Extração de ferro da cera de carnaúba utilizando sistemas microemulsionados

The constant search for biodegradable materials for applications in several fields shows that carnauba wax can be a viable alternative in the manufacturing of biolubricants. Carnauba wax is the unique among the natural waxes to have a combination of properties of great importance. In previous studies it was verified the presence of metals in wax composition that can harm the oxidative stability of lubricants. Considering these factors, it was decided to develop a research to evaluate iron removal from carnauba wax, using microemulsion systems (Me) and perform the optimization of parameters, such as: extraction pH, temperature, extraction time, among others. Iron concentration was determined by atomic absorption and, to perform this analysis, sample digestion in microwave oven was used, showing that this process was very efficient. It was performed some analysis in order to characterize the wax sample, such as: attenuated total reflectance infrared spectroscopy (ATR-IR), thermogravimetry (TG), differential scanning calorimetry (DSC), energy dispersive X-ray fluorescence (EDXRF), scanning electron microscopy (SEM) and melting point (FP). The microemulsion systems were composed by: coconut oil as surfactant, n-butanol as cosurfactant, kerosene and/or heptanes as oil phase, distilled water as water phase. The pH chosen for this study was 4.5 and the metal extraction was performed in finite experiments. To evaluate Me extraction it was performed a factorial design for systems with heptane and kerosene as oil phase, also investigating the influence of temperature time and wax/Me ratio, that showed an statistically significant answer for iron extraction at 95% confidence level. The best result was obtained at 60°C, 10 hours contact time and 1: 10 wax/Me ratio, in both systems with kerosene and heptanes as oil phase. The best extraction occurred with kerosene as oil phase, with 54% iron removal

Extração do corante reactive blue 19 utilizando tensoativo não iônico

The generation of effluent from the finishing process in textile industry is a serious environmental problem and turned into an object of study in several scientific papers. Contamination with dyes and the presences of substances that are toxic to the environment characterize this difficult treatment effluent. Several processes have already been evaluated to remove and even degrade such pollutants are examples: coagulation-flocculation, biological treatment and advanced oxidative processes, but not yet sufficient to enable the recovery of dye or at least of the recovery agent. An alternative to this problem is the cloud point extraction that involves the application of nonionic surfactants at temperatures above the cloud point, making the water a weak solvent to the surfactant, providing the agglomeration of those molecules around the dyes molecules by affinity with the organic phase. After that, the formation of two phases occurred: the diluted one, poor in dye and surfactant, and the other one, coacervate, with higher concentrations of dye and surfactants than the other one. The later use of the coacervate as a dye and surfactant recycle shows the technical and economic viability of this process. In this paper, the cloud point extraction is used to remove the dye Reactive Blue from the water, using nonionic surfactant nonyl phenol with 9,5 etoxilations. The aim is to solubilize the dye molecules in surfactant, varying the concentration and temperature to study its effects. Evaluating the dye concentration in dilute phase after extraction, it is possible to analyze thermodynamic variables, build Langmuir isotherms, determine the behavior of the coacervate volume for a surfactant concentration and temperature, the distribution coefficient and the dye removal efficiency. The concentration of surfactant proved itself to be crucial to the success of the treatment. The results of removal efficiency reached values of 91,38%, 90,69%, 89,58%, 87,22% and 84,18% to temperatures of 65,0, 67,5, 70,0, 72,5 and 75,0°C, respectively, showing that the cloud point extraction is an efficient alternative for the treatment of wastewater containing Reactive Blue

Estudo dos parâmetros de extração de fenol de efluentes aquosos por um tensoativo não iônico

