to-tire ratio (0.5–1.5). The obtained activated carbon was evaluated based on its ability to remove methylene blue dye from aqueous solution. The influential parameters that affected the quality of the prepared activated carbon were determined by analysis of variance based upon the response variable. The optimum condition obtained for the activated carbon preparation was at an activation temperature of 400 °C, the reaction time of 165 min and potassium hydroxide-to-tire ratio of 1.5. The regression equation obtained was validated which showed a good agreement with the predicted model with a maximum error of 1.5% and R2 value of 0.975.

Sakura-based activated carbon preparation and its performance in supercapacitor applications.

3D porous carbonaceous materials were prepared by combining pre-carbonization and KOH activation with sakura petals as raw materials. The prepared porous sakura carbon (SAC-4) exhibits a high specific surface area, a suitable pore size distribution, a low proportion of oxygen-rich groups and N functional groups, and a partially graphitized phase, which are very beneficial for the electrochemical performance of the material as a supercapacitor electrode. In the activation step, when the mass ratio of KOH to sakura carbon (SC) is 4, a supercapacitor is prepared. A maximal specific capacitance of 265.8 F g−1 is obtained when the current density is 0.2 A g−1. When the current density is 1 A g−1, after 2000 cycles in succession, the capacitance retention rate is excellent and the cycling stability can reach as high as 90.2%. The obtained results indicate that porous carbon prepared with sakura blossom as the raw material is an effective and environmentally friendly electrode material for energy storage.

Optimization of the integral valorization process for orange peel waste using a design of experiments approach: Production of high-quality pectin and activated carbon

The aim of this study was to optimize the integral valorization of orange peel waste by obtaining activated carbon after a process of pectin recovery in recycling of orange peel by transformation to value-added products of pectin extraction and activated carbon preparation. The study was supported by statistical analysis, and the significant factors and optimal conditions were obtained from the statistical analysis. Using a representative sample of orange peel waste, a yield of 29.37% pectin was recovered at the optimal operating conditions (phosphoric acid as the extraction agent, 95 °C as the impregnation temperature and a 2-hour extraction time). Activated carbon (AC) was prepared from the remaining solid residue. The conditions that improve the resulting material quality were H3PO4 [0.6 M] used as the activating agent, an impregnation temperature of 95 °C, a carbonization temperature of 400 °C and 1 h of carbonization time. The obtained AC showed a sorption capacity of 2342.91 mg g−1, a value higher than that reported for commercial activated carbon. Using a model dye chemical, the sorption kinetics and thermodynamics of AC were found to follow a pseudo-second-order rate and the Freundlich models, respectively. Using the process conditions obtained in this study, it was possible to optimize the yield and also obtain good-quality products from valorization of orange peel.

Preparation of lignite-based activated carbon and its flue gas desulfurization performance

Activated carbon (AC) is a porous carbon material with a developed pore structure and large specific surface area, which has been widely used in adsorption, catalysis, energy storage, etc. In this paper, the AC samples were prepared from Huolinhe lignite by the KOH activation method. The effects of the alkali-to-carbon ratio and activation temperature on the yield and surface properties were investigated. The textural and chemical properties of the AC samples were investigated using N2 adsorption-desorption and scanning electron microscopy (SEM). Their desulfurization performances were also studied. With the increase of the alkali to carbon ratio, the yield of AC gradually decreased, the specific surface area first increased and then decreased, and the pore volume gradually increased. With the increase of the activation temperature, the yield of AC decreased, while the specific surface area and pore volume increased. Since the desulfurization of AC was mainly related to the specific surface area and micropores, an alkali-to-carbon ratio of 3 and activation temperature of 800 °C were selected as the optimum conditions of AC preparation. The AC with a specific surface area of 3231 m2 g−1 and micropore volume of 0.948 cm3 g−1 was used for desulfurization. In the flue gas flow rate range of 400–1000 ml min−1, the desulfurization efficiency and desulfurization time of AC decreased with the increase of the flue gas flow rate. With the increase of the SO2 concentration from 1000 to 3000 ppm, the desulfurization time and desulfurization efficiency decreased. When the oxygen content was in the range of 0 to 5%, the increase of the oxygen content was not conducive to the desulfurization process.

