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Primary Separation of Antioxidants (Unsaponifiables) the Wet Biomass Microalgae chlamydomonassp. and Production of the Biodiesel

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Natural Science 2014年第15期6卷 1210-1218页

作者： gisel c.enard díaz Yordanka Reyes cruz Mariana Monteiro Fortes carolina Vieira Viegas René González carliz Nelson c. Furtado donato A. Gomes Aranda Greentec Laboratory School of Chemistry Federal University of Rio de Janeiro Rio de Janeiro Brazil Brazilian center for Physical Researches Rio de Janeiro Brazil

This work studies the saponification which directs the wet biomass of algae chlamydomonas sp. like a previous stage to production of biodiesel. This stage allows the obtainment of fatty acids to produce biodiesel, instead of the gross lipid fraction. In addition of the fatty acids, utilizing the same process one can also obtain the fraction unsaponifiable, these are soluble in apolar solvents and contain mainly carotenoids that can take action as antioxidants and photoprotectors, as they reduce the oxidation of unsaturated fatty acids. The saponification direct and extraction of fatty acids from biomass is faster and reduces the time and cost of operation. The separation of unsaponifiable matter from the biomass humid of microalgae chlamydomonas sp., was held according to the method AOcS (ca 6a-40), using extraction Liquid-liquid with hexane as solvent. Subsequently, phase hydroalcoholic or from soap, containing fatty acids, was acidified by addition of H2SO4 and the fatty acids were recovered by the addition of hexane. After acidulation of the soap, necessary for obtaining of the fatty acids was performed the stage of esterification for obtaining of biodiesel. The operating conditions were: molar ratio fatty acid:methanol (1:10), as catalyst 8% H2SO4 calculated in relation to the mass of fatty acid, 200℃ and reaction time of 90 minutes. The content of methyl esters was 96.8% determined by gas chromatography according to standard EN14103. The quality of biodiesel produced from wet biomass of chlamydomonas sp. is according to the specification established by standard EN 14214 and RANP No. 14. For the identification of the composition the unsaponifiable fraction was used the method of High Performance Liquid chromatography (HPLc). The composition of the material unsaponifiable found was of: carotenoids total (0.76%);Lutein (0.45%);Zeaxanthin (0.07%);α-carotene (0.05%);β-carotene (0.11%);13 cisβ-carotene (0.05%) and 9-cisβ-carotene (0.03%).

关键词： Biodiesel Unsaponifiables Esterification

cultivation of Microalgae Monoraphidiumsp., in the Plant Pilot the Grand Valle Bio Energy, for Biodiesel Production

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Natural Science 2015年第7期7卷 370-378页

作者： gisel c.enard díaz Yordanka Reyes cruz René González carliz Rosa c. Vitorino de Paula donato A. Gomes Aranda Marcellus A. G. dario Gustavo Saraiva Marass Nelson c. Furtado Grand Valle Bio Energy Ltda. Rio de Janeiro Brazil Greentec Laboratory School of Chemistry Federal University of Rio de Janeiro Rio de Janeiro Brazil Brazilian center for Physical Researches Rio de Janeiro Brazil

At present, Brazil imports approximately 11 billion liters/year of diesel. With the interruption of the works in the new Petrobras refineries, the projection is that by 2025 this volume will increase to 24.2 billion liters of diesel/year. In this sense, the biodiesel factory Grand Valle Bio Energy Ltda., located in the state of Rio de Janeiro, in conjunction with the FAPERJ makes some investments in technology development for the cultivation and use of microalgae as an alternative raw material in the production of biodiesel. Based on arguments previously said, this work presents the results of the microalgae cultivation Monoraphidium sp. in photobioreactors the pilot plant of the company. The installation with an area of 120 m2 is included with 2 open photobioreactors of type falling film (20 m × 1 m), with a cascade of 18mm and capacity of 4000 L. The lineage cultivated is selected from previous ecophysiological studies that are identified as promising for biodiesel production by having a high potential for the production of lipids. This lineage is maintained at collection of the stock of cultures Laboratory of Green Technologies of the School of chemistry/ UFRJ. The cultivation was performed in means ASM-1 (Gorham et al., 1964), initial pH 8.0, with aeration and circulation average of 8 hours a day during 19 days. The culture was started with an inoculum of 1 × 107 cel/ml. The lipid production was determined in two phases of growth: on day 4 (exponential phase) and 15 day (stationary phase). For the determination and quantification of lipid content, two different methods were assessed for a sample of biomass, submitted to the same processes the separation and drying. The results showed the methodology of Bligh & dyer with modifications as the most efficient in extracting lipids. The total lipid content of the biomass Monoraphidium sp. was 30.58%. The growth rate varied between 0.74 ± 0.01 and 0.68 ± 0.02.

