D21C 3/20
Pulping cellulose-containing materials: with organic solvents or in solvent environment
Official title: with organic solvents {or in solvent environment}
D21C3/20 (Pulping cellulose-containing materials: with organic solvents or in solvent environment) appears on 182 US grants and 251 published applications in this corpus.
Search patents in D21C- Granted patents
- 182
- Published applications
- 251
- Assignees
- 141
- Inventors
- 466
- Latest grant
- 4 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 2 | 0 |
| 1977 | 1 | 0 |
| 1978 | 1 | 0 |
| 1979 | 1 | 0 |
| 1980 | 0 | 0 |
| 1981 | 0 | 0 |
| 1982 | 1 | 0 |
| 1983 | 1 | 0 |
| 1984 | 1 | 0 |
| 1985 | 2 | 0 |
| 1986 | 2 | 0 |
| 1987 | 0 | 0 |
| 1988 | 3 | 0 |
| 1989 | 0 | 0 |
| 1990 | 3 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 1 | 0 |
| 1994 | 1 | 0 |
| 1995 | 2 | 0 |
| 1996 | 0 | 0 |
| 1997 | 2 | 0 |
| 1998 | 2 | 0 |
| 1999 | 3 | 0 |
| 2000 | 0 | 0 |
| 2001 | 2 | 0 |
| 2002 | 0 | 0 |
| 2003 | 1 | 0 |
| 2004 | 0 | 4 |
| 2005 | 1 | 0 |
| 2006 | 2 | 1 |
| 2007 | 0 | 4 |
| 2008 | 1 | 3 |
| 2009 | 0 | 6 |
| 2010 | 3 | 12 |
| 2011 | 7 | 8 |
| 2012 | 6 | 11 |
| 2013 | 7 | 13 |
| 2014 | 9 | 28 |
| 2015 | 13 | 16 |
| 2016 | 9 | 25 |
| 2017 | 9 | 10 |
| 2018 | 7 | 12 |
| 2019 | 8 | 13 |
| 2020 | 5 | 6 |
| 2021 | 14 | 20 |
| 2022 | 7 | 23 |
| 2023 | 8 | 8 |
| 2024 | 14 | 12 |
| 2025 | 15 | 13 |
| 2026 | 5 | 3 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Processes for fractionation of biomass4 Aug 2026US 12,698,590 B2The Board of Trustees of The University of Alabama
- Methods for lignin extraction16 Jun 2026US 12,655,297 B2Canon Virginia, Inc.
- Process for treatment of biomass for pulping and biorefinery applications19 May 2026US 12,630,975 B2Fuma Labs Private Limited
- High yield cooking method14 Apr 2026US 12,601,114 B2AMPPC Finland Oy
- Quantitative Raman spectroscopy10 Mar 2026US 12,571,737 B2Aalto University Foundation sr
- Method of Preparing High-Strength, High-Toughness, and Recyclable Fiberboard with Bionic Structure3 Sep 2026US 2026/0258602 A1Northeast Forestry University
- Biomass treatment16 Jul 2026US 2026/0201072 A1Bio-Sep, Inc.
- Method for processing black liquor in pulp production12 Feb 2026US 2026/0043196 A1Chung Hwa Pulp Corporation
- Method for preparing pulp with relatively high brightness and high-activity lignin25 Dec 2025US 2025/0389084 A1Qilu University of Technology (Shandong Academy of Sciences)
- Use of in-situ ionic liquid (il) and deep eutectic solvent (des) synthesis using chemically synthesized or biomass-derived ions in the pretreatment of biomass4 Dec 2025US 2025/0369183 A1National Technology & Engineering Solutions of Sandia, LLC
Most cited
By later US patents
- Process of pulping and bleaching fibrous plant material with tert-butyl alcohol and tert-butyl peroxide128US 5,252,183 AABB Lummus Crest Inc. · 1993
- High efficiency organosolv saccharification process109US 4,470,851 A1984
- Process for production of sugars and optionally cellulose and lignin from lignocellulosic raw materials96US 4,520,105 ABau- und Forschungsgesellschaft Thermoform AG · 1985
- Pulping of lignocellulose with aqueous alcohol and alkaline earth metal salt catalyst94US 4,594,130 A1986
- Method of separating lignocellulosic material into lignin, cellulose and dissolved sugars88US 5,730,837 AMidwest Research Institute · 1998