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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Isomerization and esterification of pinene ...

Reynolds, William Bryan, January 1941 (has links)
Thesis (Ph. D.)--University of Chicago, 1936. / Reproduced from type-written copy. "Private edition, distributed by the University of Chicago libraries, Chicago, Illinois." Includes bibliographical references.
2

Heterogeneously Catalyzed Valorization of Monoterpenes to High Value-Added Chemicals / Uppgradering av monoterpener till specialkemikalier med högt förädlingsvärde via heterogen katalys

Golets, Mikhail January 2014 (has links)
A potential industrial process is profitable only if it is successfully implemented by the continuously developing chemical industry. Throughout last decades heterogeneous catalysis has opened doors to the creation of various know-how products which previously were considered unfeasible. Moreover, the use of heterogeneous catalysts allows improving existing processes to shift towards more ecological and cost efficient practices. In particular, polymer or fuel compounds could be eco-friendly produced from wood extractives, as an alternative to the conventional oil resources. This goal becomes even more attractive in light of the upcoming peak-oil. In the Nordic pulping industry turpentine is widely available as a tonnage by-product. Despite its interesting properties and promising application possibilities this fraction is commonly burned in the recovery boilers for energy. Although the chemical composition of turpentine depends strongly on the specific pulping process, α-pinene is the predominant compound and as such most studied. The general message of this thesis is the successful implementation of the heterogeneous catalysts in one-pot value-added upgrading of crude turpentine and specific terpenes, particularly α-pinene. Concepts allowing the production of fragrances, resins, plastics and pharmaceutical compounds are presented in the current study. Both commercial (Amberlyst 70) and self-prepared (Me/Al-SBA-15 or TiO2) catalysts were studied in several reactions including: acetoxylation, isomerization, dehydroisomerisation and oxidation. Both commercially purified α-pinene and crude thermo-mechanical turpentine were used as raw materials in the catalytic one-pot synthesis of value-added compounds. The experiments were performed in both batch and continuous reactor systems depending on the studied reaction. Successful results were obtained in case of several reactions. As an example, upon acetoxylation of α-pinene valuable fragrances – α-terpinyl and bornyl acetates – were produced with yields of 35 and 40 wt-%, respectively. Furthermore, in the dehydroisomerisation reaction of α-pinene, a yield of around 80 wt-% of an important fragrance, solvent and plastics precursor, ρ-cymene, was obtained. In the last case, thermo-mechanical turpentine was also successfully utilized. Still, some α-pinene oxidation tests leading to α-pinene oxide and verbenone fragrances were also carried out. Upon this study, further oxidation of ρ-cymene lead to the formation of ρ-methyl-acetophenone, a product essential for perfumery, pharmaceutical and pesticide industry as well as a potent polymer precursor. In addition, isomerization reactions were performed. Additionally, the catalytic materials were thoroughly characterized and analyzed.
3

The action of nitrogen trioxide on pinene

Rembert, Ernest Wayne. January 1921 (has links) (PDF)
Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1921. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed May 29, 2009) Includes bibliographical references (p. 17).
4

Understanding and improving microbial biofuel tolerance as a result of efflux pump expression through genetic engineering and mathematical modeling

