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Pat Sandra - One of the best experts on this subject based on the ideXlab platform.
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analysis of Jojoba Oil by lc coordination ion spray ms lc cis ms
Journal of Separation Science, 2002Co-Authors: Andrei Medvedovici, K. Lazou, Andre Doosterlinck, Yining Zhao, Pat SandraAbstract:The intact wax esters in Jojoba Oil were analyzed by microbore LC-MS. Neither atmospheric pressure chemical nor electrospray ionization (APCI and ESI) provided ions. Excellent ionization was obtained by adding post column Ag + ions. With this technique, called coordination ion spray MS (CIS-MS), the molecular ion could be unequivocally elucidated and, by applying a collision induced dissociation (CID) voltage of 290 V, the acidic and alcoholic part of the different wax esters could be identified. Ion formation and fragmentation are discussed. Unsaturation in the alcohol or acid chain is not a prerequisite for obtaining [M+Ag] + ions but fragmentation only occurs when the chains are unsaturated.
Jose Aracil - One of the best experts on this subject based on the ideXlab platform.
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Jojoba Oil: A state of the art review and future prospects
Energy Conversion and Management, 2016Co-Authors: Marcos Sanchez, Mercedes Martinez, Mangesh R. Avhad, Jorge M. Marchetti, Jose AracilAbstract:Abstract Jojoba Oil, which is derived from the extraction of Jojoba seed, has a peculiar molecular structure in comparison with the rest of conventional Oils. Jojoba Oil is formed by long monounsaturated esters whereas the rest of the Oils are usually composed by triglycerides. This unconventional structure confers to Jojoba Oil unique properties and characteristics that are very valuable for fine chemical industry and for the production of pharmaceuticals. In addition, Jojoba Oil can be an excellent source of fatty acid alkyl esters or biodiesel after the transesterification process and the purification steps. This review presents general information about the production of Jojoba Oil and its derivatives, its composition, Oil extraction process and the applications of this Oil when it is used directly or after chemical transformation as well as the possible purposes of Jojoba meal after extraction. In addition, this paper contemplates the advantages and disadvantages of the use of homogeneous and heterogeneous catalysts for the Jojoba Oil transesterification as well as different methods to obtain long monounsaturated alcohols, which have pharmaceutical applications, after being separated from biodiesel. The properties of the products derived from the transesterification of Jojoba Oil are broadly discussed. Moreover, this review suggests future research opportunities such as a possible biorefinery using Jojoba Oil as main raw material, supercritical methods and simultaneous extraction/reaction process which are fully discussed.
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fatty acid alkyl esters and monounsaturated alcohols production from Jojoba Oil using short chain alcohols for biorefinery concepts
Industrial Crops and Products, 2015Co-Authors: Noureddin Elboulifi, Marcos Sanchez, Mercedes Martinez, Jose AracilAbstract:Abstract In this work, the Jojoba Oil (JO), was transesterified with four short-chain alcohols to give mixtures of jojobyl alcohols (JA) as main product and fatty acid alkyl esters (FAAE) as co-product in biorefinery concept. As the use of these mixtures as biodiesel have many disadvantages, the separation of JA from the FAAE was carried out. After the separation step, the main properties of transesterified Jojoba Oil (TJO), JA and FAAE were determined. The JA (9-octadecenol, 11-eicosenol, 13-docosenol and 15-tetracosenol), which are obtained through two-step crystallizations have many pharmaceutical applications and a high-added value as main product. From these results, it was found that after the separation of JA from FAAE some properties of the fraction rich in FAAE, has been improved regarding its corresponding TJO. In addition, when other short-chain alcohols instead of methanol were used as transesterification agents, the cold properties and oxidation stability of FAAE were improved, while the kinematic viscosity was increased.
