Method for producing cellulose carbamate
US11584804B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 2019 |
| Grant date | Feb 21, 2023 |
| Priority date | — |
| Expiry date | May 21, 2039 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/141
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method for controlling discharges of nitrogen compounds in the production of cellulose carbamate (CCA). Microcrystalline cellulose is produced from chemical pulp produced at a pulp mill, such that the chemical pulp is subjected to acid hydrolysis at an elevated temperature to form microcrystalline cellulose (MCC) and hydrolysate, and the MCC is reacted with urea to produce cellulose carbamate whereby ammonia is released. The microcrystalline cellulose production and the cellulose carbamate production are integrated into the pulp mill having a flue gas system such that carbon dioxide from the flue gases is reacted with released ammonia to produce urea, which is used in the carbamate production.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.