Two-Stage Adsorber Design for Methylene Blue Removal by Coconut Shell Activated Carbon

The present work was aimed at evaluating the performance of two-stage adsorber for methylene blue removal by coconut shell activated carbon in minimizing the adsorbent mass and contact time. The Langmuir constants were used to evaluate the optimum mass, while the pseudo-second-order constants for contact time. Results show that the adsorbent mass can only be minimized by 0.01 % due to the high adsorbent affinity towards methylene blue, while the contact time has been optimized to 12.2 min at the studied conditions. The effect of adsorbent affinity in two-stage adsorber was analyzed to shed some light about its importance in the design of two-stage adsorber. The performance evaluation was also discussed to bring insight into wastewater treatment applications.

Alternative Materials for the Enrichment of Biogas with Methane

Carbonaceous adsorbents have been pointed out as promising adsorbents for the recovery of methane from its mixture with carbon dioxide, including biogas. This is because of the fact that CO2 is more strongly adsorbed and also diffuses faster compared to methane in these materials. Therefore, the present study aimed to test alternative carbonaceous materials for the gas separation process with the purpose of enriching biogas in biomethane and to compare them with the commercial one. Among them was coconut shell activated carbon (AC) as the adsorbent derived from bio-waste, rubber tire pyrolysis char (RPC) as a by-product of waste utilization technology, and carbon molecular sieve (CMS) as the commercial material. The breakthrough experiments were conducted using two mixtures, a methane-rich mixture (consisting of 75% CH4 and 25% CO2) and a carbon dioxide-rich mixture (containing 25% CH4 and 75% CO2). This investigation showed that the AC sample would be a better candidate material for the CH4/CO2 separation using a fixed-bed adsorption column than the commercial CMS sample. It is worth mentioning that due to its poorly developed micropore structure, the RPC sample exhibited limited adsorption capacity for both compounds, particularly for CO2. However, it was observed that for the methane-rich mixture, it was possible to obtain an instantaneous concentration of around 93% CH4. This indicates that there is still much potential for the use of the RPC, but this raw material needs further treatment. The Yoon–Nelson model was used to predict breakthrough curves for the experimental data. The results show that the data for the AC were best fitted with this model.

LiOH/Coconut Shell Activated Carbon Ratio Effect on the Electrical Conductivity of Lithium Ion Battery Anode Active Material

A lithium ion battery anode active material comprised of LiOH (Li) and coconut shell activated carbon (AC) has been synthesized with Li/AC ratios of (w/w) 1/1, 2/1, 3/1, and 4/1 through the sol gel method. The present study aims to ascertain the best Li/AC ratio that produces an anode active material with the best electrical conductivity value and determine the characteristics of the anode active material in terms of functional groups, surface area, crystallinity, and capacity. Based on the electrical conductivity test using LCR, the active material Li/AC 2/1 had the highest electrical conductivity with a value of 2.064x10-3 Sm-1. The conductivity achieved was slightly smaller than that of the active material with no addition of LiOH on the activated carbon at an electrical conductivity of 5.434x10-3 Sm-1. The FTIR spectra of the activated carbon and Li/AC 2/1 showed differences with in the Li-O-C group absorption at 1075 cm-1 wavenumber and the wide absorption in the area of 547.5 cm-1 that represents Li-O vibration. Based on the results of SAA, the activated carbon had a larger surface area than Li/AC 2/1 at 17.057 m2g-1 and 5.615 m2g-1, respectively. The crystallinity of both active materials was low shown by the widening of the diffraction peaks. Tests with cyclic voltammetry (CV) proved that there was a reduction-oxidation reaction for the two samples in the first cycle with a large charge and discharge capacities of the activated carbon of 150.989 mAh and 92.040 mAh, while for Li/AC 2/1 they were 91.103 mAh and 47.580 mAh.

Comparative Analysis of Activated Carbons from African Teak (Iroko) Wood and Coconut Shell in Palm Oil Bleaching

This study compares the effectiveness of activated carbons from the African Teak/Iroko wood (Milicia excelsia) and coconut shell as adsorbents in Crude Palm Oil (CPO) bleaching. This was done in order to source for local agro-waste substitutes for the imported Fuller’s earth. The materials were activated using analytical grade CaCl2 in 25% solution at a temperature of 109OC in a laboratory hot air oven. The obtained activated carbon samples were subjected to proximate analysis to ascertain their percentage ash, moisture, volatile matter and fixed carbon contents. The CPO to be analysed was degummed, neutralized and further bleached using 2g, 4g, 6g, 8g, 10g, 12g and 14g of the adsorbent samples at a temperature of 130OC after which the obtained oils were analysed and results plotted. It was observed that the bleached oil samples generally had reduced specific gravity, opacity, colour, and free fatty acid (FFA) compared to the CPO. It was also observed that the opacity, colour, and FFA reduced as the adsorbent dosage increased. Conversely, the percentage colour reduction and the percentage FFA reduction increased with adsorbent dosage. Overall, the oil samples bleached by activated carbon from the African Teak/Iroko wood exhibited more desirable properties than the ones bleached by the coconut shell activated carbon.