Environmental sustainability has become one of the topics of greatest interest in industry, mainly due to effluent generation. Phenols are found in many industries effluents, these industries might be refineries, coal processing, pharmaceutical, plastics, paints and paper and pulp industries. Because phenolic compounds are toxic to humans and aquatic organisms, Federal Resolution CONAMA No. 430 of 13.05.2011 limits the maximum content of phenols, in 0.5 mg.L-1, for release in freshwater bodies. In the effluents treatment, the liquid-liquid extraction process is the most economical for the phenol recovery, because consumes little energy, but in most cases implements an organic solvent, and the use of it can cause some environmental problems due to the high toxicity of this compound. Because of this, exists a need for new methodologies, which aims to replace these solvents for biodegradable ones. Some literature studies demonstrate the feasibility of phenolic compounds removing from aqueous effluents, by biodegradable solvents. In this extraction kind called "Cloud Point Extraction" is used a nonionic surfactant as extracting agent of phenolic compounds. In order to optimize the phenol extraction process, this paper studies the mathematical modeling and optimization of extraction parameters and investigates the effect of the independent variables in the process. A 32 full factorial design has been done with operating temperature and surfactant concentration as independent variables and, parameters extraction: Volumetric fraction of coacervate phase, surfactant and residual concentration of phenol in dilute phase after separation phase and phenol extraction efficiency, as dependent variables. To achieve the objectives presented before, the work was carried out in five steps: (i) selection of some literature data, (ii) use of Box-Behnken model to find out mathematical models that describes the process of phenol extraction, (iii) Data analysis were performed using STATISTICA 7.0 and the analysis of variance was used to assess the model significance and prediction (iv) models optimization using the response surface method (v) Mathematical models validation using additional measures, from samples different from the ones used to construct the model. The results showed that the mathematical models found are able to calculate the effect of the surfactant concentration and the operating temperature in each extraction parameter studied, respecting the boundaries used. The models optimization allowed the achievement of consistent and applicable results in a simple and quick way leading to high efficiency in process operation.

Extração enzimática de óleo e produção in situ de biodiesel a partir da Moringa oleífera Lam

With the growth and development of modern society, arises the need to search for new raw materials and new technologies which present the "clean" characteristic, and do not harm the environment, but can join the energy needs of industry and transportation. The Moringa oleifera Lam, plant originating from India, and currently present in the Brazilian Northeast, presents itself as a multi-purpose plant, can be used as a coagulant in water treatment, as a natural remedy and as a feedstock for biodiesel production. In this work, Moringa has been used as a raw material for studies on the extraction and subsequently in the synthesis of biodiesel. Studies have been conducted on various techniques of Moringa oil extraction (solvents, mechanical pressing and enzymatic), being specially developed an experimental design for the aqueous extraction with the aid of the enzyme Neutrase© 0.8 L, with the aim of analyzing the influence variable pH (5.5-7.5), temperature (45-55°C), time (16-24 hours) and amount of catalyst (2-5%) on the extraction yield. In relation to study of the synthesis of biodiesel was initially carried out a conventional transesterification (50°C, KOH as a catalyst, methanol and 60 minutes reaction). Next, a study was conducted using the technique of in situ transesterification by using an experimental design variables as temperature (30-60°C), catalyst amount (2-5%), and molar ratio oil / ethanol (1:420-1:600). The extraction technique that achieved the highest extraction yield (35%) was the one that used hexane as a solvent. The extraction using 32% ethanol obtained by mechanical pressing and extraction reached 25% yield. For the enzymatic extraction, the experimental design indicated that the extraction yield was most affected by the effect of the combination of temperature and time. The maximum yield obtained in this extraction was 16%. After the step of obtaining the oil was accomplished the synthesis of biodiesel by the conventional method and the in situ technique. The method of conventional transesterification was obtained a content of 100% and esters by in situ technique was also obtained in 100% in the experimental point 7, with a molar ratio oil / alcohol 1:420, Temperature 60°C in 5% weight KOH with the reaction time of 1.5 h. By the experimental design, it was found that the variable that most influenced the ester content was late the percentage of catalyst. By physico-chemical analysis it was observed that the biodiesel produced by the in situ method fell within the rules of the ANP, therefore this technique feasible, because does not require the preliminary stage of oil extraction and achieves high levels of esters