关键词： cultivation Photobioreactors Microalgae Biodiesel

Quantitative extraction of chromium Ⅵ and Ⅲ from tanned leather: a comparative study of pretreatment methods

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Journal of Leather Science and Engineering 2021年第1期3卷 337-349页

作者： Monica gisel Arellano‑Sanchez christine devouge‑Boyer Marie Hubert‑Roux carlos Afonso Melanie Mignot UNIROUEN COBRA UMR CNRS 6014INSANormandie UniversityAvenue de l’Universite76800 Saint‑Etienne‑du‑RouvrayFrance UNIROUEN COBRAUMR CNRS 6014IRCOFNormandie University76821 Mont‑Saint‑Aignan CedexFrance

In this study,seven pretreatment methods for chromium speciation in tanned leather were evaluated:acidic miner‑alization,ethylenediaminetetraacetic acid(EdTA)extraction,diethylenetriaminepentaacetic acid(dTPA)extraction,alkaline extraction(NH 4 OH),ammonium nitrate extraction(NH 4 NO 3),water extraction,and phosphate buffer extrac‑*** mineralization permitted the decomposition of the organic matter and ensured the complete digestion of leathers,giving access to the total content of chromium in each sample using inductively coupled plasma‑atomic emission spectrometry(IcP‑AES).From all the extractant media tested,EdTA proved to be the most efficient,allowing the extraction of cr(VI)and cr(III)as a cr(III)‑EdTA complex,*** validation is presented for EdTA extraction and direct *** the EdTA extraction,method detection limit(MdL)and method quantifica‑tion limit(MQL)for total cr in leather were 3.4 ppb and 11.2 ppb(µg of total cr per L of extraction solution),respec‑*** to the lack of leather certified reference materials(cRMs)for cr(VI),accuracy was evaluated by spiking leather samples with a cr(VI)*** spike recovery of EdTA microwave assisted extraction ranged from 91.0 to 108.6%.Interday precision was also evaluated and all variation coefficients were below 5%,for both mineralization and EdTA *** article provides an efficient procedure to extract quantitatively chromium from leather,while maintaining the speciation,which can be further followed by ion chromatography‑inductively coupled plasma‑mass spectrometry(Ic‑IcP‑MS).

关键词： Hexavalent chromium Speciation Tanned leather Sample pretreatment EdTA complexation Inductively coupled plasma

Hydroesterification of Nannochloropsis oculatamicroalga’s biomass to biodiesel on Al2O3supported Nb2O5catalyst

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Natural Science 2012年第4期4卷 204-210页

作者： Angel Almarales gisel c.enard Roberto Abdala donato A. Gomes Yordanka Reyes Neyda Om Tapanes Ecology department University of Málaga Málaga Spain GREETEc Laboratory Federal University of Rio de Janeiro Rio de Janeiro Brazil Materials Laboratory West Zone State University Center (UEZO) Rio de Janeiro Brazil

Hydroesterification process has been presented biodiesel production from oil the green microalga Nannochloropsis oculata raw materials. Biodiesel studied in this work is the main product got from the hydroesterification of biomass the Nannochloropsis oculata and was obtained from esterification of fatty acid (product of a hydrolysis reaction) with methanol. It was used as catalyst the niobic acid pure and supported on δ-aluminum. The product was evaluated by gas chromatography and other analyses. The optimum conditions found in the conversion (%) for the hydrolysis reactions of the biomass (92.3%). Better results were observed in the algae concentration 20%, lead at 300?c with 20% of catalyst. For esterification of fatty acids of Nannochloropsis oculata (92.24%), were observed the molar ratio methanol: fat acid 3, lead at 200°c with 20% of catalyst supported.

关键词： Biodiesel Microalgae Hydrolysis Esterification Nannochloropsis oculata

Bio-Oil Extracted of Wet Biomass of the Microalga Monoraphidiumsp. for Production of Renewable Hydrocarbons

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Journal of Power and Energy Engineering 2019年第1期7卷 80-90页

作者： Yordanka R. cruz gisel ch. díaz Viviane de S. Borges Andreina Z. F. Leonett René G. carliz Vinicius Rossa Vitor M. E. S. Silva carolina Vieira Viegas donato A. G. Aranda Luciano B. Oliveira GREETEc Laboratory Federal University of Rio de Janeiro (UFRJ) Rio de Janeiro Brazil GcAT Laboratory Federal University of Uberladia (UFU) Rio de Janeiro Brazil Research company Energetic (EPE) Rio de Janeiro Brazil