Turner, William James 01 January 2014 (has links)
Recent advances in synthetic biology have enabled the construction of non-native metabolic pathways for production of next-generation biofuels in microbes. One such biofuel is the jet-fuel precursor α-pinene, which can be processed into high-energy pinene dimers. However, accumulation of toxic biofuels in the growth medium limits the possible fuel yield. Overexpression of transporter proteins such as efflux pumps can increase tolerance to biofuels by pumping them out of the cell, thus improving fuel yields. However, too many efflux pumps can compromise the cell as well, creating a trade-off between biofuel toxicity and pump toxicity. In this work we improve the conditions of this trade-off in order to increase pinene tolerance in E. coli. We do so by constructing strains incorporating multiple efflux pumps from a variety of organisms and then testing them for tolerance in growth assay experiments. Previous research has suggested that certain combinations of efflux pumps can confer additional tolerance compared to the individual pumps themselves. However, the functional form of the combination of the tolerance provided by each pump and the toxicity due to their simultaneous activity is unknown. Using differential equations, we developed a growth model incorporating the trade-offs between toxicity of α-pinene and efflux pump activity to describe the dynamics of bacterial growth under these conditions. By analyzing biofuel toxicity and the effects of each efflux pump independently through a series of experiments and mathematical models, we propose a functional form for their combined effect on growth rate. We model the mean exponential growth rate as a function of pump induction and biofuel concentration and compare these results to experimental data. We also apply this technique to modeling toxicity of ionic liquids, a class of corrosive salts that has emerged as and effective chemical for pretreatment of biofuel production feedstock. We compare a model for a variety of ionic liquid responsive efflux pump controllers to that of an IPTG inducible controller and show agreement with experimental data, supporting the model's utility to test control schemes before conducting experiments. The overall goal of this project is to use modeling to guide design of tolerance mechanisms to improve overall biofuel yield.
5

Solvolysis of cis-pinocarvyl p-bromobenzenesulfonate and related esters

Gruenewald, Larry E. 01 January 1966 (has links)
No description available.
6

Bifiltration of air polluted with alpha-pinene

Isik, Güldem January 2008 (has links)
The main objective of this investigation is to determine the effect of different physical and chemical parameters on the performance of biofilters, treating hydrophobic organic compounds. pinene was used as a model substance. Alpha-pinene is commonly found in wood, and therefore found at wood storage facilities and wood processing industries [1]. In this experiment two biofilter which were in equal size, were used. Both of them were filled with perlite for treating the alpha pinene contaminated air. One of the columns contained perlite partially coated with silicone oil to make the surface of perlite more hydrophobic. The filters were run at 5, 2.5 and 1.5 l min-1 air flow rate. The results showed that the silicone oil amended filter performed better at 2.5 l/min with a maximum removal rate of 20 g / (m3 h) in comparison with 15 g/ (m3 h) for the filter without oil. The efficiency was approximately the same for both filters at 1.5 and 5 l/min (40 compare to 35 g/m3 bed h). The flow rate was then set to 2.5 l/min once more. The results showed that the removal rate had increased to approximately 35 g/ (m3 h) and that the efficiency of both filters was approximately the same. The difference in results between the initial run and the later at 2.5 l/min is probably depending on that the microorganisms had become adapted to the α-pinene and that the microorganism communities developed differently in the two filters. / Syftet med denna studie var att undersöka om en ökning av biofilterytans hydrofobicitet kan förbättra effektiviteten med avseende på nedbrytning av en hydrofob förening såsom -pinen. En hydrofob yta skulle kunna medföra en ökning i adsorption av hydrofoba föroreningar vilket i sin tur skulle kunna öka tillgängligheten hos föroreningarna för mikroorganismerna. Försöken utfördes med hjälp av två biofilter fyllda med perlit. Ett filter fylldes med obehandlad perlit medan det andra filtret fylldes med perlit som blandats med silikonlja. Båda filtren ympades med mikroorganismer som växt på träflis. Dessa mikroorganismer är anpassade för att bryta ner -pinen då denna förening friges i stora mängder från trä. Resultaten visar att filtret innehållande perlit täckt med silikonolja var mer effektivt med avseende på nedbrytning avpinen under den första tiden av studien (de första 30 dagarna). Skillnaden i effektivitet mellan filtren minskade dock betydligt med tiden så att skillnaden inte var signifikant under resten av studien. Prover från vätskefasen från de båda filtren undersöktes i mikroskop. Dessa studier visade att olika mikroorganismer dominerade i de båda filtren. Filtret innehållande oljetäckt perlit dominerades av stavformiga bakterier medan filtret innehållande obehandlad perlit dominerades av kocker. Båda filtren innehöll en blandkultur av kocker och stavar. Dessutom växte svamp i båda filtren. Dessa resultat visar att en förändring av ytans hydrofobicitet inte bara kan leda till en ökad adsorption av förorening utan den kan också leda till att andra mikroorganismer får en dominerande roll i filtret. Den maximala nedbrytningshastigheten låg mellan 35 och 40 g pinen/(m3h) under hela studien förutom de 30 första dagarna oberoende av luftflödeshastighet (1,5 , 2,5 respektive 5 l/min). Den maximala nedbrytningshastigheten under inledningen av försöket var 15 g/(m3 h) för filtret innehållande obehandlad perlit och 20 g/(m3h) för filtret innehållande oljetäckt perlit. Luftflödet var 2,5 l/min under den inledande perioden. Ökningen i nedbrytningshastighet med tiden indikerar att mikroorganismerna anpassade sig till miljön. Den relativt konstanta nedbrytningshastigheten under resten av studien indikerar att det var de biokemiska reaktionerna som var hastighetsbegränsande och att masstransporten inte hade någon dominerande roll med avseende på att begränsa hastigheten.
7