Extração, caracterização e avaliação bioativa do extrato de Rumex acetosa

Studies show the great influence of free radicals and other oxidants as responsible for aging and degenerative diseases. On the other hand, the natural phenolic compounds has shown great as antioxidants to inhibit lipid peroxidation and lipoxygenase in vitro. Among these, is highlighted trans-resveratrol ( 3,5,4 `- trihydroxystilbene ) phenolic compound , characterized as a polyphenol stilbene class. The vegetables popularly known as "Azedinha" (Rumex Acetosa) has trans-resveratrol in its composition and from this, the present work aimed to study on the supercritical extraction and conventional extraction (Soxhlet and sequential) in roots of Rumex Acetosa, evaluating the efficiency of extractive processes, antioxidant activity, total phenolic content and quantification of trans-resveratrol contained in the extracts. Extractions using supercritical CO2 as solvent, addition of co-solvent (ethanol) and were conducted by the dynamic method in a fixed bed extractor. The trial met a 23 factorial design with three replications at the central point, with the variable reply process yield and concentration of trans-resveratrol and pressure as independent variables, temperature and concentration of co-solvent (% v/v). Yields ( mass of dry extract / mass of raw material used ) obtained from the supercritical extraction ranged from 0,8 to 7,63 % , and the best result was obtained at 250 bar and 90 °C using the co-solvent 15% ethanol (% v/v). The value was calculated for YCER a flow rate of 1,0 ± 0,17 g/min resulting in 0,0469 CO2 ( g solute / g solvent ). The results of the mass yield varied between conventional extractions 0,78 % ( hexane) and 9,97 % (ethanol). The statistical model generated from the data of the concentration of trans-resveratrol performed as meaningful and predictive for a 95% confidence. GC analysis on HPLC (High Performance Liquid Chromatography), transresveratrol was quantified in all extracts and concentration values ranged between 0,0033 and 0,42 ( mg / g extract) for supercritical extracts and between 0,449 and 17,046 (mg / g extract) to conventional extractions and therefore, the Soxhlet extraction with ethanol for more selective trans-resveratrol than the supercritical fluid. Evaluation of antioxidant (radical method to sequester 2,2- diphenyl-1- picryl - hydrazyl - DPPH) the supercritical extracts resulted in EC50 values (concentration effective to neutralize 50% of free radicals) of between 7,89 and 18,43 mg/mL , while resulting in a Soxhlet extraction with EC50 values in the range of 6,05 and 7,39 mg/mL. As for quantification of the phenolic compounds (Method Spectrophotometer Folin-Ciocalteau) the supercritical extracts resulted in values between 85,3 and 194,79 mg GAE / g extract, whereas values derived from the Soxhlet extract resulted in values between 178,5 and 237,8 mg GAE / g extract. The high antioxidant activity can not be attributed solely to the presence of phenolic compounds, but the presence of other antioxidants in the existing Rumex acetosa

Obtenção de ferrita de cobalto através de dois métodos de síntese: método de complexação combinando EDTA/Citrato e método hidrotérmico

In this work it was synthesized and characterized the cobalt ferrite (CoFe2O4) by two methods: complexation combining EDTA/Citrate and hydrothermal investigating the influence of the synthesis conditions on phase formation and on the crystallite size. The powders were mainly characterized by x-ray diffraction. In specific cases, it was also used scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), x-ray fluorescence (XRF) and isotherms of adsorption and desorption of nitrogen (BET method). The study of the crystallite size was based on the interpretation of x-ray diffractograms obtained and estimated by the method of Halder-Wagner-Scherrer and Langford. An experimental design was made in order to assist in quantifying the influence of synthesis conditions on the response variables. The synthesis parameters evaluated in this study were: pH of the reaction medium (8, 9 and 10), the calcination temperature (combined complexation method EDTA/Citrate 600°C, 800°C and 1000°C), synthesis temperature (hydrothermal method 120°C, 140°C and 160°C), calcination time (combined complexation method EDTA/Citrate - 2, 4 and 6 hours) and time of synthesis (hydrothermal method 6, 15 and 24 hours). By the hydrothermal method was possible to produce mesoporous powders with high purity, with an average crystallite size up to 7 nm, with a surface area of 113.44 m²/g in the form of pellets with irregular morphology. By using the method of combined complexation EDTA/Citrate, mesoporous powders were produced with greater purity, crystallite size up to 22nm and 27.95 m²/g of surface area in the form of pellets with a regular morphology of plaques. In the experimental design was found that the hydrothermal method to all the studied parameters (pH, temperature and time) have significant effect on the crystallite size, while to the combined complexation method EDTA/Citrate, only temperature and time were significant