Renewable hydrocarbons refer to fuels consisting of hydrocarbons of 10 to 20 carbon atoms, produced from biomass, and free of oxygen. Hydrocracking, hydrodeoxygenation and hydrotreatment processes for the production of renewable hydrocarbons are described in the literature. Microalgae have been targeted in recent years to synthesize biomass that can be used in the production of biofuels, such as renewable hydrocarbons, biodiesel or ethanol second generation. In this context the lineage Monoraphidium sp. was selected from previous ecophysiological studies and its potential to produce lipids to develop this research related with the extraction of the bio-oil of the wet biomass of Monoraphidium sp. through heat treatment. consecutively the bio-oil was used as raw material for the production of hydrocarbons through hydrocracking and hydrodeoxygenation processes (HdO) as: decarbonylation, decarboxylation, dehydratation, with in situ production of hydrogen from liquid-phase reforming of glycerol. The reactions were carried out under two different temperature conditions, 350°c and 300°c, respectively, for 1 h and using ruthenium alumina catalyst (Ru/Al2O3). The results showed the bio-oil processing route at a temperature of 350°c promising for the production of hydrocarbons achieving a conversion of 81.54%.

关键词： Renewable Hydrocarbons Hydrotreatment Bio-Oil Monoraphidium sp.

Production of Hydrogen from Aqueous Phase Reforming of Glycerol: Economic Evaluation

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Engineering（科研） 2014年第1期6卷 12-18页

作者： Rodolfo Salazar Pérez Mariana M. V. M. Souza Neyda c. Om Tapanes gisel c.enard diaz donato A. G. Aranda chemical School Federal University of Rio de Janeiro (UFRJ) Rio de Janeiro Brazil State University of Western of Rio de Janeiro (UEZO) Rio de Janeiro Brazil

Glycerol is the main byproduct from the production of biodiesel by transesterification of vegetable oils, and approximately 10% of total biodiesel production volume corresponds to glycerol. The profitability of various chemical processes depends, in part, on the sale of byproducts, which enables a reduction in the production costs and consequently, in the product’s final price. Thus, it is necessary to look for alternatives to solve the problem of glycerol buildup, in order to avoid future environmental impacts and make biodiesel competitive in the growing market of biofuels. In this context, this study’s objective is the development of a low cost and environmental clean technology that allows the conversion of glycerin into a greater value product. In this paper, an economic evaluation of production hydrogen using Aqueous Phase Reforming (APR) was conducted. Firstly, we detailed the technical assumptions in the study. Reactions were performed in batch reformer of 10 liters of capacity, at the temperature of 250℃ and pressure of 38 atm. Finally, a sensitivity analysis was performed. The results from economic evaluation show that APR of glycerol, using nickel catalysts supported on alumina or zirconium oxide, is a promising and competitive technology for hydrogen production.

关键词： Glycerol Hydrogen Aqueous Phase Reforming Economic Analysis

Separation,speciation and quantification of both chromium(Ⅵ)and chromium(Ⅲ)in tanned leather samples:a comparative study and validation of analytical methods

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Collagen and Leather

collagen and Leather 2023年第2期5卷 51-66页

作者： Mónica gisel Arellano-Sánchez Juliette Vievard Lamia Moufarrej christine devouge-Boyer Marie Hubert-Roux carlos Afonso Mélanie Mignot cOBRA UMR cNRS 6014 INSANormandie UniversityUNIROUENAvenue de l'Université76800 Saint-Etienne-du-RouvrayFrance cOBRA UMR CNRS 6014IRCOFNormandie UniversityUNIROUEN76821 Mont-Saint-Aignan CedexFrance

In the present work,a comparative study of analytical methods for the simultaneous and quantitative determination of trivalent and hexavalent chromium is *** the analysis by ion chromatography-inductively coupled plasma-mass spectrometry,two different columns were tested,as well as different mobile phases and different pH of the *** optimized analytical method permitted the separation of cr(Ⅲ)and cr(Ⅵ)using 75 mmol/L NH_(4)NO_(3)pH 3 as chromatographic *** method was validated and applied to real samples,allowing the determination of both species simultaneously,even when there is a huge difference of concentration between cr(Ⅲ)and cr(Ⅵ).Limit of detection and limit of quantification for cr(Ⅲ)were found to be 0.016 and 0.054μg/L(0.3 and 1.1μg/kg),respectively,and for cr(Ⅵ)0.13 and 0.43μg/L(7 and 22μg/kg),*** species interconversions were monitored through the use of chromium isotopic standards,which confirmed that the optimized methodology preserves chromium speciation during extraction and ***-transform ion cyclotron resonance-mass spectrometry permitted the structure elucidation of the complex formed during ethylenediaminetetraacetic acid extraction.

关键词： chromium speciation Tanned leather Interconversions Ion chromatography Inductively coupled plasmamass spectrometry Fourier-transform ion cyclotron resonance mass spectrometry

Hydrolysis—Hydrogenation of soybean oil and tallow

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