Synthesis of solid catalyst from dolomite for biodiesel production using palm kernel oil in an optimization process by definitive screening design
Abstract A solid catalyst for biodiesel production was synthesized from dolomite by calcination at different temperatures of 800 and 900oC for 2 h. The catalyst was characterized by scanning electron microscopy (SEM) and Brunauer Emmett Teller (BET). Its performance in the production of palm kernel biodiesel (PKB) using palm kernel oil in an optimization study was carried out by a definitive screening design. The varying process parameters for the optimization were methanol:oil molar ratio, reaction temperature, catalyst quantity, reaction time and dolomite calcination temperature. Tendency and extent of the catalyst reusa...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

STABILITY AND TOXICITY PROFILE OF SOLUTION ENHANCED DISPERSION BY SUPERCRITICAL FLUIDS (SEDS) FORMULATED Andrographis paniculata EXTRACT
Abstract The main objective was to evaluate the stability and toxicity of a Solution Enhanced Dispersion by Supercritical Fluids (SEDS) formulated A. paniculata extract that was intended for food applications. The best formulated SEDS A. paniculata extract with improved dissolution of andrographolide (data not shown) was obtained using 25 mg/mL A. paniculata extract (maceration in acetone) and 6 mg/mL Eudragit L100-55 with acetone as feed solvent at the following SEDS co-precipitation conditions: 150 bar, 40 ̊ C, 15 L/min CO2 flow rate (1 bar, 25 ̊ C), 0.5 mL/min liquid feed flow. Sticky A. paniculata extract with 16% w/...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Epoxidation of jatropha methyl esters via acidic ion exchange resin: optimization and characterization
This study revealed that the maximum 89.9% relative conversion to oxirane rings was achieved after 6 h with the optimal reaction conditions of temperature at 70 ˚ C, the molar ratio of hydrogen peroxide to unsaturation of 1.5 mol, the molar ratio of acetic acid to unsaturation of 0.5 mol, and catalyst loading of 16%. Fourier Transform Infrared (FTIR) spectra of the epoxidized jatropha methyl esters (EJME) showed oxirane peaks (doublet) at 825 and 843 cm-1.1H NMR confirmed the diepoxide group at 2.85 ppm and 2.98 ppm, while the diepoxide signals of 1C NMR were present at 56.88-57.06 ppm. Production of bio-epoxides from Jat...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Conversion of spent fat oil into liquid and gaseous fuels through clinker catalyzed pyrolysis
Abstract Repeated heating of fat oil may result in the formation of highly toxic aldehyde compounds. The oils having such compounds are considered as health hazards and therefore their repeated use is banned in many countries. Since huge quantities of the used oil need urgent disposal, this work is focused on the disposal of used oil for the resource recovery. The waste fat oil was converted into useful fuel through catalytic and non-catalytic pyrolysis. The catalyst was used to lower the oxygen content and to increase the amount of the hydrocarbons in the oil product. The pyrolysis reaction was catalyzed by three catalyst...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

FORMULATION AND CHARACTERIZATION OF ULTRASOUND-ASSISTED NANOEMULSIONS CONTAINING PALM OIL (Elaeis guineensis Jacq) IN WATER
This study aimed to optimize ultrasound-assisted palm oil-in-water nanoemulsions. The influence of hydrophilic-lipophilic balance (HLB), oil and surfactants concentrations, ultrasound intensity and processing time were investigated by means of two experimental designs. Desirability profiles were applied to detect the optimal conditions for preparing the nanoemulsion. Stable nanoemulsions with small droplet size and polydispersity index (PDI) were obtained at an HLB of 6.5, oil and surfactant concentrations of 2.8 wt%, ultrasound intensity of 200 W.cm-2 and processing time of 15 minutes. The nanoemulsion presented stability...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