Preparo de amostras e métodos para a determinação do teor de óleo essencial de frutos de limoeiro

Objetivou-se avaliar alternativas de preparo da amostra e os métodos quantitativos para a determinação do teor de óleo em frutos de limão. Os tratamentos foram avaliados por meio do delineamento estatístico inteiramente casualizado, em esquema fatorial 2x2x6, com quatro repetições, sendo duas variedades-copa de limoeiro verdadeiro ('Siciliano' e 'Eureka'), dois métodos analíticos para a determinação do teor de óleo (Scott e Clevenger) e seis formas de preparo dos frutos para análise (análise do fruto inteiro; frutos cortados na longitudinal e análise de ¼; frutos cortados na longitudinal e análise de ¹/2; frutos cortados ao meio e análise da parte superior; frutos cortados ao meio e análise da parte inferior; e análise de ²/8 do fruto). O método denominado de Clevenger foi o mais eficiente na determinação do teor de óleo essencial, e as formas de preparo de amostras ½ inferior, ½ superior, ¼ longitudinal e ½ longitudinal dos frutos proporcionaram valores superiores de óleo essencial.

Comparação entre métodos para determinação de carbono orgânico em amostras de solo mensuradas por volume ou massa

O uso da massa (g) ou do volume (cm³) como medida da quantidade de solo para determinação do teor de C orgânico do solo (COS), bem como a utilização de diferentes métodos de determinações analíticas empregados para essa mesma finalidade, pode alterar diretamente a interpretação dos resultados. Este trabalho teve como objetivo comparar os métodos colorimétricos e titulométricos de determinação de matéria orgânica em três solos com diferentes texturas, tomando-se as amostras por massa (pesagem) e por volume (cachimbagem). Houve variação no teor de COS entre os métodos estudados para um mesmo solo. O uso da massa e do volume alterou diretamente a interpretação dos teores de matéria orgânica no solo. Há variações nos métodos de determinação de COS entre solos de diferentes texturas.

Estudo de sistemas microemulsionados utilizando água do mar na recuperação avançada de petróleo

Petroleum exists in the nature in certain underground formations where it is adsorbed into the rocks pores. For the conventional recovery methods usually only 30% of the oil is extracted and this can be credited, basically, to three aspects: high viscosity of the oil, geology of the formation and high interfacial tensions between the reservoir s fluids. The enhanced recovery methods use the injection of a fluid or fluids mixture in a reservoir to act in points where the conventional process didn't reach the recovery rates. Microemulsion flooding, considered an enhanced method, has the purpose to desorb the oil from the rock formation and to attain an efficient displacement of the oil emulsion. With this in mind, this work was accomplished with two main objectives: the study of the parameters effect that influence a microemulsified system (surfactant and cosurfactant types, C/S rate and salinity) and the evaluation of displacement efficiency with the microemulsions that showed stability in the rich aqueous area. For the analyzed parameters it was chose the microemulsions composition used in the recovery stage: 25% water, 5% kerosene, 46.7% of butanol as cosurfactant and 23.3% of BC or SCO cosurfactant. The core plugs of Assu and Botucatu sandstones were appraised in porosity and permeability tests and then submitted to the steps of saturation with seawater and oil, conventional recovery with water and enhanced recovery with the selected microemulsions. The Botucatu sandstone presented better recovery parameters, and the microemulsion composed with BS surfactant had larger recovery efficiency (26.88%)

