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1.
Chimia (Aarau) ; 75(9): 780-787, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526184

RESUMO

CST (Crude Sulfate Turpentine) is an upcycled, biomass raw material derived from pinewood, obtained as a by-product of the Kraft process from the pulp and paper industry. The current article provides an overview of major renewable perfumery ingredients obtained from CST-derived alpha- and beta-pinene to-date and part of the Firmenich manufacturing portfolio, post DRT acquisition.


Assuntos
Perfumes , Pinus , Terebintina
2.
Biomacromolecules ; 13(5): 1652-62, 2012 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-22530612

RESUMO

A series of random copoly(styrene)s has been synthesized via radical polymerization of functionalized anthraquinone (AQ) and ß-O-4 lignin model monomers. The copolymers were designed to have a different number of styrene spacer groups between the AQ and ß-O-4 lignin side chains aiming at investigating the distance effects on AQ/ß-O-4 electron transfer mechanisms. A detailed molecular characterization, including techniques such as size exclusion chromatography, MALDI-TOF mass spectrometry, and (1)H, (13)C, (31)P NMR and UV-vis spectroscopies, afforded quantitative information about the composition of the copolymers as well as the average distribution of the AQ and ß-O-4 groups in the macromolecular structures. TGA and DSC thermal analysis have indicated that the copolymers were thermally stable under regular pulping conditions, revealing the inertness of the styrene polymer backbone in the investigation of electron transfer mechanisms. Alkaline pulping experiments showed that close contact between the redox active side chains in the copolymers was fundamental for an efficient degradation of the ß-O-4 lignin model units, highlighting the importance of electron transfer reactions in the lignin degradation mechanisms catalyzed by AQ. In the absence of glucose, AQ units oxidized phenolic ß-O-4 lignin model parts, mainly by electron transfer leading to vanillin as major product. By contrast, in presence of glucose, anthrahydroquinone units (formed by reduction of AQ) reduced the quinone-methide units (issued by dehydration of phenolic ß-O-4 lignin model part) mainly by electron transfer leading to guaiacol as major product. Both processes were distance dependent.


Assuntos
Álcalis/química , Antraquinonas/química , Lignina/química , Poliestirenos/química , Poliestirenos/síntese química , Modelos Moleculares , Estrutura Molecular , Polimerização , Temperatura
3.
Bioresour Technol ; 102(16): 7608-11, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21664814

RESUMO

The Pd/C-catalysed hydrogenolysis of in-situ and isolated lignins from Pinus radiata wood was investigated to gain a more complete understanding of the factors affecting yield and composition of the hydrogenolysis products. Such hydrogenolysis products could potentially be refined into aromatic feedstock chemicals providing sustainable alternatives to petroleum-derived phenols. Lignins were converted into solvent-soluble oils composed of monomeric, dimeric and oligomeric products in high yields, up to 89% of the original lignin. The main monomer products were dihydroconiferyl alcohol and 4-n-propyl guaiacol. Dimeric and oligomeric compounds constituted 75% of the hydrogenolysis oils and were mainly composed of dihydroconiferyl alcohol and 4-n-propyl guaiacol units linked by ß-5, 5-5, 4-O-5 and ß-1 linkages. Hydrogenolysis of steam exploded wood gave lower yields of lignin hydrogenolysis products compared to unmodified wood due to fewer reactive aryl-ether linkages in the lignin.


Assuntos
Biocombustíveis , Hidrogênio/química , Lignina/química , Pinus/química , Ressonância Magnética Nuclear Biomolecular , Fenóis/química , Pressão , Vapor , Madeira/química
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