Method of pulping cotton-based raw material
AssigneeLenzing Aktiengesellschaft
InventorsStephan Silbermann, Christian Weilach
Life of this patent
Estimating the term…
Abstract
The present invention relates to a method of pulping cotton-based raw material for producing dissolving pulp. More specifically, the invention relates to a process for producing dissolving pulp under alkaline conditions in combination with a gaseous oxidizing agent. The present invention further relates to dissolving pulp obtainable by pulping cotton-based raw material, in particular dissolving pulp obtainable by the method of the present invention, the use of such dissolving pulp for producing regenerated cellulose molded bodies, and methods of producing lyocell or viscose including such dissolving pulp.
Claims14
A method of pulping a cotton-based raw material for producing dissolving pulp, said method comprising:
- a. an incubation step for generating the dissolving pulp by incubating the cotton-based raw material with an alkaline solution in combination with a gaseous oxidizing agent in a pressurized vessel
- i. at a temperature of about 90-about 185° C.,
- ii. for an incubation time of about 45-about 270 min,
- iii. in the presence of a cellulose-stabilizing additive,
- iv. at a concentration of alkali of about 1-about 35% (w/w) of the cotton-based raw material, and
- v. at an initial gas pressure of about 1-about 21 bar (about 0.1 MPa-about 2.1 MPa), thereby generating the dissolving pulp;
- and
- b. a step of washing the dissolving pulp,
- wherein the cotton-based raw material is a pre- or post-consumer material,
- wherein step a. is the only step for generating the dissolving pulp.
Dependencies are inferred from the claim text.