Extração, caracterização e aplicação do corante de urucum (Bixa orellana L.) no tingimento de fibras naturais

The increasing demand for natural dyes in place of synthetic ones is justified by the non-toxicity or low toxicity of the former. The synthetic dyes are associated with diseases like cancer as well as when released in the environment takes longer to degrade and the intermediates could be still more toxic. The Annatto (Bixa Orellana L.) is a carotenoid and one of the more important natural dyes used in the food industry. In the form of dye, it represents nearly 70% of the world natural dye production and 90% in Brazil. In the present work, annatto seeds were used of the species peruana paulista, which had nearly 2.1% of bixin. The process of dye extraction with ethyl alcohol showed 4% of dye in the form of powder with particle diameter of 28mm. The extraction process did not alter the chemical composition of the dye, which was confirmed by the electronic spectrum of absorption. Dyeings were carried out with different mordents to study the total colour difference as well as the wash fastness properties and friction fastness properties under wet and dry conditions. The samples treated with copper sulphate showed colour difference but at the same time showed better fastness results. The samples treated with resin (no formaldehyde) did not alter the colour significantly still better the fastness properties. From the results, it could be stated that the resin could be an alternative for heavy metallic mordents

Extração de metais pesados de efluentes da indústria do petróleo utilizando derivados de óleos vegetais como extratantes

The study of a promising alternative for the treatment of produced water from the oil industry envisaging its reuse was the focus of this work. Millions of liters of water are generated per day, containing heavy metals in low concentrations (< 0,15 mg/L for Pb, <0,04 mg/L for Cd, <0,04 mg/L for Ni). The technology applied to extract these metals from aqueous phase was the solvent extraction and the extratants used were vegetable oils originated from coconut oil. They can be used in natural form or as derivatives, known as MAC - Mixture of Carboxílics Acids. The determination of the heavy metal con¬centrations in a complex matrix was made by using the atomic absorption spectrometry technique (AAS). On the bench tests using synthetics aqueous solutions containing metals, vegetable oils showed no power to extract the metals studied. The extractant MAC was selective for the Pb> Cd> Ni, in the concentration of 8% in the same organic phase. In this condition, the lower efficiency of extraction obtained was 92% for the Pb, 69% for the Cd, in the range of pH ranging from 6 to 8. An experimental planning was conducted for continuous tests. The device used was called MDIF Misturador-Decantador à Inversão de Fases and the aqueous phase was produced water from Pólo Indutrial de Guamaré/RN . No correlation between the studied variables (concentration of metal, concentration of extratant and agitation in the mixing chamer) could be obtained, because of possible factors which occurred as: variation in the composition of the studied sample, phenomena of precipitation and complexation of metals in the reservoir of feed, solubility of extratant

Extração supercrítica do óleo de linhaça: construção do extrator, estudo de parâmetros de processo, avaliação química e antioxidante do produto