KINETIC STUDIES OF HYDROLYSIS REACTION OF NaBH4 WITH γ-Al2O3 NANOPARTICLES AS CATALYST PROMOTER AND CoCl2 AS CATALYST
This study mainly focuses on kinetics of NaBH4/Al2O3 nanoparticles (20 nm)/H2O system with CoCl2 as catalyst and the factors that affect the hydrogen generation rate (HGR). It is observed that the reaction rate increases considerably with increase in NaBH4, Al2O3 nanoparticle (20 nm), CoCl2 and NaOH concentrations and the respective reaction orders are calculated. Hydrogen generation rate is also investigated at different temperatures (303, 313, 323 and 333 K) for constant NaBH4 (1.25 moles/L), NaOH (1.4 moles/L), CoCl2 (0.02 moles/L) and Al2O3 (0.09 moles/L) concentrations. Kinetics of the NaBH4 hydrolysis reaction increa...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Production of methyl esters by enzymatic hydroesterification of chicken fat industrial residue
Abstract The feedstock cost can comprise more than 75% of the overall biodiesel cost, and then economic issues are the main limitations of biodiesel production. This research focused on the use of alternative feedstock and production processes. The production of fatty acid esters from residues becomes an interesting alternative route since it is possible to reduce the cost of the process. The present work aimed to produce methyl esters from the residual oil of the poultry industry, using a commercial soluble lipase Eversa Transform 2.0 ® (NS-40116). The effects of methanol (1.2 to 1.8 eqv), water (1 to 2 wt%) and enzyme (...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Hydroxyapatite - carbon nanotube composites for drug delivery applications
Abstract The aim of this study was the synthesis of composites containing hydroxyapatite (Hap) or silicon substituted hydroxyapatite (HapSi), carboxyl functionalized carbon nanotubes (fMWCNT) and gelatin (G) in different ratios. Ibuprofen (IBU) was chosen as a model drug for the formulation of extended-release dosage forms. The obtained composites were characterized using X-ray diffraction, laser diffraction particle size analyzer, Brunauer-Emmett-Teller surface area measurements, transmission electron microscopy and Fourier transformed infrared spectroscopy. IBU adsorption and desorption was monitored by UV-VIS spectrosco...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Evaluation of antioxidant activity of natural extracts on the oxidative stability of cottonseed biodiesel
The objective of this study was to evaluate the antioxidant activity of the natural extracts catechin, curcumin and quercetin on the oxidative stability of methylic cottonseed oil biodiesel. The oxidative stability was evaluated using the Rancimat method (EN 14112) for biodiesel with 500, 1000, 1500, 2000 and 3000 ppm of additives, and compared with the commercial antioxidant butyl hydroxyanisole at the same concentrations. Kinematic viscosity was also evaluated at the same concentration. All additives had a positive effect on the oxidative stability; moreover, all extracts presented better results than BHA. Catechin was t...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Controlled release of theophylline-chitosan composite particles prepared using supercritical assisted atomization
This study investigated the formation of composite particles of chitosan (CS) and theophylline (TPH) via supercritical assisted atomization (SAA) using aqueous ethanol (50%, v/v) as the solvent and supercritical CO2 as the spraying medium. According to XRD, DSC, and FTIR analyses, the crystal form of the SAA-treated TPH from the as-received TPH was unchanged. The effect of different mass ratios of CS to TPH on the in vitro release of TPH showed that the dissolution of the highly water-soluble TPH was retarded when included in the composite particles and could be controlled by the mass ratio of the component in the SAA proc...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Antibacterial activity of zinc oxide nanoparticles synthesized by solochemical process
The objective of this work was to evaluate the antibacterial activity of ZnO-NPs obtained by a solochemical process against important human foodborne pathogens: Staphylococcus aureus, Salmonella Typhimurium, Bacillus cereus and Pseudomonas aeruginosa. ZnO-NPs were identified as nanorods with the length between 90.1 and 100 nm (10.5 % frequency), the diameter between 80.1 and 90 nm (21 % frequency), and wurtzite type crystalline structure. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were equal to 0.05 mg mL-1 and 0.5 mg mL-1 for S. aureus and S. Typhimurium, respectively, lower th...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Thermal performance of one-pass shell-and-tube heat exchangers in counter-flow
Abstract A computational methodology is proposed and applied to calculate the temperature effectiveness, P, and the logarithmic mean temperature difference (LMTD) correction factor, F, of TEMA E shell-and-tube heat exchangers with one-pass and fluids flowing in counter-flow. An arbitrary number of baffles is considered along with three different mixture conditions of the shell-side fluid. The methodology is based on various modeling considerations adopted in several publications addressing crossflow and shell-and-tube heat exchangers. Each section between two baffles is idealized as a crossflow heat exchanger with differen...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Thermal conductivity enhancement of aqueous ionic liquid and nanoparticle suspension
Abstract In the present study, the thermal conductivities of ionic liquid + water in the concentrations 0.1-0.6 %w/w and temperatures (302.5-337.9 K) are determined. The thermal conductivity of aqueous 1-butyl-3-methylimidazolium bromide declined with increasing concentration and temperature. A quadratic model is developed for predicting the thermal conductivity of aqueous ionic liquid using response surface methodology with R2 = 0.99. A two-layered feed forward back propagation neural network 2-10-1 is also modeled with mean square error, root means square and absolute average error percentage of 0.005, 0.071 and 2.684, r...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Prediction of coal slurry pipeline transportation grading reduction and its influence on pipe transportation parameters
Abstract Coal slurry pipe, being a new type of energy transportation mode, changes of the particle composition and the effect on other parameters are worth studying. Comparison of ring tube test measured data and batch grinding model simulation data shows that batch grinding model can predict the coal particle gradation to a certain extent. The effect of collision and wear of overcurrent components in the centrifugal pump, friction and collision between particles and piping and piping accessories, and initial particle size distribution during hydraulic conveying were also investigated by laboratory studies. Meanwhile, the ...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research

Improvement of methane storage capacity in activated carbon bed with bidisperse packing
This study presents a numerical investigation of the dynamics of methane adsorption in granular activated carbon beds with bidisperse packing in order to reduce the void spaces between the adsorbent particles and to improve the storage capacity in adsorbed natural gas vessels. Two distinct particle sizes (d and D) were used for the packing of the bidisperse bed, and the following particle size ratios were investigated: δ = d/D = 1 (monodisperse bed), 1/5, 1/10, 1/15, and 1/20. Compared with the monodisperse bed condition, the results obtained showed that bidisperse packing increases bed density by about 30% and methane s...
Source: Brazilian Journal of Chemical Engineering - October 1, 2019 Category: Chemistry Source Type: research