Consulta: subjectFacets:"Alkaline extraction"
Registros recuperados: 3
Data/hora: 09/06/2024 01:52:24

A New Process for Extracting Alginates from Laminaria digitata: Reactive Extrusion
Provedor de dados: 5
Autores: Vauchel, Peggy; Kaas, Raymond; Arhaliass, Abdellah; Baron, Regis; Legrand, Julien.
Alginates are natural polysaccharides that are extracted from brown seaweeds and widely used for their rheological properties. The main step in the extraction protocol used in the alginate industry is that of alkaline extraction. A batch process is used for this step, which is time-, water-, and reactant-consuming. The possibility of extracting by reactive extrusion was investigated. The reactive extrusion process appeared to be more efficient than the batch process for the alkaline extraction of alginates from Laminaria digitata in several key ways: Time demand is reduced from about an hour to only few minutes, water and reactant requirements are divided by more than a factor 2, extraction yield is 15% higher (relative enhancement), and the rheological...
Tipo: Text
Palavras-chave: Intrinsic viscosity; Reactive extrusion; Laminaria digitata; Alkaline extraction; Alginate.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-6255.pdf

Decrease in dynamic viscosity and average molecular weight of alginate from Laminaria digitata during alkaline extraction
Provedor de dados: 5
Autores: Vauchel, Peggy; Arhaliass, Abdellah; Legrand, Jack; Kaas, Raymond; Baron, Regis.
Alginates are natural polysaccharides that are extracted from brown seaweeds and widely used for their rheological properties. The central step in the extraction protocol used in the alginate industry is the alkaline extraction, which requires several hours. In this study, a significant decrease in alginate dynamic viscosity was observed after 2 h of alkaline treatment. Intrinsic viscosity and average molecular weight of alginates from alkaline extractions 1-4 h in duration were determined, indicating depolymerization of alginates: average molecular weight decreased significantly during the extraction, falling by a factor of 5 between 1 and 4 h of extraction. These results suggested that reducing extraction time could enable preserving the rheological...
Tipo: Text
Palavras-chave: Laminaria digitata; Intrinsic viscosity; Depolymerization; Average molecular weight; Alkaline extraction; Alginate.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4060.pdf

Quantitative differentiation between soil organic carbon and biochar carbon in Aridisol
Provedor de dados: 118
Autores: Lara,Nelson; Figueroa,Leonardo; Carvajal,Fabiola; Zapata,Yubinza; Urbina,Camilo; Escobar,Hugo.
N. Lara, L. Figueroa, F. Carvajal, Y. Zapata, C. Urbina, and H. Escobar. 2013. Quantitative differentiation between soil organic carbon and biochar carbon in Aridisol. Cien. Inv. Agr. 40(2): 387-395. To understand the effect of biochar, identify its presence and quantify its stability in soil, it is necessary to differentiate between the two main sources of carbon. These sources are resident soil organic matter and biochar, which is produced by burning organic matter under low oxygen concentration in a process known as pyrolysis. The present study employs solid-liquid extraction with an alkaline solution, the efficiency of which was improved by a reflux system and quantification using the modified Walkley-Black method, to distinguish the two carbon sources...
Tipo: Journal article
Palavras-chave: Alkaline extraction; Differentiate; Humic acid; Organic carbon.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202013000200013