Brazilian Journal of Chemical Engineering This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Effect of ecofriendly bio-based solvents on oil extraction from green coffee bean and its industrial press cake
Abstract Oil recovery, retention index, and thermodynamic parameters of green coffee beans (GCB) and its press cake (PC) extraction using bio-based solvents were investigated. The extraction parameters investigated were temperature (35 to 55 °C), type of material (coffee beans and press cake), and type of solvent (ethanol, acetone, and ethyl acetate), at a fixed solvent to solid mass ratio (5:1) (w/w). The fatty acid profile of the ethanolic extract was assessed for both GCB and PC, and compared to the oil obtained from the mechanical pressing. It was observed that higher temperatures affected positively the extraction yi...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

Effect of cyclopentane hydrates on the stability of dodac and aot structures
In this study, hydrate formation was induced in two different systems, one obtained with the cationic surfactant DODAC (dioctadecyldimethylammonium chloride), water, mineral oil and cyclopentane, and the other with the anionic surfactant AOT (di-(2-ethylhexyl) sulfosuccinate of sodium), water and cyclopentane. The surfactants used can form emulsions or self-associated systems, depending on compositions and concentrations of the substances that are present in the samples. The stability of the hydrates formed in the different structures was analyzed. Moreover, we also perform a study of the stability of the structures obtain...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

MEASUREMENTS AND THERMODYNAMIC MODELING OF VAPOR-LIQUID EQUILIBRIA FOR BINARY SYSTEMS OF ISOPROPYL CHLOROACETATE WITH CYCLOHEXANE, ISOPROPANOL AND BENZENE AT 101.3 kPa
Abstract In this work, the vapor-liquid equilibrium experimental data for the systems of isopropyl chloroacetate + isopropanol, isopropyl chloroacetate + cyclohexane and isopropyl chloroacetate + benzene were measured by a modi fi ed Rose-type recirculating still under the pressure of 101.3 kPa. The thermodynamic consistency of the measured data was verified by the Herington and van Ness methods, respectively. The experimental data were correlated by the NRTL, Wilson, and UNIQUAC activity coefficient models, and the corresponding interaction parameters of the three models were obtained. The root-mean-square deviations bet...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

Deep eutectic solvents based on betaine and propylene glycol as potential denitrification agents: a liquid-liquid equilibrium study
Abstract Two deep eutectic solvents (DES) based on betaine (B) and propylene glycol (PG) in molar ratios of 1:4 and 1:5 were prepared and their physico-chemical properties were determined. Liquid-liquid equilibria at 298.15 K and atmospheric pressure were determined for 13 quasi-three-component systems with a hydrocarbon (n-hexane, n-heptane, i-octane or toluene), solute (pyridine or thiophene) and DES (B-PG 1:4 or B-PG 1:5). Experimental phase diagrams and calculated distribution ratios showed that DESs are more suitable for denitrification than for desulfurization. The equilibria in the investigated systems were describe...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

VALORIZATION OF Solanum viarum DUNAL BY EXTRACTING BIOACTIVE COMPOUNDS FROM ROOTS AND FRUITS USING ULTRASOUND AND SUPERCRITICAL CO2
In this study, ultrasound-assisted extraction (UAE) and supercritical CO2 extraction (SFE-CO2) were applied to evaluate the extraction yield and chemical composition of fruits and roots matrices of Solanum viarum Dunal. A hydroalcoholic solution (60% ethanol/40% water, v/v) was the solvent used for UAE. For comparisons, extractions with Soxhlet and maceration were carried out. For SFE-CO2, the highest yield was obtained at 60 °C and 250 bar. For UAE, the highest yield was obtained at an ultrasound intensity of 75.11 W/cm2 and pulse cycle of 0.93. The techniques seem to be efficient for the extraction of chemical compounds...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

Maximization of essential oil antioxidant capacity via star anise hydrodistillation
This study shows the innovative approach of optimizing not only EO yield, but also to therapeutic activity. The product obtained follows the principle of the Pure Food and Drug Act and of eco-friendly technology. Also, the best analytical control methodology of the active principle during industrial production was also defined. The AC was found to be dependent on the extraction conditions, and the best antioxidant performance was reported after 3h of hydrodistillation time, using 500 mL distilled water and 8% dry fruits whose granulometry was inferior to 425 μ m. Although all four analytical methodologies used for assessi...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

Modelling ion transport in an amine solution through a nanofiltration membrane
Abstract The performance of a flat sheet polyamide nanofiltration membrane in rejection of a binary mixture of heat stable salts (acetate and sulfate) from methyl-diethanolamine (MDEA) solution was investigated. The effects of pressure and concentration of MDEA solution on rejection of acetate and sulfate ions were studied. At MDEA concentration of 20% wt. and pressure of 70 bar, 80% and 98% rejection can be obtained for acetate and sulfate ions, respectively. Membrane performance and transport coefficients were investigated using the Spiegler-Kedem-Katchalsky (SKK) model, film theory and extended Nernst-Planck (FT-ENP) mo...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

