Continuous Production of Biodiesel from Rubber Seed Oil Using a Packed Bed Reactor with BaCl2 Impregnated CaO as Catalyst

The goal of this research was to test barium chloride (BaCl2) impregnated calcined razor clam shell as a solid catalyst for transesterification of rubber seed oil (RSO) in a packed bed reactor (PBR). The waste razor clam shells were crushed, ground, and calcined at 900 °C in a furnace for 2 h to derive calcium oxide (CaO) particles. Subsequently, the calcined shells were impregnated with BaCl2 by wet impregnation method and recalcined at 300 °C for 2 h. The synthesized catalyst was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS),  Brunauer-Emmett-Teller (BET) surface area, and basic strength measurements. The effects of various parameters such as residence time, reaction temperature, methanol/oil molar ratio, and catalyst bed length on the yield of fatty acid methyl ester (FAME) were determined. The BaCl2/CaO catalyst exhibited much higher catalytic activity and stability than CaO catalyst influenced by the basicity of the doped catalyst. The maximum fatty acid methyl ester yield was 98.7 % under optimum conditions (residence time 2.0 h, reaction temperature 60 °C, methanol/oil molar ratio 12:1, and catalyst bed length 200 mm). After 6 consecutive reactions without any treatment, fatty acid methyl ester yield reduced to 83.1 %. The option of using waste razor clam shell for the production of transesterification catalysts could have economic benefits to the aquaculture and food industries. Copyright © 2018 BCREC Group. All rights reserved. Received: 4th October 2017; Revised: 22nd January 2018; Accepted: 25th January 2018; Available online: 11st June 2018; Published regularly: 1st August 2018 How to Cite: Buasri, A., Loryuenyong, V. (2018). Continuous Production of Biodiesel from Rubber Seed Oil Using a Packed Bed Reactor with BaCl2 Impregnated CaO as Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (2): 320-330 (doi:10.9767/bcrec.13.2.1585.320-330

Biosorption of Heavy Metals from Aqueous Solutions Using Water Hyacinth as a Low Cost Biosorbent

In this study, biosorption of Cu(II) and Zn(II) ions from aqueous solutions by water hyacinth fiber was investigated as a function of initial solution concentration, initial biomass concentration and temperature. Solutions containing copper and zinc ions were prepared synthetically in single component and the time required for attaining adsorption equilibrium was studied. The optimum sorption conditions were studied for each metal separately. The adsorption equilibrium data were adequately characterized by Langmuir, Freundlich, Temkin and Dubinin-Radushkevich equations. The equilibrium biosorption isotherms showed that water hyacinth possess high affinity and sorption capacity for Cu(II) and Zn(II) ions, with sorption capacities of 99.42 mg Cu2+ and 83.01 mg Zn2+ per 1 g biomass, respectively. All results showed that water hyacinth fiber is an alternative low cost biosorbent for removal of heavy metal ions from aqueous media. Keywords: biosorption, low cost biosorbent, wastewater treatment, heavy meta

The Photocatalytic Reduction of Hexavalent Chromium by Controllable Mesoporous Anatase TiO 2

Titania (TiO2) nanoparticles with periodical mesopore size (up to 150 Å) have successfully been synthesized by sol-gel template method, using titanium(IV) tetraisopropoxide as a starting precursor and isopropanol as a solvent. Different quantities of activated carbon (0%, 5%, and 10% by weight) were used as templates to control the porosity and particle size of titania nanoparticles. The templates were completely removed during the calcination in air at 500°C for 3 hr. The results showed that the specific surface area of titania is increased with increasing activated carbon content. The optical bandgap of synthesized titania exhibits a blue shift by 0.3–0.6 eV when compared to the reported value for the bulk anatase and rutile phases. The photocatalytic activity of porous titania is determined with its reduction efficiency of hexavalent chromium (Cr6+). The reduction efficiency is optimized under ultraviolet illumination

Continuous Process for Biodiesel Production in Packed Bed Reactor from Waste Frying Oil Using Potassium Hydroxide Supported on Jatropha curcas Fruit Shell as Solid Catalyst

The transesterification of waste frying oil (WFO) with methanol in the presence of potassium hydroxide catalyst supported on Jatropha curcas fruit shell activated carbon (KOH/JS) was studied. The catalyst systems were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and the Brunauer–Emmett–Teller (BET) method. The effects of reaction variables such as residence time, reaction temperature, methanol/oil molar ratio and catalyst bed height in packed bed reactor (PBR) on the yield of biodiesel were investigated. SEM images showed that KOH was well distributed on the catalyst support. The optimum conditions for achieving the conversion yield of 86.7% consisted of a residence time of 2 h, reaction temperature of 60 °C, methanol/oil molar ratio of 16 and catalyst bed height of 250 mm. KOH/JS could be used repeatedly five times without any activation treatment, and no significant activity loss was observed. The results confirmed that KOH/JS catalyst had a great potential to be used for industrial application in the transesterification of WFO. The fuel properties of biodiesel were also determined

