Method of depolymerising phenolic polymers
AssigneeStellenbosch University
InventorsNdumiso Sibanda, Harold Pasch, Helen Pfukwa
Life of this patent
Estimating the term…
Abstract
The invention provides a method for depolymerising a phenolic polymer, the method comprising reacting the phenolic polymer with dimethylsulphoxide (DMSO) and a hydrogen halide. The phenolic polymer may be selected from the group consisting of lignin and derivatives thereof. The hydrogen halide may be HBr. The quantity of hydrogen halide per gram of phenolic polymer may be from 30 mmoles to 70 mmoles. The quantity of DMSO per gram of phenolic polymer may be from 0.1 mole to 1 mole. The reaction may be performed at a temperature of from 100 to 120° C. The reaction may be carried out for between 10 h and 14 h. The product of the reaction may comprise vanillin.
Claims20
A method for depolymerising a phenolic polymer, the method comprising reacting the phenolic polymer with dimethylsulphoxide and a hydrogen halide, wherein the product of the reaction comprises at least one compound selected from monomeric and oligomeric forms of vanillin, syringaldehyde, benzaldehyde, p-hydroxybenzaldehyde, eugenol, phenol, phloroglucinol, and 2,4-dihydroxybenzaldehyde.
A method of producing an aromatic compound from a phenolic polymer, the method comprising reacting the phenolic polymer with dimethylsulphoxide and a hydrogen halide to form a reaction mixture, and isolating the aromatic compound from the reaction mixture, wherein the aromatic compound is selected from monomeric and oligomeric forms of vanillin, syringaldehyde, benzaldehyde, p-hydroxybenzaldehyde, eugenol, phenol, phloroglucinol, and 2,4-dihydroxybenzaldehyde.
A method of producing vanillin from lignin, the method comprising reacting the lignin with dimethylsulphoxide and a hydrogen halide to form a reaction mixture, and isolating vanillin from the reaction mixture.
Dependencies are inferred from the claim text.