The Crystal-t Algorithm: A New Approach To Calculate The Sle Of Lipidic Mixtures Presenting Solid Solutions.

Lipidic mixtures present a particular phase change profile highly affected by their unique crystalline structure. However, classical solid-liquid equilibrium (SLE) thermodynamic modeling approaches, which assume the solid phase to be a pure component, sometimes fail in the correct description of the phase behavior. In addition, their inability increases with the complexity of the system. To overcome some of these problems, this study describes a new procedure to depict the SLE of fatty binary mixtures presenting solid solutions, namely the Crystal-T algorithm. Considering the non-ideality of both liquid and solid phases, this algorithm is aimed at the determination of the temperature in which the first and last crystal of the mixture melts. The evaluation is focused on experimental data measured and reported in this work for systems composed of triacylglycerols and fatty alcohols. The liquidus and solidus lines of the SLE phase diagrams were described by using excess Gibbs energy based equations, and the group contribution UNIFAC model for the calculation of the activity coefficients of both liquid and solid phases. Very low deviations of theoretical and experimental data evidenced the strength of the algorithm, contributing to the enlargement of the scope of the SLE modeling.1616740-5

Greener terpene-terpene eutectic mixtures as hydrophobic solvents

Natural products can be the basis for the development of green solvents, relevant for the advancement of new, more sustainable processes and products. In this work, 10 binary mixtures constituted by terpenes are prepared and characterized. Their solid−liquid phase diagrams show that room-temperature solvents can be prepared from solid terpenes in a wide composition range. These diagrams are accurately described by the conductor-like screening model for real solvents, showing it to be a useful predictive tool for the design of novel natural solvents. At the eutectic point, these mixtures possess low viscosities, densities lower than water, and high boiling temperatures. The low water solubility in the eutectic solvents together with its negligible impact on the properties measured is a strong indicator of the hydrophobic character of these mixtures. The tunable character of these mixtures is demonstrated by studying the solvatochromic parameters in the entire concentration region, the properties of the final solvents being tuned by simply varying the mole fraction of the terpenes. The high potential of this tunable character is shown in the selective extraction of dyes from their aqueous solutions. This work is expected to devise new insights concerning these solvents as well as to boost their application in green industrial processes.This work was developed in the scope of the project CICECO-Aveiro Institute of Materials POCI-01-0145-FEDER-007679 (UID/CTM/50011/2019) and Associate Laboratory LSRE-LCM (UID/EQU/50020/2019), funded by national funds through FCT/MCTES (PIDDAC). FCT is also acknowledged for funding the project DeepBiorefinery (PTDC/AGRTEC/1191/2014). M.A.R.M. acknowledges the financial support from NORTE-01-0145-FEDER-000006 funded by NORTE2020 through PT2020 and ERDF. L.P.S. acknowledges FCT for her Ph.D. grant SFRH/BD/135976/ 2018. G.J.M. acknowledges the national funding agencies CNPq (305870/2014-9, 309780/2014-4, 140702/2017-2, 406918/2016-3, 406963/2016-9), FAPESP (2014/21252-0, 2016/08566-1), and FAEPEX/UNICAMP (0125/16).info:eu-repo/semantics/publishedVersio

Measurement and PC-SAFT modeling of solid-liquid equilibrium of deep eutectic solvents of quaternary ammonium chlorides and carboxylic acids

In this study the solid-liquid equilibria (SLE) of 15 binary mixtures composed of one of three different symmetrical quaternary ammonium chlorides and one of five different fatty acids were measured. The experimental data obtained showed extreme negative deviations to ideality causing large melting-temperature depressions (up to 300 K) that are characteristic for deep eutectic systems. The experimental data revealed that cross-interactions between quaternary ammonium salt and fatty acid increase with increasing alkyl chain length of the quaternary ammonium chloride and with increasing chain length of the carboxylic acid. The pronounced decrease of melting temperatures in these deep eutectic systems is mainly caused by strong hydrogen-bonding interactions, and thermodynamic modeling required an approach that takes hydrogen bonding into account. Thus, the measured phase diagrams were modeled with perturbed-chain statistical associating fluid theory based on the classical molecular homonuclear approach. The model showed very good agreement with the experimental data using a semi-predictive modeling approach, in which binary interaction parameters between quaternary ammonium chloride and carboxylic acid correlated with chain length of the components. This supports the experimental findings on the phase behavior and interactions present in these systems and it allows estimating eutectic points of such highly non-ideal mixtures.This work was developed in the scope of the project CICECO e Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (Ref. FCT UID/CTM/50011/2013) and LSRE-LCM, POCI-01-0145- FEDER-006984jUID/EQU/50020/2013, financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. M.A.R.M acknowledges FCT for her PhD grant (SFRH/BD/87084/2012). FCT is also acknowledged for funding the project DeepBiorefinery (PTDC/AGRTEC/ 1191/2014). P.V.A.P., G.J.M., M.D.H. and E.A.C.B thank the national funding agencies CNPq (National Council for Scientific and Technological Development) (305870/2014-9, 309780/2014, 406856/2013-3), FAPESP (Research Support Foundation of the State of S~ao Paulo) (2014/21252-0, 2016/08566-1), FAEPEX/UNICAMP (Fund for Research, Teaching, and Extension) (0125/16) and CAPES (Coordination of Improvement of Higher Level Personnel) for financial support and scholarships. E.A.C thanks Erasmusþ program of the European Union for co-funding.info:eu-repo/semantics/publishedVersio