The Synthesis of 2D CH3NH3PbI3 Perovskite Films with Tunable Bandgaps by Solution Deposition Route

Nowadays, organo-lead halide is one of the most interesting materials for perovskite solar cells. This is because of its ease of fabrication, long absorption wavelength region, and long diffusion length. In this study, we investigated the bandgap tuning of hybrid mixed-halide perovskite films. The films were prepared by sequential two-step deposition technique, using 5-ammonium valeric acid iodide (5-AVAI), PbI2, and a mixture of CH3NH3I and CH3NH3Br as precursor solutions. The results confirmed the formation of 2D perovskites in the presence of 5-AVAI. The obtained films had higher moisture resistance, better surface coverage, and smaller grain size, compared to the films without 5-AVAI. With the introduction of Br− ions, the change in the lattice parameter was observed. The bandgap was also found to increase with increasing Br− content

The Synthesis of 2D CH3NH3PbI3 Perovskite Films with Tunable Bandgaps by Solution Deposition Route

Nowadays, organo-lead halide is one of the most interesting materials for perovskite solar cells. This is because of its ease of fabrication, long absorption wavelength region, and long diffusion length. In this study, we investigated the bandgap tuning of hybrid mixed-halide perovskite films. The films were prepared by sequential two-step deposition technique, using 5-ammonium valeric acid iodide (5-AVAI), PbI2, and a mixture of CH3NH3I and CH3NH3Br as precursor solutions. The results confirmed the formation of 2D perovskites in the presence of 5-AVAI. The obtained films had higher moisture resistance, better surface coverage, and smaller grain size, compared to the films without 5-AVAI. With the introduction of Br− ions, the change in the lattice parameter was observed. The bandgap was also found to increase with increasing Br− content

Process Optimization of Biodiesel from Used Cooking Oil in a Microwave Reactor: A Case of Machine Learning and Box–Behnken Design

In the present investigation, response surface methodology (RSM) and machine learning (ML) are applied to the biodiesel production process via acid-catalyzed transesterification and esterification of triglyceride (TG). In order to optimize the production of biodiesel from used cooking oil (UCO) in a microwave reactor, these models are also compared. During the process, Box–Behnken design (BBD) and an artificial neural network (ANN) were used to evaluate the effect of the catalyst content (3.0–7.0 wt.%), methanol/UCO mole ratio (12:1–18:1), and irradiation time (5.0–9.0 min). The process conditions were adjusted and developed to predict the highest biodiesel yield using BBD with the RSM approach and an ANN model. With optimal process parameters of 4.94 wt.% catalyst content, 16.76:1 methanol/UCO mole ratio, and 8.13 min of irradiation time, a yield of approximately 98.62% was discovered. The coefficient of determination (R2) for the BBD model was found to be 0.9988, and the correlation coefficient (R) for the ANN model was found to be 0.9994. According to the findings, applying RSM and ANN models is advantageous when optimizing the biodiesel manufacturing process as well as making predictions about it. This renewable and environmentally friendly process has the potential to provide a sustainable route for the synthesis of high-quality biodiesel from waste oil with a low cost and high acid value

Oyster and Pyramidella Shells as Heterogeneous Catalysts for the Microwave-Assisted Biodiesel Production from Jatropha curcas Oil

Microwave-assisted biodiesel production via transesterification of Jatropha curcas oil with methanol using solid oxide catalyst derived from waste shells of oyster and Pyramidella was studied. The shells were calcined at 900°C for 2 h and calcium oxide (CaO) catalyst characterizations were carried out by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscope (SEM), and the Brunauer-Emmett-Teller (BET) surface area measurements. The effects of reaction variables such as reaction time, microwave power, methanol/oil molar ratio, and catalyst loading on the yield of biodiesel were investigated. Reusability of waste shell catalyst was also examined. The results indicated that the economic and environmentally friendly catalysts derived from oyster and Pyramidella shells showed good reusability and had high potential to be used as biodiesel production catalysts under microwave-assisted transesterification of Jatropha curcas oil with methanol

Preparation and Characterization of Reduced Graphene Oxide Sheets via Water-Based Exfoliation and Reduction Methods

This research studied the synthesis of graphene oxide and graphene via a low-cost manufacturing method. The process started with the chemical oxidation of commercial graphite powder into graphite oxide by modified Hummer’s method, followed by the exfoliation of graphite oxide in distilled water using the ultrasound frequency from a laboratory ultrasonic bath. Finally, the oxygen functional groups on exfoliated graphite oxide or graphene oxide were eliminated by stirring in hot distilled water at 95°C, as a replacement for highly toxic and dangerously unstable hydrazine. The results assured that stirring in hot distilled water could give the product of graphene or reduced graphene oxide. The samples were characterized by FTIR, XRD, TGA, Raman spectroscopy, SEM, and TEM methods