http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-1386541-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_e3322844fbe60f4f858359f95cb4351a |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/D21C3-20 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/D21C3-20 |
| filingDate | 1973-03-06-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1975-03-05-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-1386541-A |
| titleOfInvention | Process for obtaining cellulose from lignocellulosic raw materials |
| abstract | 1386541 Obtaining cellulose from lignocellulosic materials SOC DE PROMOTION ET D'EXRLOITATION INDUSTRIELLES DE PROCEDES DE BREVETS S A 6 March 1973 [6 March 1972] 10752/73 Heading D2W A process for obtaining cellulose from lignocellulosic raw material comprises (a) impregnating fragments of the raw material with a solution of a substance capable of reacting with lignin to form a water-soluble derivative thereof, the solvent used having at least one component with a boiling point higher than the heating temperature used in the next step (b); (b) immersing the impregnated fragments in a liquid substantially immiscible with said solvent and heating until lignin has been converted to a water-soluble derivative thereof, said liquid having a boiling point higher than the heating temperature; (c) separating the heated raw material from the liquid, (d) extracting the water-soluble lignin derivative from the separated raw material with an aqueous medium, and (e) separting the resulting cellulosic material from the aqueous extract. The substance capable of reacting with lignin to form a water-soluble derivative may be an alkali or alkaline earth metal salt, or ammonium salt of a weak mineral acid, or acid or acid anhydride, or ester, in free or complex form. Specified substances include sodium phenate, sodium stearate, sodium acetate, sodium anilide, sodium bissulphite, acetone-sodium bisulphite, ammonium thiosulphate, ammonium bisulphite, and calcium bisulphite. The solvent used in step (a) may be a mono-, di-, or tri-ol, a mono- or poly-phenol, water-miscible ether or ester, aniline, diethanolamine, or triethanolamine, or a mixture of two or more thereof, of a mixture of at least one thereof with water. The liquid used in step (b) which is substantially immiscible with the solvent used in step (a) may be a paraffinnic mineral oil, silicone oil, n-butyl acetylricinoleate, n-butyl benzoate, diethylene glycol monolaurate, propiophenone, dibutyl ether, or a mixture thereof. The heat-treated material may be separated from the liquid(s) used in step (c) by simple filtration, and the separated solids may be washed with water to remove the watersoluble lignin derivative and any residual water-soluble reactants, and then with an appropriate solvent to remove residual waterinsoluble liquid used in the heating step. The black liquor containing the water-soluble lignin derivative may be acidified to yield lignin, or treated with clarifying agents or adsorbents to yield a clear liquor which may be reused for impregnating the raw material. The waterinsoluble liquid may be reused in the heating step. |
| priorityDate | 1972-03-06-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 48.