Enhancing The Description Of Ssle Data For Binary And Ternary Fatty Mixtures

The solid-solid-liquid equilibrium of ternary or multicomponent systems is few explored in literature, due to their complex experimental description, and especially due to their complex modeling. Such a difficult increases in case of organic compounds, such as lipidic molecules, due to the presence of additional peritectic, and metatectic transitions, formation of solid solutions, and polymorphism. In order to fill such a lacuna, two complete SSLE fatty acids binary diagrams (linoleic acid + myristic acid and linoleic acid + stearic acid) were experimentally evaluated and modeled. Also, a third system (myristic acid + stearic acid) presented in literature was modeled, and the SSLE T-x-z phase diagram of the respective ternary system was presented. The melting properties were determined by differential scanning calorimetry, and the activity coefficients of both phases adjusted by excess Gibbs energy models by using the Crystal-T algorithm, proposed in literature. Beyond complete new SSLE experimental data, this work used a new approach for the modeling of the peritectic transition, and presents for the first time the Tammann surface, a tridimensional version of the Tammann triangle for the analysis of the enthalpy of the eutectic transition in the ternary system. (C) 2016 Elsevier B.V. All rights reserved.42611913010th Iberoamerican Conference on Phase Equilibria and Fluid Properties for Process Design (EQUIFASE)2015Alicante, SPAI

In vitro digestion simulation of medium chain fatty acids

Gastric digestion involves physical and chemical processes, which affect food breakdown and nutrient absorption. In vitro digestion studies have been widely used to elucidate the mechanisms of food hydrolyses during digestion. They can be used to evaluate metabolic properties of macronutrients such as lipids. The gastric digestion phase is particularly crucial for digestion of medium-chain fatty acids (MCFA), fatty acids molecules comprised by 8 to 10 carbons, because the stomach also mediates the direct absorption of these components through the gastric mucosa. In this work, the static in vitro digestion protocol [Brodkorb et al., Nature Protocols, 14, (2019) p. 9911014] has been applied to investigate the gastric digestion of medium-chain triglyceride (MCT) oil samples. The total release of free fatty acids (FFA) was measured using a pH-stat device and gas chromatography (GC) was used to obtain FFA profiles. It was observed that 47.93 % of samples FFAs were released during the gastric digestion phase, which is not in accordance with the literature, which establishes 20 % of lipolysis in the gastric digestion. However, it is important to notice that medium-chain fatty acids (MCFA) are preferably metabolized by gastric lipase in the stomach digestion phase. In accordance with the MCT oil composition, GC analyses showed that 97.69 % of FFAs released at the gastric phase are MCFAs, namely, caprylic (50.01 %), capric (32.28 %), and lauric acids (15.39 %). It was noticed that the simulation of the digestion gastric phase it was crucial for determining accurate lipolysis rates in the overall lipid digestion process, particularly when oil samples rich in MCFA were submitted to digestion protocols.FAPESP (grants #2014/21252-0, #2016/08566-1, #2017/16979-7 e #2019/13008-6); CNPq; CAPESinfo:eu-repo/semantics/publishedVersio

