Hydrogenolysis of lignin in ZnCl2 and KCl as an inorganic molten salt medium
-
Jörn Appelt
,
Anne Gohrbandt
Abstract
Lignin can be converted into monomeric products with the aid of molten salt media. Molten zinc chloride (ZnCl2)/potassium chloride (KCl) mixtures are suitable for this purpose. The application of an eutectic mixture with low melting points leads to similar main products as are obtained by pyrolysis. The hydrogenolysis of an organosolv lignin in molten salts of ZnCl2/KCl was investigated as a function of reaction temperature, residence time, and lignin concentration, and the composition of liquid products and monophenols was analyzed by gas chromatography-mass spectrometry (GC-MS). The yields can be optimized by the proper selection of the reaction temperature. A longer residence time and higher lignin concentrations lead to increased formation of solid residues and gaseous products. The liquid products mainly consist of substituted phenols derived from lignins. Polymeric products are the result of condensation reactions (i.e., the formation of new C-C linkages in the course of secondary reactions).
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Articles in the same Issue
- Frontmatter
- Original Articles
- Study on the residual lignin in Eucalyptus globulus sulphite pulp
- Hydrogenolysis of lignin in ZnCl2 and KCl as an inorganic molten salt medium
- Synthesis of lignin polyols via oxyalkylation with propylene carbonate
- Preparation of water-dispersive poly(3,4-ethylenedioxythiophene) (PEDOT) conductive nanoparticles in lignosulfonic acid solution
- Properties of polyurethane (PUR) films prepared from liquefied wood (LW) and ethylene glycol (EG)
- Dynamic response of earlywood and latewood within annual growth ring structure of Scots pine subjected to changing relative humidity
- One-stage thermo-hydro treatment (THT) of hardwoods: an analysis of form stability after five soaking-drying cycles
- The variation of tangential rheological properties caused by shrinkage anisotropy and moisture content gradient in white birch disks
- Inheritance of basic density and microfibril angle and their variations among full-sib families and their parental clones in Picea glehnii
- Mechanical properties and chemical composition of beech wood exposed for 30 and 120 days to white-rot fungi
- Chemical improvement of surfaces. Part 3: Covalent modification of Scots pine sapwood with substituted benzoates providing resistance to Aureobasidium pullulans staining fungi
- Chemical and ultrastructural changes of ash wood thermally modified using the thermo-vacuum process: I. Histo/cytochemical studies on changes in the structure and lignin chemistry
- Chemical and ultrastructural changes of ash wood thermally modified (TMW) using the thermo-vacuum process: II. Immunocytochemical study of the distribution of noncellulosic polysaccharides
- Revisiting hardboard properties from the fiber sorting point of view
- Effects of acetylation and formalization on the dynamic water vapor sorption behavior of wood
- Immune-regulatory activity of methanolic extract of Acacia confusa heartwood and melanoxetin isolated from the extract
- Stereomicroscopic optical method for the assessment of load transfer patterns across the wood-adhesive bond interphase
Articles in the same Issue
- Frontmatter
- Original Articles
- Study on the residual lignin in Eucalyptus globulus sulphite pulp
- Hydrogenolysis of lignin in ZnCl2 and KCl as an inorganic molten salt medium
- Synthesis of lignin polyols via oxyalkylation with propylene carbonate
- Preparation of water-dispersive poly(3,4-ethylenedioxythiophene) (PEDOT) conductive nanoparticles in lignosulfonic acid solution
- Properties of polyurethane (PUR) films prepared from liquefied wood (LW) and ethylene glycol (EG)
- Dynamic response of earlywood and latewood within annual growth ring structure of Scots pine subjected to changing relative humidity
- One-stage thermo-hydro treatment (THT) of hardwoods: an analysis of form stability after five soaking-drying cycles
- The variation of tangential rheological properties caused by shrinkage anisotropy and moisture content gradient in white birch disks
- Inheritance of basic density and microfibril angle and their variations among full-sib families and their parental clones in Picea glehnii
- Mechanical properties and chemical composition of beech wood exposed for 30 and 120 days to white-rot fungi
- Chemical improvement of surfaces. Part 3: Covalent modification of Scots pine sapwood with substituted benzoates providing resistance to Aureobasidium pullulans staining fungi
- Chemical and ultrastructural changes of ash wood thermally modified using the thermo-vacuum process: I. Histo/cytochemical studies on changes in the structure and lignin chemistry
- Chemical and ultrastructural changes of ash wood thermally modified (TMW) using the thermo-vacuum process: II. Immunocytochemical study of the distribution of noncellulosic polysaccharides
- Revisiting hardboard properties from the fiber sorting point of view
- Effects of acetylation and formalization on the dynamic water vapor sorption behavior of wood
- Immune-regulatory activity of methanolic extract of Acacia confusa heartwood and melanoxetin isolated from the extract
- Stereomicroscopic optical method for the assessment of load transfer patterns across the wood-adhesive bond interphase
