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.

Vof simulation of single rising drops in three liquid-liquid extraction systems using csf and css interfacial force models
ABSTRACT In liquid-liquid extraction contractors, mass transfer and stage efficiency are closely related to drop hydrodynamics. In the present study, hydrodynamic simulation of three standard liquid-liquid extraction systems recommended by the EFCE (European Federation of Chemical Engineering) has been investigated. Toluene/water, n-butyl acetate/water, and n-butanol/water with different drop diameters were considered in the simulations, representing systems with high, medium, and low interfacial tension respectively. In the current research, for the first time simulations have been carried out using the VOF-PLIC (Volume o...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

SELECTION OF A MATHEMATICAL MODEL FOR THE KINETICS OF Haemophilus influenzae TYPE B USING AKAIKE’S INFORMATION CRITERION
ABSTRACT Haemophilus influenzae type b (Hib) vaccine is made up from its capsular polysaccharide (PRP). Low productivity of the polysaccharide during cell growth increases the final cost of this vaccine. Hib achieves low levels of cellular concentration in vitro due to the inhibition caused by acetate. The Akaike Information Criterion (AIC) was used in this work for selecting models of microbial growth. The application to the case of the multivariate models is outlined and the procedure is carried out using data from Hib cultures. From 4 models of biomass and 15 of acetate and PRP, one could be selected with great evidence...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

An approach to optimize costs during ultra-low hydrodesulfurization of a blend consisting of different oil streams
ABSTRACT The presence of contaminants in diesel oil is severely controlled. These components affect the diesel properties, causing impacts on the emissions of pollutants and compromising its commercialization. The Brazilian legislation imposes the use of diesel S10. In this work, a hydrotreatment unit fed with multiple diesel streams was optimized using a phenomenological mathematical model. A three-phase model of a tricked-bed reactor was considered. The optimization of the process was performed with the interior point method considering the hydrodesulfurization reaction of diesel. It was proposed to minimize the operatin...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

Golden apple cherry snail shell as catalyst for heterogeneous transesterification of biodiesel
ABSTRACT Calcium oxide catalysts prepared from golden apple cherry snail shell (Pomacea canaliculata) via two steps - deproteination and calcination - were compared: the structure was characterized by XRD and XRF and morphology by SEM. In addition, the effects of reaction time, catalyst loading amount, methanol:oil molar ratio and reaction temperature on the biodiesel yield were measured. The optimum conditions for biodiesel production, 0.8 wt% catalyst loading, 12:1 methanol:oil molar ratio, 65 OC reaction and 6 h reaction time, gave a biodiesel up to 95.2%. Moreover, the catalyst demonstrated high stability, permitting r...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

Poly(hydroxybutyrate-co-hydroxyvalerate) micronization by solution enhanced dispersion by supercritical fluids technique
ABSTRACT Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a biodegradable polymer used for a wide range of applications, especially in biomedical and food industry, for which bioactive compound encapsulation is noteworthy. This work aimed to micronize PHBV by Solution Enhanced Dispersion by Supercritical Fluids technique and evaluate possible changes in polymer crystallinity. A 23 Central Composite Design with 3 central points was used to analyze the in fl uence of pressure, temperature and PHBV concentration on particle size produced. Micronized particles were mostly spherical with sizes from 210 to 720 nm, and fre...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

Bactericidal effectiveness of freeze-cast ceramic filters impregnated with silver nanoparticles
ABSTRACT This work aimed to produce freeze-cast pellets of porous ceramic filters of alumina and kaolinite impregnated with silver nanoparticles and to test the efficiency of bactericidal effects. Silver nanoparticles were characterized by average particle size, zeta potential and TEM. After impregnation, leached water was analyzed by graphite furnace atomic absorption spectrometry (GFAAS) that showed an efficiency of more than 99.9% in silver impregnation. From SEM/EDS, it was possible to observe that the pellets have a homogeneous distribution of silver nanoparticles. A halo of inhibition detected by the disc diffusion t...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

Performance of the catalytic membrane reactors of different pore size with palladium as catalytic phase in hydrogenation and oxidation reactions
ABSTRACT The catalytic membrane reactors (CMR) were prepared using commercial Hollow Fiber Membranes of corundum with 4 nm or 1400 nm pores and impregnated with palladium. The tests performed were phenol hydrogenation, hydrogen peroxide generation to oxidize phenol by advanced oxidation processes and chromium (VI) reduction. Reactions were performed in aqueous solution, at mild temperature and under atmospheric pressure. For all tests, the hydrogen passed through the membrane to be activated with palladium. The test with phenol showed that, in the absence of oxygen, the activated hydrogen reacts with the organic matter, le...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

A novel thin film composite reverse osmosis membrane modified by ionic liquid
ABSTRACT Thin Film Composite Reverse Osmosis (TFC RO) membranes have undergone significant changes since inception; particularly the top polyamide layer has been tuned for optimal performance. The present paper demonstrates the novel approach to alter the polyamide membrane performance by subjecting it to ionic liquids. Ionic liquids 1-Butyl-3-Methylimidazolium Chloride [BMIM][Cl], 1-Methyl-3-Octylimidazolium Chloride [C8MIM][Cl] and 1-Butyl-3-Methylimidazolium Bromide [BMIM][Br] were used to alter the membrane performance. About a 6.5% increase in MgSO4 rejection and about an 87% increase in water-flux were noted when the...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

