title: Antisolvent precipitation of water-soluble hemicelluloses from TMP process water.
abstract: During the thermomechanical pulping (TMP) of spruce, hemicelluloses (mainly galactoglucomannans, GGMs) are released into the process water at relatively low concentrations that are currently impossible to efficiently recover. This paper examines the recovery of hemicelluloses precipitated from TMP process water via solubility reduction by adding antisolvents such as methanol, ethanol, and acetone. The phase separation was monitored by turbidity measurements. Gravimetric analysis, FTIR, GC-MS, UV spectroscopy, and ICP-OES were used to determine the yield, purity, and composition of the precipitates. Gel permeation chromatography and pulsed field-gradient self-diffusion NMR were used to measure the molecular mass distribution of the precipitates. Acetone was found to be the most efficient antisolvent, giving the highest yield at the lowest addition. The contents of lipophilic extractives and lignin impurities were below 0.5% and 1.6%, respectively, and the metal content was approximately 2% in the precipitates obtained with acetone.
authors.affiliation: Fibre Science and Communication Network (FSCN), Mid Sweden University, SE-851 70 Sundsvall, Sweden. Electronic address: dariusz.zasadowski@miun.se.
authors.forename: Dariusz
authors.initials: D
authors.lastname: Zasadowski
authors.affiliation: Fibre Science and Communication Network (FSCN), Mid Sweden University, SE-851 70 Sundsvall, Sweden. Electronic address: jiayi.yang@miun.se.
authors.forename: Jiayi
authors.initials: J
authors.lastname: Yang
authors.affiliation: Fibre Science and Communication Network (FSCN), Mid Sweden University, SE-851 70 Sundsvall, Sweden. Electronic address: hakan.edlund@miun.se.
authors.forename: Håkan
authors.initials: H
authors.lastname: Edlund
authors.affiliation: Fibre Science and Communication Network (FSCN), Mid Sweden University, SE-851 70 Sundsvall, Sweden. Electronic address: magnus.norgren@miun.se.
authors.forename: Magnus
authors.initials: M
authors.lastname: Norgren
mesh_terms: D000431:Ethanol / Q000737:chemistry; D008031:Lignin / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D028222:Picea / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D012995:Solubility; D014867:Water / Q000737:chemistry*
chemical_list: D010936:Plant Extracts; D011134:Polysaccharides; D014867:Water; D000431:Ethanol; C007916:hemicellulose; D008031:Lignin
keywords: Acetone (PubChem CID: 180); Antisolvent precipitation; Arabinose (PubChem CID: 66308); Ethanol (PubChem CID: 702); Flotation; Galactose (PubChem CID: 6036); Glucose (PubChem CID: 79025); Hemicelluloses; Henicosanoic acid (PubChem CID: 16898); Mannose (PubChem CID: 18950); Methanol (PubChem CID: 887); Process water; Recovery; Rhamnose (PubChem CID: 439710); Thermomechanical pulping; Trimethylchlorosilane (PubChem CID: 6397)