Corn cob based activated carbon preparation using microwave assisted potassium hydroxide activation for sea water purification

Corn cob based activated carbons have been made through processes of pre-carbonization and microwave assisted chemical activation. In this study, potassium hydroxides (KOH) are used as an activating agent, which by 5% potassium hydroxides in weight of self-adhesive carbon grain of corn cob are soaked in 150 ml distilled water. Samples are then irradiated using microwave with power of 360, 450, and 720 watt for 15 minutes. The activated carbons are applied for water purification of sea water. Physical and chemical properties of the activated carbon are characterized, including microstructure, surface morphology, heavy metal adsorptions, and pH, temperature and colour of sea water. Analysis of microstructure show that the activated carbons have amorphous structure marked by two ramp peaks at the 2θ around of 22 and 44°, respectively. The morphological surface shows that AC720 has more porous rather than AC360, and AC450. The porous activated carbon of AC720 has the highest heavy metal adsorption of 85,20%, 89,80%, and 70,41% for Ni, Pb, and Zn, respectively corresponding to colour level of 126 PtCo, salinity of 25,6% and pH of 7,41.

Effect of the Feedstock Type on the Volumetric Low-Pressure CO2 Capture Performance of Activated Carbons

Activated carbons (ACs) display attractive gravimetric performance for CO2 capture, but it is unclear which carbon precursor suits preparation of ACs with high adsorption performance on a volumetric basis. Thus, we prepared ACs from five feedstocks (bamboo, rice husk, peanut shell, coconut shell, and anthracite) to study impacts of the feedstock type on the densities, volumetric pore parameters, and volumetric CO2 adsorption performance of ACs. The feedstock type was found to affect tap density of ACs, mainly because ACs possessed different macropore volumes. Because of the influence of tap density, the decreasing order of ACs for volumetric pore parameters was different from that for the corresponding gravimetric parameters. When AC was expected to display a high volumetric fine micropore volume (V<0.7 nm,v and V<1 nm,v), its tap density and gravimetric fine micropore volume should be both high. The feedstock type affected the volumetric CO2 uptakes of ACs at 0.15 and 1 bar, mainly because it changed vol...

Optimized methods for preparing activated carbon from rock asphalt using orthogonal experimental design

This work evaluated three activation methods, physical activation, chemical activation and combined physical–chemical activation, for preparing activated carbon (AC) from rock asphalt. A high carbon content and the low cost of rock asphalt makes it a good possible raw material for the preparation of activated carbon. The objective of this research was to establish what preparation conditions resulted in the AC with the best performance. Orthogonal experimental design was used to optimize preparation conditions. The criteria for evaluating the AC preparation methods were yield, surface area and mercury adsorption performance of the AC samples prepared with each technique. The optimum experimental conditions for AC preparation using the chemical activation method are: a carbonization heating rate of 12 °C min−1, a carbonization temperature of 400 °C, a carbonization time of 60 min, an activation temperature of 850 °C, an activation time of 120 min and a KOH/asphaltene mix rate of 3 (w/w). The potassium hydroxide added in the chemical activation method reduced the formation of volatiles during the carbonization process. The KOH/asphaltene mix rate and the carbonization temperature play a decisive role on the specific surface area and Hg adsorption capacity of AC. The optimum experimental conditions for AC preparation using the combined physical–chemical activation method are: a carbonization temperature of 450 °C, a carbonization time of 40 min, an activation temperature of 800 °C, an activation time of 60 min, a KOH/asphaltene mix rate of 1 and a steam flow rate of 8 g h−1. In the combined physical–chemical activation method, the KOH/C mix rate, activation temperature and steam flow rate are the primary factors affecting the surface area and Hg adsorption capacity. The surface areas of the AC samples prepared under the optimum experimental conditions in the chemical activation method and the combined physical–chemical activation methods were 2834.3 m2 g−1 and 2102.2 m2 g−1, respectively. The physical activation method was not suitable for preparing AC from rock asphalt due to low char yields.

Delignification, Carbonization Temperature and Carbonization Time Effects on the Hydrothermal Conversion of Salacca Peel.

Hydrochar from the hydrothermal treatment of biomass is considered as a potential precursor for activated carbons (AC) which has been widely utilized not only for adsorbents but also for energy storage application. The advantages of hydrochar from hydrothermal treatment include its high Oxygenated Functional Group (OFG) and high porosity. The authors have been working on the biomass conversion for energy storage application. In our study, salacca peel was used as a biomass source. In previous research for the preparation of AC, conventional carbonization and activation methods were used, resulting in a high surface area of AC. In the current research, the authors investigated the biomass conversion in hydrothermal conditions. Water at a subcritical condition (with temperatures of 200, 225 and 250 °C and at a pressure of 50 MPa) and carbonization time of 4, 5 or 6 hours, with or without delignification, were critical in the research to investigate the conversion of salacca peel into hydrochar. The produced hydrochar from 225 °C, 5 h was chemically activated and compared to commercially-AC. The hydrochar and AC were then used as electrodes for the supercapacitor, and capacitance was measured by cyclic voltammetry (CV). The results showed that the capacitance of hydrochar was higher than that of AC while ACs from salacca peel exhibited much higher levels of capacitance compared to commercially-AC.