title: Simultaneous recovery of organic and inorganic content of paper deinking residue through low-temperature microwave-assisted pyrolysis.
abstract: Significant amounts of paper deinking residue (DIR) has been and is still being generated from paper deinking processes, representing both an economic and environmental burden for recycled paper mills. Our research on low-temperature (<200 °C) microwave-assisted (MW-assisted) pyrolysis of DIR allows for simultaneously efficient fast separation and recovery of the organic and inorganic content of DIR at relatively low temperature and within 15 min. Our study is the first highly detailed account of the use low-temperature MW-assisted pyrolysis to effect this change. The obtained liquid and solid products were characterized by a variety of analytical techniques (e.g., attenuated total reflection infrared, gas chromatography-mass spectrometry, liquid-state nuclear magnetic resonance (NMR), X-ray diffraction, solid-state cross-polarization/magic-angle spinning (13)C NMR, and Bloch-decay (13)C NMR). The results reveal that the process efficiently separates the inorganic minerals as microwave residue (mainly calcite and kaolinite) from organic matter, and hence the microwave residue could be reused to produce new paper/cardboard products. The organic fraction bio-oil generated is energy-densified and rich in carbohydrates and is a potential source for valuable aromatic compounds.
authors.affiliation: Green Chemistry Centre of Excellence, Department of Chemistry, University of York , York YO10 5DD, U.K.
authors.forename: Zhanrong
authors.initials: Z
authors.lastname: Zhang
authors.forename: Duncan J
authors.initials: DJ
authors.lastname: Macquarrie
authors.forename: Pedro M
authors.initials: PM
authors.lastname: Aguiar
authors.forename: James H
authors.initials: JH
authors.lastname: Clark
authors.forename: Avtar S
authors.initials: AS
authors.lastname: Matharu
mesh_terms: D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D008872:Microwaves; D009821:Oils / Q000737:chemistry / Q000302:isolation & purification; D010209:Paper; D059027:Recycling; D012037:Refuse Disposal / Q000379:methods; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D009821:Oils