The aim of the present study was to extract vegetable oil from brown linseed (Linum usitatissimum L.), determine fatty acid levels, the antioxidant capacity of the extracted oil and perform a rapid economic assessment of the SFE process in the manufacture of oil. The experiments were conducted in a test bench extractor capable of operating with carbon dioxide and co-solvents, obeying 23 factorial planning with central point in triplicate, and having process yield as response variable and pressure, temperature and percentage of cosolvent as independent variables. The yield (mass of extracted oil/mass of raw material used) ranged from 2.2% to 28.8%, with the best results obtained at 250 bar and 50ºC, using 5% (v/v) ethanol co-solvent. The influence of the variables on extraction kinetics and on the composition of the linseed oil obtained was investigated. The extraction kinetic curves obtained were based on different mathematical models available in the literature. The Martínez et al. (2003) model and the Simple Single Plate (SSP) model discussed by Gaspar et al. (2003) represented the experimental data with the lowest mean square errors (MSE). A manufacturing cost of US$17.85/kgoil was estimated for the production of linseed oil using TECANALYSIS software and the Rosa and Meireles method (2005). To establish comparisons with SFE, conventional extraction tests were conducted with a Soxhlet device using petroleum ether. These tests obtained mean yields of 35.2% for an extraction time of 5h. All the oil samples were sterilized and characterized in terms of their composition in fatty acids (FA) using gas chromatography. The main fatty acids detected were: palmitic (C16:0), stearic (C18:0), oleic (C18:1), linoleic (C18:2n-6) and α-linolenic (C18:3n-3). The FA contents obtained with Soxhlet dif ered from those obtained with SFE, with higher percentages of saturated and monounsaturated FA with the Soxhlet technique using petroleum ether. With respect to α-linolenic content (main component of linseed oil) in the samples, SFE performed better than Soxhlet extraction, obtaining percentages between 51.18% and 52.71%, whereas with Soxhlet extraction it was 47.84%. The antioxidant activity of the oil was assessed in the β-carotene/linoleic acid system. The percentages of inhibition of the oxidative process reached 22.11% for the SFE oil, but only 6.09% for commercial oil (cold pressing), suggesting that the SFE technique better preserves the phenolic compounds present in the seed, which are likely responsible for the antioxidant nature of the oil. In vitro tests with the sample displaying the best antioxidant response were conducted in rat liver homogenate to investigate the inhibition of spontaneous lipid peroxidation or autooxidation of biological tissue. Linseed oil proved to be more efficient than fish oil (used as standard) in decreasing lipid peroxidation in the liver tissue of Wistar rats, yielding similar results to those obtained with the use of BHT (synthetic antioxidant). Inhibitory capacity may be explained by the presence of phenolic compounds with antioxidant activity in the linseed oil. The results obtained indicate the need for more detailed studies, given the importance of linseed oil as one of the greatest sources of ω3 among vegetable oils

Utilização de métodos estatísticos multivariados na caracterização do mosaico sucessional em floresta semidecídual

O presente trabalho objetivou verificar a possibilidade da utilização de métodos estatísticos multivariados na caracterização das fases do desenvolvimento do mosaico sucessional de um trecho de floresta estacional semidecidual, através de variáveis estruturais. Foram alocadas parcelas de 10 m x 10 m, em que se procedeu à análise estrutural, ou seja, levantamento fitossociológico acrescido das variáveis Porcentagem de Cobertura (PC), Altura do Dossel (AD) e Cobertura por Lianas (CL). Os métodos estatísticos empregados foram Análise de Componentes Principais e Análise de Agrupamento, mais especificamente Classificação Hierárquica Ascendente. O primeiro componente principal explicou 43,96% da variância total, enquanto o segundo, 25,66%. As variáveis Área Basal (AB), Diâmetro Médio (DM) e Dominância Média (DOM) apresentaram correlações positivas entre si superiores a 0,75, podendo ser DM e DOM consideradas como um grupo de variáveis. As variáveis Número de Indivíduos (NI) e Número de Espécies (NE) apresentaram correlação 0,60, enquanto AD, CL e PC baixas correlações com as demais, indicando a importância da inclusão destas na análise. A classificação hierárquica e a partição dos grupos em quatro foram feitas considerando os dois primeiros eixos fatoriais. Os resultados indicaram dois comportamentos diferenciados: 1) valores baixos para AD e AB: Grupo 1, com valores baixos também para NI, NE e PC (fase de clareira); e Grupo 2, com valores elevados para NI e CL e baixos para DOM e DM (fase de construção); e 2) valores altos para AD e AB: Grupo 3, com valores altos também para NI, NE e PC e valor baixo para CL (fase madura); e Grupo 4, com valores elevados para DOM e DM e mais baixos para CL (fase de degradação). Os métodos estatísticos multivariados permitiram caracterizar as fases do desenvolvimento do mosaico sucessional, através das variáveis estruturais. A forma como foram estimadas as variáveis AD, CL e PC, porém, deve ser aprimorada, assim como é preciso incluir variáveis que discriminem melhor cada fase.