Study of the reduction process of iron in leachate from nickel mining waste
ABSTRACT A mechanism to convert Fe(III) to Fe(II) by a reduction process could be a solution to the problem of selective separation of metals in extraction processes by using the ion-exchange process. The aim of this research was to reduce Fe(III) to Fe(II) present in leachate from nickel mining waste. Reducing agents used were sodium dithionite and sodium metabisulfite. The potential was decreased in order to quantify the minimum reducing agent that was necessary for conversion. Reaction time, pH, stirring speed and temperature were also studied. Results indicated dithionite was a better reducing agent than metabisulfite ...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

Reduction of soluble organic carbon and removal of total phosphorus and metals from swine wastewater by electrocoagulation
In this study, the effects of operating time (t), current density (CD) and initial pH were investigated for soluble organic carbon (SOC) and total phosphorus (TP) removal from swine wastewater, pretreated in an UASB reactor, using an electrocoagulation process with aluminum (Al) and iron (Fe) electrodes. For the optimal conditions, Cu, Zn, Mn, Fe and Al removal, sludge production and energy consumption were evaluated. The removal efficiencies for the Al electrode were 78%, 96%, 84%, 99%, 65% and 84% for SOC, TP, Cu, Zn, Mn and Fe, respectively. For the Fe electrode the removal efficiencies were 57%, 96%, 81%, 99 % and 61% ...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

Improvement of the biochemical methane potential of food waste by means of anaerobic co-digestion with swine manure
ABSTRACT Food waste (FW) has potential for use by means of anaerobic digestion (AD). However, some characteristics of FW affect process stability and methane (CH4) production. Using biochemical methane potential (BMP) tests, this study assessed the improvement of CH4 production and hydrolysis of FW by means of anaerobic co-digestion (AcoD) with swine manure (SM). Different FW:SM ratios were studied under conditions with (WN) and without (NN) nutrients. The highest CH4 production was obtained for the FW:SM 60:40 ratio in the WN and SN conditions with values of 72.87 and 62.83 mL CH4 g VS-1, respectively. This showed that Ac...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

Isolation and fractionation of humic substances present in water with the use of anion-exchange resins and ultrafiltration
ABSTRACT Natural water treatment requires emphasis on humic substances (HS) removal because of disinfection by-product formation possibilities. Thus, detailed research on HS structure and properties is necessary. Two model solutions of different origin were used in this study. A100, A200, A400, A870 and DEAE-cellulose anion exchange resins were used for the one-stage isolation of HS. Model solutions and eluates from the respective resins were subjected to filtration using regenerated cellulose 1, 5 and 10 kDa MWCO ultrafiltration membranes. The results allowed ranking of analyzed anionites according to the isolation capaci...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

Fractal aggregates evolution during flocculation
ABSTRACT A temporal analysis of fractal aggregates during water flocculation is presented. Water was prepared using kaolin solution and a non-intrusive image-based analysis method was used for two-dimensional fractal dimension assessment (dF). The dF values were determined for aggregates larger than 270 µm from 100 images taken in each combination of velocity gradients (Gf) and flocculation times (Tf). The Gf values of 20, 30, 40, 50 and 60 s-1 and Tf values of 2 to 180 minutes were studied, with a Δ Tf of 1 minute for 2 ≤ Tf ≤ 10 minutes and a Δ Tf of 5 minutes for 10 ≤ Tf ≤ 180 minutes. Results showed that...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

EFFECT OF THE COMBINATION OF ENZYMATIC PREPARATIONS ON THE AQUEOUS EXTRACTION YIELD OF THE OIL FROM THE PULP OF Euterpe oleracea FRUIT
ABSTRACT This work aimed to study the effect of the combination of four commercial enzymatic preparations (Celluclast 1.5 L, Viscozyme L, Ultrazym AFP, and Shearzyme 500 L) on the aqueous extraction yield of the oil from the pulp of Euterpe oleracea fruit. The enzymatic preparations were tested individually and in combinations of two, three and four, in triplicate. The negative control presented the lowest extraction yield (34.91%). The tests performed with the isolated enzymatic preparations presented an average increase in the extraction yield of approximately 30% compared to the negative control, confirming the importan...
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research

CULTIVATION OF Chlorella vulgaris IN MEDIUM SUPPLEMENTED WITH DESALINATION CONCENTRATE GROWN IN A PILOT-SCALE OPEN RACEWAY
This study demonstrates the feasibility of culturing C. vulgaris in an alternative medium based on DC in order to valorize the desalination wastewater through its application to algal mass production. (Source: Brazilian Journal of Chemical Engineering)
Source: Brazilian Journal of Chemical Engineering - March 28, 2019 Category: Chemistry Source Type: research