title: Fiber surface characterization of old newsprint pulp deinked by combining hemicellulase with laccase-mediator system.
abstract: Deinking of old newsprint (ONP) by combining hemicellulase with laccase-mediator system (LMS) was investigated, and surface chemical composition and fiber morphology changes during the deinking process were studied by electron spectroscopy for chemical analysis (ESCA), contact angle (CA), attenuated total reflectance fourier transform infrared spectrometry (ATR-FTIR), fiber quality analyzer (FQA), and environmental scanning electronic microscopy (ESEM). Results showed that, compared to the pulp deinked with hemicellulase or LMS individually, effective residual ink concentration (ERIC) was lower for the hemicellulase/LMS-deinked pulp. This indicated that there is a synergistic deinking effect between hemicellulase and LMS. It was found that O/C ratio of the fiber surface increased and the surface coverage of lignin decreased during the hemicellulase/LMS deinking process. The contact angle of the hemicellulase/LMS-deinked pulp was lower than that of pulps deinked with each individual enzyme. ESEM observations showed that more fibrils appeared on the fiber surface due to synergistic treatment.
authors.affiliation: Shandong Key Laboratory of Pulp and Paper Engineering, Shandong Polytechnic University, University Park of Science and Technology, Jinan 250353, China.
authors.forename: Q H
authors.initials: QH
authors.lastname: Xu
authors.forename: Y P
authors.initials: YP
authors.lastname: Wang
authors.forename: M H
authors.initials: MH
authors.lastname: Qin
authors.forename: Y J
authors.initials: YJ
authors.lastname: Fu
authors.forename: Z Q
authors.initials: ZQ
authors.lastname: Li
authors.forename: F S
authors.initials: FS
authors.lastname: Zhang
authors.forename: J H
authors.initials: JH
authors.lastname: Li
mesh_terms: D006026:Glycoside Hydrolases / Q000378:metabolism*; D007281:Ink; D042845:Laccase / Q000378:metabolism*; D008031:Lignin / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D010209:Paper; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties
chemical_list: D008031:Lignin; D042845:Laccase; D006026:Glycoside Hydrolases; C023305:hemicellulase