Characterization of Coconut Shell Activated Carbon Catalyst for the Pyrolysis of Waste Sac Bags into Liquid Hydrocarbon Fuels

Aim: The use of synthetic catalysts in pyrolysis of waste plastics into hydrocarbon fuels is the common practice, these synthetic/ commercial catalysts are not readily available in Nigeria. The aim of this research paper is to prepare and characterize and test the catalytic performance of a locally made catalyst for waste plastic to hydrocarbon fuel pyrolysis. Study Design: locally made catalyst was prepared from coconut shells, its elemental composition, structural morphology and pore properties investigated using appropriate instruments and methods. Place and Duration: The experiments were carried out at the Petroleum Development Laboratory, situated at the Gas Engineering building, University of Port-Harcourt Nigeria. It took about 18 months to complete this study. Methodology: Thermal and chemical activation methods were used to prepare the local catalyst from coconut shells. Scanning electron microscopy method was used to investigate the morphology and texture of the coconut shell activated carbon catalyst. Response Surface Method (RSM) in design expert software 12.0 was used to design the experiment, and investigate the effect of operating parameters on the response variable. Results: The assessment of coconut shell activated carbon shows it can be used as an alternate to synthetic catalysts. This is because more than 60 % fuel oil was recovered when it was used in the pyrolysis of waste sac bags Conclusion: Coconut shell activated carbon is effective in the conversion of waste sac bags high purity hydrocarbon fuels such as aviation kerosene.

Phenol Removal from Aqueous Solution by Adsorption Technique Using Coconut Shell Activated Carbon

Adsorption is one of the simplest techniques with low economic requirements. Coconut shell is an abundant agriculture waste which is inexpensive and easy to be obtained in Malaysia. This agriculture waste was transformed to activated carbon via 600°C of carbonization and zinc chloride activation. The ability of coconut shell-based activated carbon to remove phenolic compounds from aqueous solutions was evaluated. From the experiment, the equilibrium time for the adsorption of phenol onto coconut shell-based activated carbon is 120 minutes. The effect of the operating parameters, such as contact time, initial concentration, agitation speed, adsorbent dosage, and pH of the phenolic solution were studied. Adsorption kinetics models (pseudo-first-order, pseudo-second-order, and Elovich equation) and isotherm models (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich) were used to fit the experimental data.Pseudo-second-order was found to be the best fitted kinetics model to describe the adsorption of phenol on coconut shell-based activated carbon. While the equilibrium experiment data was well expressed by the Temkin isotherm model, The maximum adsorption capacity is determined as 19.02 mg/g, which is comparatively lower than the previous research. Meanwhile, 92% of removal efficiency was achieved by a dosage of 10g/L. Meanwhile, the adsorption of phenol by activated carbon was more favorable under acidic conditions. The favourable isotherm behavior was indicated by the dimensionless separation factor. The functional group and compound class of activated carbon before and after the experiment were determined through the analysis of Fourier-transform infrared (FTIR) spectroscopy.

Perbandingan Interaksi Karbon Aktif dengan Polaritas Minyak Nabati terhadap Karakteristik Pembakaran Premixed

Crude oil consumption has increased since the discovery of crude oil-fueled engine technology. However, the increase in crude oil consumption is not offset by the productivity of the product. This results in a reduced availability of crude oil. One solution found was to use alternative fuels from vegetable oils. Several researches have proven that vegetable oils can be used as fuel. The results of the research found potential in jatropha oil and palm oil. However, jatropha oil and palm oil contain glycerol compounds which can affect the results of its combustion, because glycerol can absorb heat and result in firing more difficult. Based on that, modification and development are needed to support the use of jatropha oil and palm oil as alternative fuels by studying oil polarity and adding catalysts for coconut shell-activated carbon. Jatropha oil has low polarity (C18) which is more volatile than palm oil which has high polarity (C13). The variation used in this research is the addition of activated carbon with a concentration of 0 ppm, 200 ppm, and 400 ppm in each oil. The addition of activated carbon will facilitate evaporation because oil molecules become more reactive more freely.