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Jojoba Oil biorefinery using a green catalyst part i simulation of the process
Biofuels Bioproducts and Biorefining, 2015Co-Authors: Marcos Sanchez, J M Marchetti, Mercedes Martinez, Noureddin El Oulifi, Jose AracilAbstract:Abstract: In this paper, the concept of a biorefi nery is focused on the use of Jojoba Oil together with a catalyst produced from waste derived from the fi sh industry to obtain jojobyl alcohols as a main product and fatty acid methyl ester (FAME) as co-product. The overall process is divided into three steps: a trans-esterifi cation step, crystallization step, and a purifi cation step. For the study of this process, two different simulation softwares were used to run the mass and energy balances. In addition, the main properties of transesterifi ed Jojoba Oil, jojobyl alcohols, and FAME were also determined. On one hand, the jojobyl alcohols (11-eicosenol, 13-docosenol, and 15-tetracosenol), which are obtained through two-step crys-tallizations, have many pharmaceutical applications and a high added value as a main product. From these results, it is concluded that the FAME obtained as a co-product during the process is not suitable to be sold as biodiesel, but it might be used in the biorefi nery to produce electricity, making the overall process energy more effi cient. © 2014 Society of Chemical Industry and John Wiley & Sons, LtdKeywords: Jojoba Oil; biorefi nery; transesterifi cation; heterogeneous; biodiesel; methanolysis
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kinetics of Jojoba Oil methanolysis using a waste from fish industry as catalyst
Chemical Engineering Journal, 2015Co-Authors: Marcos Sanchez, J M Marchetti, Noureddin El Boulifi, Jose Aracil, Mercedes MartinezAbstract:Abstract In this study, the kinetics of the heterogeneous methanolysis of Jojoba Oil using calcined shells of Mytilus Galloprovincialis as catalyst has been studied at different temperatures (45–55–65 °C), methanol:Oil ratios (6:1–9:1–12:1) and catalyst percents (6–8–10%). The main products obtained are the jojobyl alcohols with pharmaceutical activity and Fatty Acid Methyl Ester (FAME) is produced as co-product. The catalyst was synthesized through calcination at 800 °C during 6 h. The catalyst was characterized by BET method, X-ray diffraction analysis (XRD), inductively coupled plasma atomic emission spectrometry (ICP) and transmission electron microscopy (TEM). The catalyst is mainly CaO which is macroporous, it has low porosity and turns to Ca(OH)2 in the course of the reaction. The reaction was performed immediately after the calcination process in order to avoid the poisoning of the catalyst by H2O and CO2. The poisoning of the catalyst and its effect has also been object of this study. In addition, external and internal mass transfer limitations and the effect of different calcination temperatures on the process have been studied. The proposed kinetic mechanism fits a sigmoidal curve because there are mass transfer limitations which control the process at the beginning of the reaction whereas the chemical reaction is the limiting step when a critical amount of FAME and jojobyl alcohols are formed. The chosen variables in this kinetic study have been the temperature, the initial catalyst percent and the methanol:Oil ratio. The kinetic study describes the whole methanolysis process accurately.
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optimization of biodiesel production from Jojoba Oil
Process Safety and Environmental Protection, 2007Co-Authors: Abderrahim Bouaid, Mercedes Martinez, L Bajo, Jose AracilAbstract:Abstract The use of fatty acid methyl ester (FAME), produced from agricultural Oils as a fuel in diesel engines has been proposed as an alternative to diesel from fossil resources. Vegetable Oils are produced from numerous Oil seed crops. Of the several renewable sources and yet not widely known, Jojoba Oil appears to be promising scope for cultivation in arid and semi arid areas. The chemical structure of Jojoba Oil allows its use as a constituent in many lubricating Oil formulation. In the present work, the process of synthesis of methyl esters from Jojoba Oil as alternative vegetable Oil, using a basic catalyst, has been developed and optimized by application of the Factorial Design and Response Surface Methodology. According to this study, the maximum yield of esters (83.5%) can be obtained, working at the maximum level of initial concentration of catalyst (1.35%) and a medium level for the operation temperature (25°C). The model has been proven to adequately describe the experimental range studied and allows to scale-up the process.
Andrei Medvedovici - One of the best experts on this subject based on the ideXlab platform.
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analysis of Jojoba Oil by lc coordination ion spray ms lc cis ms
Journal of Separation Science, 2002Co-Authors: Andrei Medvedovici, K. Lazou, Andre Doosterlinck, Yining Zhao, Pat SandraAbstract:The intact wax esters in Jojoba Oil were analyzed by microbore LC-MS. Neither atmospheric pressure chemical nor electrospray ionization (APCI and ESI) provided ions. Excellent ionization was obtained by adding post column Ag + ions. With this technique, called coordination ion spray MS (CIS-MS), the molecular ion could be unequivocally elucidated and, by applying a collision induced dissociation (CID) voltage of 290 V, the acidic and alcoholic part of the different wax esters could be identified. Ion formation and fragmentation are discussed. Unsaturation in the alcohol or acid chain is not a prerequisite for obtaining [M+Ag] + ions but fragmentation only occurs when the chains are unsaturated.
K. Lazou - One of the best experts on this subject based on the ideXlab platform.
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1The Analysis of Jojoba Oil by LC-Coordination Ion Spray-MS (LC-CIS-MS)
2015Co-Authors: K. Lazou, L. De Reu, M. SchelfautAbstract:wax ester composition Summary Liquid chromatography combined with coordination ion spray mass spectroscopy (LC-CIC-MS) was evaluated for the analysis of the wax esters of Jojoba Oil. Excellent ionisation was obtained to elucidate the molecular ion [M+Ag]+ of the wax esters and, moreover, by applying collision induced dissociation (CID) at 290 V both the acidic and alcoholic part could be identified. 2
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analysis of Jojoba Oil by lc coordination ion spray ms lc cis ms
Journal of Separation Science, 2002Co-Authors: Andrei Medvedovici, K. Lazou, Andre Doosterlinck, Yining Zhao, Pat SandraAbstract:The intact wax esters in Jojoba Oil were analyzed by microbore LC-MS. Neither atmospheric pressure chemical nor electrospray ionization (APCI and ESI) provided ions. Excellent ionization was obtained by adding post column Ag + ions. With this technique, called coordination ion spray MS (CIS-MS), the molecular ion could be unequivocally elucidated and, by applying a collision induced dissociation (CID) voltage of 290 V, the acidic and alcoholic part of the different wax esters could be identified. Ion formation and fragmentation are discussed. Unsaturation in the alcohol or acid chain is not a prerequisite for obtaining [M+Ag] + ions but fragmentation only occurs when the chains are unsaturated.
