Tocopherols and phytosterols concentration from vegetable oil deodorized distillater through molecular distillation process

Orientadores: Maria Regina Wolf Maciel, Cesar Benedito BatistellaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuimicaResumo: Resumo: Os tocoferóis e fitoesteróis são componentes minoritários presentes em plantas e óleos vegetais. Os tocoferóis apresentam atividades vitamínicas e propriedades antioxidantes. A vitamina E é composta por 4 tocoferóis (a, b, g e d) e 4 tocotrienóis (a, b, g e d). Os fitoesteróis possuem propriedades anticolesterolêmica e anticarcinogênicas. Uma das principais fontes de tocoferóis e fitoesteróis são os destilados desodorizados de óleos vegetais. Os destilados desodorizados são constituídos de ácidos graxos, triglicerídeos, fitoesteróis, hidrocarbonetos, aldeídos, cetonas, tocoferóis, dentre outros. Neste trabalho foram estudados dois tipos de destiladores moleculares: centrífugo e de filme descendente (agitado). Os destilados desodorizados de óleo de soja, canola e girassol foram processados no destilador molecular de filme descendente. A recuperação de ácidos graxos livres em função da razão entre as vazões das correntes de destilado e de resíduo apresentou o mesmo perfil para os três destilados desodorizados estudados. O destilado desodorizado de óleo de soja, abundante no Brasil, foi processado no destilador molecular centrífugo. O processo de destilação centrífugo foi estudado tanto experimentalmente quanto por simulação. Foi realizado um planejamento fatorial visando analisar o comportamento das variáveis (temperatura do evaporador e vazão de (alimentação). Observou-se que ocorre uma maior eliminação de ácidos graxos livres a altas temperaturas do evaporador e baixas vazões de alimentação. Tanto o processo de destilação molecular de filme descendente quanto o centrífugo duplicaram a concentração inicial de tocoferóis. Através do processo de destilações sucessivas triplicou-se a concentração de tocoferóis e, com destilações sucessivas seguidas de uma etapa de cristalização, quaduplicou-se a concentração de tocoferóis em relação à concentração originalAbstract: Tocopherols and phytosterols are minority compounds present in vegetables oils. Tocopherols show vitaminic activities and antioxidant properties. Vitamin E is composed by four tocopherols (a, b, g and d) and four tocotrienols (a, b, g and d). The phytosterols have anticholesterolemic and anticarcinogenic properties. The main natural sources of tocopherols and phytosterols are the vegetable oil deodorized distillate (VODD). The deodorized distillates are composed by fatty acids, acylglycerols, sterols, hydrocarbons, aldehydes, ketones and tocopherols. In this work, two kinds of molecular distillation equipments were studied: centrifugal and falling film (wiped). The soybean, canola and sunflower oil deodorized distillates were carried out at falling film molecular distilator. The free fatty acids recovery in function of the Distillation mass/Residue mass ratio shows similar behavior to the three VODDs. Soybean oil deodorized distillate, abundant in Brazil, was chosen to be processed in the centrifugal molecular distiller. This centrifugal molecular distillation process was studied experimental and simulated. The factorial design was carried out to analyze the variable behavior (evaporator temperature and feed flow rate). The free fatty acids elimination occurs at higher evaporator temperatures and lower feed flow rate. The falling film and centrifugal molecular distillation process duplicates the tocopherol concentration. Through successive distillations, the tocopherol concentration was three times higher and with the crystallization, the tocopherol concentration was four times in relation to the original concentrationDoutoradoDesenvolvimento de Processos QuímicosDoutor em Engenharia Químic

Otimização de colunas de destilação complexas

Orientador : Maria Regina Wolf MacielDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuimicaResumo: Misturas binárias com comportamento ideal e não ideal são estudadas nesta dissertação. O processo de destilação convencional é estudado para misturas binárias e ternárias ideais. As misturas n-hexano/n-heptano e n-hexano/n-heptano/n-octano foram estudadas. Dois processos de separação são estudados e comparados para a mistura binária não-ideal: destilações azeotrópicas homogênea e heterogênea, as quais apresentam diferentes comportamentos dinâmicos. A mistura etanol/água é considerada para este estudo visando otimização de variáveis para a minimização de energia consumida no processo. Novas alternativas de processo foram estudadas, sob o ponto de vista da substituição de solventes e de projeto. As considerações de substituição do solvente etileno glicol, usado na destilação azeotrópica homogênea e do benzeno, usado na destilação heterogênea, são extremamente importantes do ponto de vista de minimização de geração de poluentes. Estudos de comportamentos dinâmicos dos sistemas foram feitos para os três processos de destilação estudados. Foram perturbadas positiva e negativamente a vazão de alimentação, a vazão de solvente, a composição da corrente de alimentação e a carga térmica do refervedor. Os sistemas ideais apresentaram respostas semelhantes qualitativamente frente às perturbações. Para os sistemas não ideais, as perturbações podem acarretar diminuição na pureza dos produtos, a energia no refervedor pode não ser suficiente para vaporizar a alimentação excedente, podem diminuir a temperatura na base da coluna de destilação. Um comportamento oposto pode ser obtido ao se perturbar a coluna em outra direçãoAbstract: Binary mixtures presenting ideal and non ideal behaviors are studied in this work. The process of conventional distillation is studied for binary and ternary ideal mixtures. The n-hexane/n-heptane and n-hexane/n-heptane/n-octane mixtures were studied. Two processes of separation are studied and compared for the binary non-ideal mixture: azeotropic homogeneous and heterogeneous distillations, which present different dynamic behaviors. The mixture ethanol/water is considered for a study of optimization of many variables to minimize the energy consumed in the process. New alternatives of process were studied, from the point of view of the substitution of solvent. The considerations of substitution of the solvent ethylene glycol, used in the homogeneous azeotropic distillation and of benzene, used in the heterogeneous distillation, are extremely important from the point of view of minimization of generation of pollutants. Studies of dynamic behaviors of the systems were made for the three distillation processes. Positive and negative perturbations were generated in the feed flow, the solvent flow, the composition of feed flow and the heat flow of reboiler. The ideal systems presented similar responses qualitatively front to the disturbances. For the non ideal systems, the disturbances can cause reduction of the products purity, the energy in the reboiler may not be enough to vaporize the exceeding feed, they can also decrease the temperature in the bottom of the column. An opposing behavior can be obtained if the disturbance happens in another directionMestradoDesenvolvimento de Processos QuímicosMestre em Engenharia Químic