Coeficiente do tanque Classe A obtido por diferentes métodos em ambiente protegido e no campo

There are several methods for determining the Class-A pan coefficient (Kp) to estimate the reference evapotranspiration (ETo), which is of great importance to water management in agriculture. Most of these methods take into account the wind speed, relative humidity and the fetch area. This study was done in region of Botucatu, SP, in greenhouse and field in the months of July-August (dry) and September-October (rainy), used the methods of Doorenbos e Pruitt (1977), Cuenca (1989), Snyder (1992), Pereira et al. (1995), Allen et al. (1998) and correlation between ETo determined by Penman-Monteith (EToPM) and evaporation of the Class-A pan (ECA). The EToPM was used as standard for the correlations between the ETo determined by the Class-A pan (EToTCA) obtained by different methods of Kp. The Kp in greenhouse ranged between 0.51 and 0.85, and in the field from 0.33 to 0.85. The methods of Allen et al. (1998) and Snyder (1992) are the most recommended for dry months in greenhouse and rainy months the correlation between the ECA and EToPM e Cuenca (1989). In the field condition, the methods of Allen et al. (1998) and of correlation between the ECA and EToPM for dry months, and for rainy months of Allen et al. (1998) and Cuenca (1989). The method of Allen et al. (1998) was the most efficient, regardless of the environment and of months analyzed. The fixed value of Kp should only be used when it is not possible to determine from its more sophisticated methods.

Estudo da influência de tensoativos em sistemas microemulsionados na extração de gálio e alumínio

Gallium is an important material used in the electronic industry whose demand in the world market is increasing in view of its potential applications. A selective technique is required to allow for the production of the metal, separated from aluminium. Due to the fact that microemulsions constitute an attractive alternative to metal extraction procedures, microemulsified systems have been employed as gallium-selective extraction agents. Two surfactants have been synthesized: sodium 12-N,N-diethylamino-9,10-dihydroxyestearate (AMINE) and saponified coconut oil (SCO), both produced from raw materials readily available in Northeastern Brazil. Also, the commercial extraction agent KELEX-100, conventionally used with the same purpose, has been used in this work for comparison. The optimization of the extraction process with microemulsions was carried out by investigating the influence of some parameters, namely the type of cosurfactant, the cosurfactant/surfactant (C/S) ratio, the pH and concentration of metals in the aqueous phase. Pseudoternary diagrams, which are representative of the microemulsified systems under study, have been constructed in order to establish the boundaries of the regions where the several Winsor systems are formed. An experimental planning methodology (Scheffé Net) has been used to optimize the extraction. The extraction percentage values were as high as 100% for gallium and 99.99% for aluminium for the system with KELEX-100; 96.6% for gallium and 98.8% for aluminium for the system containing AMINE; and 88% for gallium and 85% for aluminium for the system with SCO. The microemulsified system chosen for presenting the best results in gallium extraction was composed by SCO/isoamyl alcohol/kerosene/Bayer licquor with a C/S ratio of 28 and pH of the original aqueous phase of 6.0. The selectivity that has not been observed in the extraction stage was accomplished in the reextraction process using HCl. For the KELEX-100 system, gallium was reextracted at 100% with 6M HCl and aluminium was reextracted at 100% with 0.8M HCl. For the AMINE system, the reextraction percentages were also 100% for both metals, using 6M HCl for gallium and 0.5M HCl for aluminium. On the other hand, the reextraction percentages for the system with SCO were as high as 84% for gallium and 92% for aluminium, with HCl in the same concentrations as those used in the AMINE system. Finally, an optimized system was applied in the gallium extraction process employing a reciprocating perforated-plates extractor. As a result, the metal content was extracted at a recovery rate of 95% for gallium and 97% for aluminium