Experimental protocol for biodiesel production with isolation of alkenones as coproducts from commercial Isochrysis algal biomass

© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Journal of Visualized Experiments 112 (2016): e54189, doi:10.3791/54189.The need to replace petroleum fuels with alternatives from renewable and more environmentally sustainable sources is of growing importance. Biomass-derived biofuels have gained considerable attention in this regard, however first generation biofuels from edible crops like corn ethanol or soybean biodiesel have generally fallen out of favor. There is thus great interest in the development of methods for the production of liquid fuels from domestic and superior non-edible sources. Here we describe a detailed procedure for the production of a purified biodiesel from the marine microalgae Isochrysis. Additionally, a unique suite of lipids known as polyunsaturated long-chain alkenones are isolated in parallel as potentially valuable coproducts to offset the cost of biodiesel production. Multi-kilogram quantities of Isochrysis are purchased from two commercial sources, one as a wet paste (80% water) that is first dried prior to processing, and the other a dry milled powder (95% dry). Lipids are extracted with hexanes in a Soxhlet apparatus to produce an algal oil ("hexane algal oil") containing both traditional fats (i.e., triglycerides, 46-60% w/w) and alkenones (16-25% w/w). Saponification of the triglycerides in the algal oil allows for separation of the resulting free fatty acids (FFAs) from alkenone-containing neutral lipids. FFAs are then converted to biodiesel (i.e., fatty acid methyl esters, FAMEs) by acid-catalyzed esterification while alkenones are isolated and purified from the neutral lipids by crystallization. We demonstrate that biodiesel from both commercial Isochrysis biomasses have similar but not identical FAME profiles, characterized by elevated polyunsaturated fatty acid contents (approximately 40% w/w). Yields of biodiesel were consistently higher when starting from the Isochrysis wet paste (12% w/w vs. 7% w/w), which can be traced to lower amounts of hexane algal oil obtained from the powdered Isochrysis product.This work was supported by the National Science Foundation (CHE-1151492), the Northwest Advanced Renewables Alliance (fellowship to J. Wilson-Peltier), and through a private donation from friends of WHOI

Decolorization improves the fuel properties of algal biodiesel from Isochrysis sp.

© The Author(s), 2016. This is the author's version of the work and is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Fuel 179 (2016): 229-234, doi:10.1016/j.fuel.2016.03.061.Results from the comprehensive fuel testing according to American Society for Testing and Materials International (ASTM) standards of an alkenone-free and decolorized biodiesel produced from the industrially grown marine microalgae Isochrysis sp. are presented. Fatty acid methyl ester (FAME) profiles of the non-decolorized and subsequently decolorized biodiesel fuels were nearly identical, yet the fuel properties were remarkably different. Significant positive impacts on the cetane number, kinematic viscosity, and lubricity were observed, indicating a potential deleterious effect of pigments like chlorophylls and pheophytins on these fuel properties. The decolorization process using montmorillonite K10 gave on average 90% mass recovery, and allowed for an otherwise unobtainable cloud point determination. Oxidative stability of the decolorized Isochrysis biodiesel remained well below the minimum prescribed in biodiesel standards due to elevated content of highly polyunsaturated fatty acids, however other values were in the range of those prescribed in the ASTM standards. Overall, decolorization improved the fuel properties of biodiesel from Isochrysis and may provide a path toward improved biodiesel fuels from other algal species.This work was supported by the National Science Foundation (CHE-1151492) and through a private donation from friends of WHOI.2017-03-2

Elektronenmikroskopische Befunde bei einer Affenseuche (Cercopithecus aethiops)