Implication of microwaves on the extraction process of rice bran protein
Abstract During the processing of rice grain, a wide range of by-products are generated, including Rice Bran (RB), which presents rich composition, offering great potential for application in the food and pharmaceutical industries. Thus, the objective of this work was to evaluate the best operating variables in the extraction of rice bran protein through alkaline extraction and Microwave-Assisted Extraction (MAE). It was found that MAE, in similar conditions, resulted in a higher yield of protein extraction and protein content in the extracted material in a relatively shorter process time, when compared to the values obtai...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

Polyetherimide/polyvinylpyrrolidone hollow-fiber membranes for use in hemodialysis
In this study, polyetherimide/polyvinylpyrrolidone (PEI/PVP) hollow fiber membranes (HFMs) were synthesized by the phase inversion method. The synthesized PEI/PVP membranes were characterized by morphological analysis and transport properties (hydraulic permeability and solute rejection coefficient). Their performance in uremic solutes separation was also investigated. Urea removal and clearance were measured. Surface properties were analyzed by infrared spectroscopy (FT-IR), water uptake, zeta potential and protein adsorption. The results showed that PEI/PVP membranes had transport properties comparable to those of curren...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

Chemical regeneration of bone char associated with a continuous system for defluoridation of water
Abstract Sources of fluoride contaminated water are found around the world and their treatment is required before human consumption. This paper contributes to advances in the use of bone-char as an adsorbent for fluoride, associating steps of chemical regeneration and fluoride adsorption in continuous systems, thereby making feasible the multiple use of the adsorbent. Following the development of low cost treatment of water defluoridation in a fixed bed column, using bone-char, regeneration was carried out with NaOH (0.5 mol/L) solution in subsequent adsorption/desorption cycles. The continuous system was modeled applying ...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

SELECTIVE SEPARATION OF Mn(II) AND Cd(II) AS WELL AS REGENERATION OF POLYMER VIA SHEAR INDUCED DISSOCIATION COUPLING WITH ULTRAFILTRATION
Abstract The selective separation of Mn(II) and Cd(II) as well as regeneration of the complexing agent were conducted by shear induced dissociation coupling with ultrafiltration (SID-UF), and the copolymer of maleic acid and acrylic acid (PMA) was used as complexing agent. At the optimal complexation conditions, pH 6 and P/M (mass ratio of polymer to metal ions) 9, both the rejections of Mn(II) and Cd(II) arrived at more than 99%. The shear stabilities of two PMA-metal complexes at different pHs were particularly investigated using rotating disk membrane and the results indicated that critical shear rates γ c of PMA-Mn ...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

Study of the effect of functionalization of carbon nanotubes on gas separation
Abstract In order to improve the adsorption capacity and selectivity of CO2/CH4 and CO2/N2, we have functionalized multi-walled carbon nanotubes (MWCNT) with 3-aminopropyltriethoxysilane (APTES). The functionalized MWCNT was characterized by Fourier transform infrared (FT-IR), energy dispersive X-ray spectroscopy (EDX) and BET analysis. CO2, CH4 and N2 adsorption at two different temperatures and P< 5 bar on the functionalized MWCNTs was investigated by the volumetric method. The selectivity of the functionalized MWCNTs for CO2/CH4 and CO2/N2 was studied and compared with MWCNTs. The functionalized MWCNTs show higher ad...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

A new computational fluid dynamics study of a liquid-liquid hydrocyclone in the two phase case for separation of oil droplets and water
Abstract A liquid-liquid hydrocyclone, so-called de-oiling equipment, was investigated for separation of oil droplets and wastewater in an Iranian petroleum unit. To generate the geometry and the mesh of the hydrocyclone Gambit software was used. Afterwards, by taking advantage of the Euler-Lagrangian principle, the governing equations covering the motion of fluid and that of particles in the hydrocyclone were solved. Initially, it was shown that the outcomes of CFD are in agreement with experimental data, and then 15 hydrocyclones with different overflow diameters, overflow lengths and input velocities were employed for m...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

Catalyst preparation methods to reduce contaminants in a high-yield purification process of multiwalled carbon nanotubes
Abstract CoMo/MgO catalysts with low loading of cobalt and molybdenum were prepared by incipient wetness impregnation and the sol-gel method for high yield production of carbon nanotubes (CNT). A detailed characterization of the catalysts, as-produced CNT and purified CNT, indicated a relationship between carbon nanotube properties, synthesis and purification steps. Excess of molybdenum in the catalyst caused a decrease in carbon yield and produced CNT with a lower degree of graphitization. Catalysts prepared by the sol-gel method and with higher molybdenum loading showed an improved interaction between cobalt and molybden...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research

PREPARATION AND SIMULATION OF THE ON-LINE SiO2/S COATING FOR COKING INHIBITION IN THE INDUSTRIAL CRACKING FURNACE
Abstract Coke formation inside radiant coils is one of the main problems during thermal cracking of hydrocarbons. The on-line preparation of the coating for coking inhibition is a promising technology because it provides more flexibility to the operators on site. The SiO2/S coating was prepared on the inner surface of coils in an 8-year-served GK-VI industrial cracking furnace. The effects of the coating preparation process on the operation of TLE were studied. The coking rates of the tube with and without coating preparation were evaluated by the trend change of tube metal temperature. Simulations of the coating depositio...
Source: Brazilian Journal of Chemical Engineering - January 14, 2020 Category: Chemistry Source Type: research