Bifiltration of air polluted with alpha-pinene

Isik, Güldem January 2008 (has links)
<p>The main objective of this investigation is to determine the effect of different physical and chemical parameters on the performance of biofilters, treating hydrophobic organic compounds. pinene was used as a model substance. Alpha-pinene is commonly found in wood, and therefore found at wood storage facilities and wood processing industries [1].</p><p>In this experiment two biofilter which were in equal size, were used. Both of them were filled with perlite for treating the alpha pinene contaminated air. One of the columns contained perlite partially coated with silicone oil to make the surface of perlite more hydrophobic. The filters were run at 5, 2.5 and 1.5 l min-1 air flow rate. The results showed that the silicone oil amended filter performed better at 2.5 l/min with a maximum removal rate of 20 g / (m3 h) in comparison with 15 g/ (m3 h) for the filter without oil. The efficiency was approximately the same for both filters at 1.5 and 5 l/min (40 compare to 35 g/m3 bed h). The flow rate was then set to 2.5 l/min once more. The results showed that the removal rate had increased to approximately 35 g/ (m3 h) and that the efficiency of both filters was approximately the same. The difference in results between the initial run and the later at 2.5 l/min is probably depending on that the microorganisms had become adapted to the α-pinene and that the microorganism communities developed differently in the two filters.</p> / <p>Syftet med denna studie var att undersöka om en ökning av biofilterytans hydrofobicitet kan förbättra effektiviteten med avseende på nedbrytning av en hydrofob förening såsom -pinen. En hydrofob yta skulle kunna medföra en ökning i adsorption av hydrofoba föroreningar vilket i sin tur skulle kunna öka tillgängligheten hos föroreningarna för mikroorganismerna. Försöken utfördes med hjälp av två biofilter fyllda med perlit. Ett filter fylldes med obehandlad perlit medan det andra filtret fylldes med perlit som blandats med silikonlja. Båda filtren ympades med mikroorganismer som växt på träflis. Dessa mikroorganismer är anpassade för att bryta ner -pinen då denna förening friges i stora mängder från trä. Resultaten visar att filtret innehållande perlit täckt med silikonolja var mer effektivt med avseende på nedbrytning avpinen under den första tiden av studien (de första 30 dagarna). Skillnaden i effektivitet mellan filtren minskade dock betydligt med tiden så att skillnaden inte var signifikant under resten av studien. Prover från vätskefasen från de båda filtren undersöktes i mikroskop. Dessa studier visade att olika mikroorganismer dominerade i de båda filtren. Filtret innehållande oljetäckt perlit dominerades av stavformiga bakterier medan filtret innehållande obehandlad perlit dominerades av kocker. Båda filtren innehöll en blandkultur av kocker och stavar. Dessutom växte svamp i båda filtren. Dessa resultat visar att en förändring av ytans hydrofobicitet inte bara kan leda till en ökad adsorption av förorening utan den kan också leda till att andra mikroorganismer får en dominerande roll i filtret. Den maximala nedbrytningshastigheten låg mellan 35 och 40 g pinen/(m3h) under hela studien förutom de 30 första dagarna oberoende av luftflödeshastighet (1,5 , 2,5 respektive 5 l/min). Den maximala nedbrytningshastigheten under inledningen av försöket var 15 g/(m3 h) för filtret innehållande obehandlad perlit och 20 g/(m3h) för filtret innehållande oljetäckt perlit. Luftflödet var 2,5 l/min under den inledande perioden. Ökningen i nedbrytningshastighet med tiden indikerar att mikroorganismerna anpassade sig till miljön. Den relativt konstanta nedbrytningshastigheten under resten av studien indikerar att det var de biokemiska reaktionerna som var hastighetsbegränsande och att masstransporten inte hade någon dominerande roll med avseende på att begränsa hastigheten.</p>
8