Die elektronenmikroskopischen Befunde von G. Müller und D. Peters, die den Erreger einer Affenseuche (Cercopithecua aethiops) als gebogene Stäbe dargestellt haben, werden bestätigt und erweitert. Es gelang, die ätiologische Bedeutung dieser Formen durch die Kombination von Gewebekultur (menschliche Amnionzellen), Tierversuch (Meerschweinchen) und elektronenmikroskopischem Befund in dieser Reihenfolge zu sichern.Electron microscopial data given by G. Müller and D. Peters, describing the agent of a communicable disease of monkeys (Cercopithecus aethiopa) as curved rods, are confirmed and supplemented in morphology. Furthermore, we succeeded in strengthening the etiological significance of this agent by combining its multiplication in human amnion cells, infection of guinea pigs with the 5th passage of the tissue culture and electron microscopy of this agent in all these steps

Biodiesel from Citrus reticulata (mandarin orange) seed oil, a potential non-food feedstock

Oil extracted from Citrus reticulata (mandarin orange) seeds was investigated as a potential feedstock for the production of biodiesel. The biodiesel fuel was prepared by sodium methoxide-catalyzed transesterification of the oil with methanol. Fuel properties that were determined include cetane number, cloud, pour, and cold filter plugging points, kinematic viscosity, oxidative stability, flash point, sulfur content, ash content, density and acid value. The citrus seed oil methyl esters were found to satisfy both ASTM D6751 and EN 14214 biodiesel standards. The NMR spectra of the methyl esters of C. reticulata seed oil are reported

Virtual testing of advanced composites, cellular materials and biomaterials: A review

This paper documents the emergence of virtual testing frameworks for prediction of the constitutive responses of engineering materials. A detailed study is presented, of the philosophy underpinning virtual testing schemes: highlighting the structure, challenges and opportunities posed by a virtual testing strategy compared with traditional laboratory experiments. The virtual testing process has been discussed from atomistic to macrostructural length scales of analyses. Several implementations of virtual testing frameworks for diverse categories of materials are also presented, with particular emphasis on composites, cellular materials and biomaterials (collectively described as heterogeneous systems, in this context). The robustness of virtual frameworks for prediction of the constitutive behaviour of these materials is discussed. The paper also considers the current thinking on developing virtual laboratories in relation to availability of computational resources as well as the development of multi-scale material model algorithms. In conclusion, the paper highlights the challenges facing developments of future virtual testing frameworks. This review represents a comprehensive documentation of the state of knowledge on virtual testing from microscale to macroscale length scales for heterogeneous materials across constitutive responses from elastic to damage regimes

Kijkjes in de ontwikkelings-geschiedenis ons hoger onderwijs / deur G Knothe

Rede uitgesproken bij gelegenheid van de 4de Jaarvergadering van de Suid-Afrikaanse Akandemie voor Taal, Letteren en Kunst, te Pieter Maritzburg, op 4 Julie, 1913, door Professor Dr. G. Knothe. .Toen de Nederlanders zich in 1652 aan de Kaap de Goede Hoop vestigden, wachtten ze niet lang met het oprichten van scholen. Reeds in 1658 stichtte Kommandeur Van Riebeeck de eerste school ,,voor de Angoolse Comps, slaven en de slavinnen", ten einde hen ,,tot het school off leeren van de cristelijcke gebeden" te gewennen. Het spreekt vanzelf, dat het onderwijs in die eerste jaren slechts van zeer elementaire aard was. Zodra de kinderen de ,,proevstukken in 't lesen, schrijven, cijferen, en huns geloovs articulen" gegeven hadden, werden ze als volleerd beschouwd. Deze toestand van zaken duurde bijna onveranderd voort tot 1714. Dit jaar is belangrijk voor de Geschiedenis van 't onderwijs, niet alleen omdat in dit jaar "den Extraordinaris raad van Nederlands India en gouverneur d'Edele heer Maurits Pasques de Chavonnes en den raad van Cabo de Goede Hoop" het "van hooge nootsaakelijke g'aght hadde, vermits met leetwesen ondervond, dat nog op dat goede werk, in dit gouvernement geen bequame order of regulament gesteld is geworden", een Ordonantie beraamde, "waarna den rector en schoolmeesters in dit gouvernment hun voortaan sullen hebben te reguleeren", maar ook, omdat in dit jaar, door het oprichten van de eerste Latijnse School, de eerste poging gedaan werd om 'n hogere Standaard van onderwijs te bereiken. Tot Rektor van deze inrichting werd benoemd Lambertus Slicher "van Middelburgh", die, zoals hij zelf vertelt, "in 't jaar 1714 met 't schip 't Vaderland Getrouw, in de qualiteyd van adelborst hier zijnde aangekomen" nadat hij "in 't vaderland ruym ses jaaren te Lille het predykampt heeft bedient ..

