Xylanase molecular size, pulp pore-structure and pulp delignification

dc.contributor.author	Maiti, B	en
dc.contributor.author	Whitmire, D	en
dc.date.accessioned	2014-06-06T06:43:16Z
dc.date.available	2014-06-06T06:43:16Z
dc.date.issued	1997	en
dc.identifier.issn	00986445	en
dc.identifier.uri	http://62.217.125.90/xmlui/handle/123456789/1140
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-0031337546&partnerID=40&md5=98755dded84d5ff5cc0e9bd1e054559c	en
dc.subject	Bleaching	en
dc.subject	Cellulase	en
dc.subject	Chlorine	en
dc.subject	Lignin	en
dc.subject	Pulp	en
dc.subject	Xylanase	en
dc.subject.other	Bleaching	en
dc.subject.other	Chlorine	en
dc.subject.other	Enzymes	en
dc.subject.other	Lignin	en
dc.subject.other	Molecular weight	en
dc.subject.other	Porosity	en
dc.subject.other	Cellulase	en
dc.subject.other	Delignification	en
dc.subject.other	Hardwood pulps	en
dc.subject.other	Softwood pulps	en
dc.subject.other	Xylanase	en
dc.subject.other	Kraft pulp	en
dc.title	Xylanase molecular size, pulp pore-structure and pulp delignification	en
heal.type	journalArticle	en
heal.publicationDate	1997	en
heal.abstract	Bleaching kraft pulp with chlorine can result in toxic chlorinated species in bleach plant effluent. Removing lignin from kraft pulp with xylanase reduces chlorine required for bleaching, which, in turn, reduces toxic species in bleach plant effluent. Kraft pulp mills using xylanase pretreatment have reduced chlorine requirement for bleaching by 20 to 25% for hardwood pulp but only 10 to 15% for softwood pulp. The work reported here demonostrates that xylanase molecular size and pulp pore structure determine the amount of lignin that xylanase can remove from pulp. Using softwood pulp, xylanases with molecular weights of 20,000 Da, 39,000 Da, and 67,000 Da removed 48%, 39%, and 30% of lignin respectively. Mild cellulase pre-treatment of softwood pulp increased the apparent median pore size from 37Å to 67Å which enabled xylanase to reduce chlorine requirement for softwood pulp bleaching by 31%. The same process applied to hardwood pulp eliminated 41.8% of chlorine required for bleaching.	en
heal.journalName	Chemical Engineering Communications	en
dc.identifier.volume	162	en
dc.identifier.spage	169	en
dc.identifier.epage	178	en