The use of new technologies to develop environmentally benign processes acid-catalyzed hydrolysis of pinene in aqueous media /

Chamblee, Theresa S., January 2004 (has links) (PDF)
Thesis (Ph. D.)--School of Chemistry and Biochemistry, Georgia Institute of Technology, 2004. Directed by Charles L. Liotts. / Includes bibliographical references.
9

Solvolysis of cis-pinocarvyl p-bromobenzenesulfonate and related esters

Gruenewald, Larry E., January 1966 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1966. / Includes bibliographical references (p. 74-76).
10

Biotransformations of Turpentine Constituents : Oxygenation and Esterification

Lindmark-Henriksson, Marica January 2003 (has links)
This thesis describes methods to obtain value–addedcompounds from TMP-turpentine obtained from the spruce, Piceaabies. The methodology focuses on biotransformations using twoapproaches: an oxygenation approach (i.e. oxygenation ofterpene hydrocarbons by cell cultures) and an esterificationapproach (i.e. lipase-catalysed transesterification of vinylacetate with terpene alcohols, and a further fractionation ofthe TMP-turpentine). The main constituents of the turpentine, a-pinene, b-pineneand limonene, were subjected to a P. abies suspension culture.Allylic oxidation formed the major products for α-pineneand β-pinene, which were further oxidised to theirrespective aldehyde or ketone. One of the minor products froma-pinene, cis-verbenol, was not only transformed into verbenonebut also isomerised to trans-verbenol. Limonene gavelimonene-(1,2)-epoxide as the major product. Fractionation of monoterpenes is accomplished throughphysical separation methods, chromatography and distillation,and lipase-catalysed transesterification of vinyl acetate withterpene alcohols. The esters of myrtenol and trans-pinocarveolwere separated from the more slowly reacting alcohols such asborneol and carveol by use of a combination of the Mucor mieheilipase and Candida antarctica lipase A as catalysts.Furthermore, the non-reacting tertiary terpene alcohols wereseparated from the reacting alcohols in a single step byCandida antarctica lipase A. Lipase-catalysed (Candida antarctica lipase B andPseudomonas cepacia lipase) transesterification of vinylacetate with sterically hindered secondary alcoholsunexpectedly yielded hemiacetals or hemiacetal esters. Thereaction conditions required to obtain these side products havebeen studied. <b>Keywords:</b>Picea abies, Pinaceae, Essential oilscomposition; Terpene alcohol; Hemiacetal; Hemiacetal ester,TMP-turpentine; Monoterpene; α-Pinene; β-Pinene;Limonene; Verbenol; Pinocarveol; Borneol; Myrtenol; Suspensioncell culture; Biotransformation; Lipase-catalysed; Oxidation;Allylic oxidation; Transesterification; Autoxidation;Separation.

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