Biodiesel fuels

The mono-alkyl esters, most commonly the methyl esters, of vegetable oils, animal fats or other materials consisting mainly of triacylglycerols, often referred to as biodiesel, are an alternative to conventional petrodiesel for use in compression-ignition engines. The fatty acid esters that thus comprise biodiesel largely determine many important fuel properties. In turn, the composition of the biodiesel depends on the composition of the parent feedstock because feedstocks with widely varying fatty acid composition can be used for biodiesel production. The use of different feedstocks is also significant under aspects of increasing biodiesel supply and socio-economic issues. In this article, biodiesel production is briefly described, followed by a discussion of biodiesel fuel properties and the influence of varying fatty acid profiles and feedstocks. It is shown that the properties of biodiesel least influenced by minor components can be determined by a straightforward equation in which the properties of the biodiesel fuel are calculated from the amounts of the individual component fatty esters and their properties. Optimizing biodiesel composition is also addressed. © 201

Decarboxylation of Fatty Acids with Triruthenium Dodecacarbonyl: Influence of the Compound Structure and Analysis of the Product Mixtures

Recently, the decarboxylation of oleic acid (9(Z)-octadecenoic acid) catalyzed by triruthenium dodecacarbonyl, Ru3(CO)12, to give a mixture of heptadecenes with concomitant formation of other hydrocarbons, heptadecane and C17 alkylbenzenes, was reported. The product mixture, consisting of about 77% heptadecene isomers, 18% heptadecane, and slightly \u3e4% C17 alkylbenzenes, possesses acceptable diesel fuel properties. This reaction is now applied to other fatty acids of varying chain length and degree of saturation as well as double-bond configuration and position. Acids beyond oleic acid included in the present study are lauric (dodecanoic), myristic (tetradecanoic), palmitic (hexadecanoic), stearic (octadecanoic), petroselinic (6(Z)-octadecenoic), elaidic (9(E)-octadecenoic), asclepic (11(Z)-octadecenoic), and linoleic (9(Z),12(Z)-octadecadienoic) acids. Regardless of the chain length and degree of unsaturation, a similar product mixture was obtained in all cases with a mixture of alkenes predominating. Monounsaturated fatty acids, however, afforded the alkane with one carbon less than the parent fatty acid as the most prominent component in the mixture. Alkylbenzenes with one carbon atom less than the parent fatty acid were also present in all product mixtures. The number of isomeric alkenes and alkylbenzenes depends on the number of carbons in the chain of the parent fatty acid. With linoleic acid as the starting material, the amount of alkane was reduced significantly with alkenes and alkylaromatics enhanced compared to the monounsaturated fatty acids. Two alkenes, 9(E)-tetradecene and 1-hexadecene, were also studied as starting materials. A similar product mixture was observed but with comparatively minor amount of alkane formed and alkene isomers dominating at almost 90%. The double-bond position and configuration in the starting material do not influence the pattern of alkene isomers in the product mixture. The results underscore the multifunctionality of the Ru3(CO)12 catalyst, which promotes a reaction sequence including decarboxylation, isomerization, desaturation, hydrogenation, and cyclization (aromatization) to give a mixture of hydrocarbons simulating petrodiesel fuels. A reaction pathway is proposed to explain the existence of these products, in which alkenes are dehydrogenated to alkadienes and then, under cyclization, to the observed alkylaromatics. The liberated hydrogen can then saturate alkenes to the corresponding alkane