Optimization Of Tocopherol Concentration Process From Soybean Oil Deodorized Distillate Using Response Surface Methodology.

Soybean oil deodorized distillate is a product derived from the refining process and it is rich in high value-added products. The recovery of these unsaponifiable fractions is of great commercial interest, because of the fact that in many cases, the valuable products have vitamin activities such as tocopherols (vitamin E), as well as anticarcinogenic properties such as sterols. Molecular distillation has large potential to be used in order to concentrate tocopherols, as it uses very low temperatures owing to the high vacuum and short operating time for separation, and also, it does not use solvents. Then, it can be used to separate and to purify thermosensitive material such as vitamins. In this work, the molecular distillation process was applied for tocopherol concentration, and the response surface methodology was used to optimize free fatty acids (FFA) elimination and tocopherol concentration in the residue and in the distillate streams, both of which are the products of the molecular distiller. The independent variables studied were feed flow rate (F) and evaporator temperature (T) because they are the very important process variables according to previous experience. The experimental range was 4-12 mL/min for F and 130-200 degrees C for T. It can be noted that feed flow rate and evaporator temperature are important operating variables in the FFA elimination. For decreasing the loss of FFA, in the residue stream, the operating range should be changed, increasing the evaporator temperature and decreasing the feed flow rate; D/F ratio increases, increasing evaporator temperature and decreasing feed flow rate. High concentration of tocopherols was obtained in the residue stream at low values of feed flow rate and high evaporator temperature. These results were obtained through experimental results based on experimental design.137-140885-9

Empagliflozin in Patients with Chronic Kidney Disease

Background The effects of empagliflozin in patients with chronic kidney disease who are at risk for disease progression are not well understood. The EMPA-KIDNEY trial was designed to assess the effects of treatment with empagliflozin in a broad range of such patients. Methods We enrolled patients with chronic kidney disease who had an estimated glomerular filtration rate (eGFR) of at least 20 but less than 45 ml per minute per 1.73 m(2) of body-surface area, or who had an eGFR of at least 45 but less than 90 ml per minute per 1.73 m(2) with a urinary albumin-to-creatinine ratio (with albumin measured in milligrams and creatinine measured in grams) of at least 200. Patients were randomly assigned to receive empagliflozin (10 mg once daily) or matching placebo. The primary outcome was a composite of progression of kidney disease (defined as end-stage kidney disease, a sustained decrease in eGFR to < 10 ml per minute per 1.73 m(2), a sustained decrease in eGFR of & GE;40% from baseline, or death from renal causes) or death from cardiovascular causes. Results A total of 6609 patients underwent randomization. During a median of 2.0 years of follow-up, progression of kidney disease or death from cardiovascular causes occurred in 432 of 3304 patients (13.1%) in the empagliflozin group and in 558 of 3305 patients (16.9%) in the placebo group (hazard ratio, 0.72; 95% confidence interval [CI], 0.64 to 0.82; P < 0.001). Results were consistent among patients with or without diabetes and across subgroups defined according to eGFR ranges. The rate of hospitalization from any cause was lower in the empagliflozin group than in the placebo group (hazard ratio, 0.86; 95% CI, 0.78 to 0.95; P=0.003), but there were no significant between-group differences with respect to the composite outcome of hospitalization for heart failure or death from cardiovascular causes (which occurred in 4.0% in the empagliflozin group and 4.6% in the placebo group) or death from any cause (in 4.5% and 5.1%, respectively). The rates of serious adverse events were similar in the two groups. Conclusions Among a wide range of patients with chronic kidney disease who were at risk for disease progression, empagliflozin therapy led to a lower risk of progression of kidney disease or death from cardiovascular causes than placebo