Fluorescence spectroscopy for chromophore studies on bleached kraft pulps
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Sirje Liukko
Abstract
Fluorescence techniques are highly sensitive and, since aromatic lignin is the most likely source of natural pulp fluorescence, they are suitable for detailed investigation of residual lignin in bleached pulps. Such investigations are important to our understanding of the bleachability and brightness reversion of pulps. In this study, the effect of bleaching on pulps was evaluated using fluorescence spectra of two softwood kraft pulps bleached in six elemental chlorine-free and totally chlorine-free sequences. Fluorescence spectra were recorded in each bleaching stage using four different instrument settings. In general, pulp fluorescence at excitation wavelengths of 270 and 350 nm increased as bleaching proceeded. Below a certain lignin content, however, pulp fluorescence measured at an excitation wavelength of 430 nm decreased with the residual lignin content. Carbonyl groups have a quenching effect on fluorescence, and the formation of carbonyl groups after oxygen and ozone delignification induced a decrease in pulp fluorescence. The increase in pulp fluorescence after peroxide bleaching stages was due to the removal of carbonyl groups. Reactions of chromophores during brightness reversion also had an effect on pulp fluorescence. These findings demonstrate that fluorescence spectroscopy provides an interesting tool for pulp bleaching studies.
©2007 by Walter de Gruyter Berlin New York
Articles in the same Issue
- Meetings
- Chemical composition of 36 Brazilian Amazon forest wood species
- Characterization of non-cellulosic glucans in Eucalyptus globulus Labill. wood and kraft pulp
- Study of the phenolic compounds formed during pretreatment of sugarcane bagasse by wet oxidation and steam explosion
- Determination of the accessible hydroxyl groups in heat-treated Styrax tonkinensis (Pierre) Craib ex Hartwich wood by hydrogen-deuterium exchange and 2H NMR spectroscopy
- Lignin modification in the initial phase of softwood kraft pulp delignification with polyoxometalates (POMs)
- Synthesis of light-colored rosin glycerol ester
- Studies on fluorescence of cellulosics
- Fluorescence spectroscopy for chromophore studies on bleached kraft pulps
- Influence of surface structure on wetting of coated offset papers
- Fundamental study of the interaction of Ti atoms with spruce surfaces
- Surface analysis of groundwood paper treated by diffuse coplanar surface barrier discharge (DCSBD) type atmospheric plasma in air and in nitrogen
- Ultrastructural aspects of fibre development during the stone groundwood process: New insights into derived pulp properties
- Stabilization of peracetic acid with aspartic acid diethoxy succinate (AES)
- Stabilization of H2O2 in the presence of Fe(II) and Mn(II) impurities under alkaline conditions
- Viscoelastic properties of green wood across the grain measured by harmonic tests in the range 0–95°C: Hardwood vs. softwood and normal wood vs. reaction wood
- Thermoforming of wood veneer composite sheets
- A revised multi-Fickian moisture transport model to describe non-Fickian effects in wood
- Novel experimental approach for longitudinal-radial stiffness characterisation of clear wood by a single test
- Fracture characterisation of yew (Taxus baccata L.) and spruce (Picea abies [L.] Karst.) in the radial-tangential and tangential-radial crack propagation system by a micro wedge splitting test
- Determination of Young's modulus and shear modulus by means of deflection curves for wood beams obtained in static bending tests
- Insecticidal activity of essential oil from Chamaecyparis formosensis Matsum
- Knotwood as a window to the indirect measurement of the decay resistance of Scots pine heartwood
- Field assessment of wood stake decomposition in forest soil
Articles in the same Issue
- Meetings
- Chemical composition of 36 Brazilian Amazon forest wood species
- Characterization of non-cellulosic glucans in Eucalyptus globulus Labill. wood and kraft pulp
- Study of the phenolic compounds formed during pretreatment of sugarcane bagasse by wet oxidation and steam explosion
- Determination of the accessible hydroxyl groups in heat-treated Styrax tonkinensis (Pierre) Craib ex Hartwich wood by hydrogen-deuterium exchange and 2H NMR spectroscopy
- Lignin modification in the initial phase of softwood kraft pulp delignification with polyoxometalates (POMs)
- Synthesis of light-colored rosin glycerol ester
- Studies on fluorescence of cellulosics
- Fluorescence spectroscopy for chromophore studies on bleached kraft pulps
- Influence of surface structure on wetting of coated offset papers
- Fundamental study of the interaction of Ti atoms with spruce surfaces
- Surface analysis of groundwood paper treated by diffuse coplanar surface barrier discharge (DCSBD) type atmospheric plasma in air and in nitrogen
- Ultrastructural aspects of fibre development during the stone groundwood process: New insights into derived pulp properties
- Stabilization of peracetic acid with aspartic acid diethoxy succinate (AES)
- Stabilization of H2O2 in the presence of Fe(II) and Mn(II) impurities under alkaline conditions
- Viscoelastic properties of green wood across the grain measured by harmonic tests in the range 0–95°C: Hardwood vs. softwood and normal wood vs. reaction wood
- Thermoforming of wood veneer composite sheets
- A revised multi-Fickian moisture transport model to describe non-Fickian effects in wood
- Novel experimental approach for longitudinal-radial stiffness characterisation of clear wood by a single test
- Fracture characterisation of yew (Taxus baccata L.) and spruce (Picea abies [L.] Karst.) in the radial-tangential and tangential-radial crack propagation system by a micro wedge splitting test
- Determination of Young's modulus and shear modulus by means of deflection curves for wood beams obtained in static bending tests
- Insecticidal activity of essential oil from Chamaecyparis formosensis Matsum
- Knotwood as a window to the indirect measurement of the decay resistance of Scots pine heartwood
- Field assessment of wood stake decomposition in forest soil