Proposing blends for improving the cold flow properties of ethylic biodiesel

Despite the several advantages compared to conventional diesel fuel, the biodiesel has poor cold flow properties, limitng its use as a fuel in moderate and cold climates. Considering that the fatty esters profile and the alcohol used affect the biodiesel physico-chemical behavior, this work explored the crystallization/melting profiles of ethyl biodiesel from different oil sources as well as of binary blends among them to improve their cold flow properties. Therefore, model ethyl biodiesels from soybean oil, beef tallow, palm oil, their fractions, olein and stearin, palm kernel, macauba, and macauba kernel oils were formulated by pure ethyl esters, their melting/crystallization temperature, cloud point, pour point, cold filter plugging point and the fraction of crystallized esters analysed. For all cases, blends decreased the cold flow properties of the heavier biodiesel. Soybean oil and tallow biodiesels, economically relevant sources, presented a CFPP of - 4.28 degrees C and 17.12 degrees C, respectively, whilst some alternative sources, such as macauba and palm kernels biodiesels, presented values lower than -15 degrees C, which is more advantageous in cold climates. Tallow biodiesel was the only not in accordance with Regulation Agencies considering cold climates. Macauba and palm kernel oils were especially interesting to decrease the melting/crystallization temperatures of heavier biodiesels, including those from tallow beef. The best blend was those formulated with soybean and macauba kernel oils with a CFPP lower than - 20 degrees C. This work suggested that not only biodiesels mainly composed by unsaturated esters but also by short-saturated esters could significantly improve the cold flow properties of high saturated biodiesel, being a low-cost and feasible alterative2535059CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP305870/2014-9; 406963/2016-9não tem2014/21252-0; 2016/10636-8; 2016/08566-1; 2017/16979-7The authors thank the national funding agencies, the São Paulo Research Foudation (FAPESP), Brazil (grant #2014/21252-0, grant #2016/10636-8, grant #2016/08566-1, and grant #2017/16979-7), the National Council for Scientific and Technological Development (CNPq), Brazil (grant #305870/2014-9, and grant #406963/2016-9), and the Education, Research and Extension Support Fund of UNICAMP (FAEPEX), Brazil, (grant #0125/16) for their financial support and scholarships. This study was also financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 00

Deacidification of amazonian pracaxi (pentaclethra macroloba) and patawa (oenocarpus bataua) oils: experimental and modeling of liquid-liquid extraction using alcoholic solvents

This paper presents a study about the deacidification of typical Amazonian oils, namely, patawa and pracaxi oils. The liquid–liquid extractions were carried out using three alcoholic solvents: anhydrous ethanol, azeotropic ethanol, and azeotropic isopropanol at 298.15 K and atmospheric pressure. Liquid–liquid equilibrium data for the oils + oleic acid + solvents systems were determined. The azeotropic ethanol was found to be the best extractant for removing free fatty acids (FFAs) since its use provided the highest selectivity values (from 62.98 to more 1.53 × 103), reasonable distribution coefficients (from 1.06 to 1.47), and reduced loss of neutral oil (oil concentrations lower than 1.49 wt% in the alcoholic phases). Moreover, the obtained experimental data were correlated using the nonrandom two-liquid (NRTL) and universal quasi chemical (UNIQUAC) activity coefficient models. The deviations between calculated and experimental values ranged from 0.39 to 1.22 and from 0.28 to 1.10 for the various studied systems using the UNIQUAC and the NRTL models, respectively. Such results indicate the positive perspective of using the liquid–liquid extraction technique for patawa and pracaxi oils refining and the feasibility of using ethanol as an FFA extractant37783794CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP305870/2014-9; 406963/2016-9não tem2014/21252-0; 2016/08566-1; 2017/23670-2; 2017/16979-7; 2018/15737-

Enzymatic Degumming of Rice Bran Oil Using Different Commercial Phospholipases and Their Cocktails

Rice bran oil is a highly nutritious vegetable oil, as it is rich in tocols and γ-oryzanol. Degumming is the first step in the vegetable oil refining process, and its main objective is the removal of phospholipids or gums. In the present study, enzymatic degumming trials were performed on crude rice bran oil using the phospholipases PLA1, Purifine® PLC, their mixture (PLA1/PLC), and a cocktail known as Purifine® 3G. Enzymatic degumming applying 50 mg/kg of PLA1 for 120 min resulted in a residual phosphorus content of 10.4 mg/kg and an absolute free fatty acid increase of 0.30%. Enzymatic degumming applying 300 mg/kg of Purifine® PLC for 120 min at 60 °C resulted in a residual phosphorus content of 67 mg/kg and an absolute diacylglycerol increase of 0.41%. The mixture of phospholipases and the cocktail presented approximately 5 mg/kg of residual phosphorus content after the reaction times. For all degumming processes, the preservation of minor components such as tocols and γ-oryzanol were observed. These results indicate that the use of enzyme mixtures or their cocktails to attain low phosphorus content and high diacylglycerol/free fatty acid conversion during enzymatic degumming is a viable alternative