Maria A Perillo - One of the best experts on this subject based on the ideXlab platform.
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v shaped molecular configuration of wax esters of Jojoba Oil in a langmuir film model
Langmuir, 2018Co-Authors: Benjamin Caruso, Florencia M Martini, Monica Pickholz, Maria A PerilloAbstract:The aim of the present work was to understand the interfacial properties of a complex mixture of wax esters (WEs) obtained from Jojoba Oil (JO). Previously, on the basis of molecular area measurements, a hairpin structure was proposed as the hypothetical configuration of WEs, allowing their organization as compressible monolayers at the air–water interface. In the present work, we contributed with further experimental evidence by combining surface pressure (π), surface potential (ΔV), and PM-IRRAS measurements of JO monolayers and molecular dynamic simulations (MD) on a modified JO model. WEs were self-assembled in Langmuir films. Compression isotherms exhibited πlift-off at 100 A2/molecule mean molecular area (Alift-off) and a collapse point at πc ≈ 2.2 mN/m and Ac ≈ 77 A2/molecule. The ΔV profile reflected two dipolar reorganizations, with one of them at A > Alift-off due to the release of loosely bound water molecules and another one at Ac < A < Alift-off possibly due to reorientations of a more tightl...
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v shaped molecular configuration of wax esters of Jojoba Oil in a langmuir film model
Langmuir, 2018Co-Authors: Benjamin Caruso, Florencia M Martini, Monica Pickholz, Maria A PerilloAbstract:The aim of the present work was to understand the interfacial properties of a complex mixture of wax esters (WEs) obtained from Jojoba Oil (JO). Previously, on the basis of molecular area measurements, a hairpin structure was proposed as the hypothetical configuration of WEs, allowing their organization as compressible monolayers at the air-water interface. In the present work, we contributed with further experimental evidence by combining surface pressure (π), surface potential (Δ V), and PM-IRRAS measurements of JO monolayers and molecular dynamic simulations (MD) on a modified JO model. WEs were self-assembled in Langmuir films. Compression isotherms exhibited πlift-off at 100 A2/molecule mean molecular area ( Alift-off) and a collapse point at πc ≈ 2.2 mN/m and Ac ≈ 77 A2/molecule. The Δ V profile reflected two dipolar reorganizations, with one of them at A > Alift-off due to the release of loosely bound water molecules and another one at Ac < A < Alift-off possibly due to reorientations of a more tightly bound water population. This was consistent with the maximal SP value that was calculated according to a model that considered two populations of oriented water and was very close to the experimental value. The orientation of the ester group that was assumed in that calculation was coherent with the PM-IRRAS behavior of the carbonyl group with the C═O oriented toward the water and the C-O oriented parallel to the surface and was in accordance with their orientational angles (∼45 and ∼90°, respectively) determined by MD simulations. Taken together, the present results confirm a V shape rather than a hairpin configuration of WEs at the air-water interface.
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surface behavior of Jojoba Oil alone or in mixtures with soybean Oil
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2005Co-Authors: Maria A Perillo, Damian MaestriAbstract:Abstract In the present work, the behavior of Jojoba Oil (JO), soybean Oil (SBO) and JO/SBO mixtures at the air–water interface was studied. Experiments were performed by applying the Langmuir balance method. Monomolecular layers were prepared on a water subphase, which were subjected to lateral compression in a rectangular trough, using a Wilhelmy plate as a surface pressure transducer. The results showed that JO form stable and reproducible monomolecular layers at the air–water interface. The surface pressure–area isotherms showed an extremely low collapse pressure (πc) of 2.3 mN/m, a mean molecular area of 210 A2/molecule and a compressional modulus at πc of 23 mN/m, characteristic of liquid expanded monolayers. The compression–expansion cycle exhibited an unusual hysteresis, leading to π values higher in the expansion isotherm compared to those in the compression isotherm at the same mean molecular area. This behavior was interpreted as an increase in the hydration level of the polar groups during the lateral compression, which forced it to be immersed in the subphase. This excess hydration free energy, released to the environment during the compression process, was equivalent to ΔΔG = −94 J/molecule. SBO and JO formed non-ideal mixtures, stabilized by attractive interactions at all proportions. The values of surface tension calculated for the water/monolayer interface (γw/m = 60–70 mN/m for JO content between 0 and 100%) as well as the bending energy of this interface (700 kT units for micro-emulsion particles of 20 nm radii) were extremely high compared with those needed to obtain spontaneous emulsification (0.01 mN/m). This indicated that SBO/JO/water micro-emulsion require the addition of surfactants to become thermodynamically stable.
