C22B 3/288
Quaternary ammonium
Official title: {Quaternary ammonium}
C22B3/288 (Quaternary ammonium) appears on 52 US grants and 21 published applications in this corpus.
Search patents in C22B- Granted patents
- 52
- Published applications
- 21
- Assignees
- 36
- Inventors
- 73
- Latest grant
- 21 Apr 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 3 | 0 |
| 1977 | 3 | 0 |
| 1978 | 1 | 0 |
| 1979 | 1 | 0 |
| 1980 | 2 | 0 |
| 1981 | 5 | 0 |
| 1982 | 2 | 0 |
| 1983 | 3 | 0 |
| 1984 | 5 | 0 |
| 1985 | 7 | 0 |
| 1986 | 2 | 0 |
| 1987 | 1 | 0 |
| 1988 | 0 | 0 |
| 1989 | 0 | 0 |
| 1990 | 1 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 1 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 0 | 0 |
| 2001 | 1 | 0 |
| 2002 | 0 | 1 |
| 2003 | 0 | 3 |
| 2004 | 1 | 3 |
| 2005 | 1 | 1 |
| 2006 | 0 | 0 |
| 2007 | 3 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 1 | 0 |
| 2011 | 0 | 1 |
| 2012 | 1 | 0 |
| 2013 | 0 | 1 |
| 2014 | 1 | 0 |
| 2015 | 0 | 1 |
| 2016 | 0 | 0 |
| 2017 | 0 | 0 |
| 2018 | 0 | 0 |
| 2019 | 0 | 1 |
| 2020 | 0 | 1 |
| 2021 | 1 | 2 |
| 2022 | 1 | 1 |
| 2023 | 1 | 2 |
| 2024 | 1 | 1 |
| 2025 | 1 | 2 |
| 2026 | 1 | 0 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Process for removing cyanide from a cyanide-bearing aqueous fluid21 Apr 2026US 12,606,462 B2Commonwealth Scientific and Industrial Research Organisation
- Methods for the purification of molybdenum-99 with phase transfer agents14 Oct 2025US 12,441,626 B2Abilene Christian University
- Enhanced separation of rare earth metals16 Apr 2024US 11,958,754 B2Seren Technologies Limited
- Task-specific ionic liquids for selective separation and recovery of rare earth elements19 Dec 2023US 11,845,670 B2The Curators of the University of Missouri
- Extracting rare earth metal from acidic solution by contacting with ionic liquid composition26 Jul 2022US 11,396,684 B2The Queen's University of Belfast
- Method for recovering lithium from waste lithium ion batteries3 Jul 2025US 2025/0219177 A1Asaka Riken Co., Ltd.
- Methods for the Purification of Molybdenum-99 with Phase Transfer Agents3 Apr 2025US 2025/0109035 A1Abilene Christian University
- Task-specific ionic liquids for selective separation and recovery of rare earth elements7 Mar 2024US 2024/0076195 A1The Curators of the University of Missouri
- Process for removing cyanide from a cyanide-bearing aqueous fluid14 Dec 2023US 2023/0399241 A1Commonwealth Scientific and Industrial Research Organisation
- Separation of rare earth metals23 Feb 2023US 2023/0059863 A1The Queen's University of Belfast
Most cited
By later US patents
- Process for producing electrolytic manganese dioxide from geothermal brines38US 6,682,644 B2MidAmerican Energy Holdings Company · 2004
- Method of purifying tantalum35US 4,673,554 ASumitomo Chemical Company, Limited · 1987
- Refining of noble group metals27US 3,979,207 AMatthey Rustenburg Refiners (Proprietary) Limited · 1976
- Leaching cobalt from spent hydroprocessing catalysts with sulfur dioxide23US 4,432,953 AChevron Research Company · 1984
- Recovering metals from spent hydroprocessing catalysts23US 4,500,495 AChevron Research Company · 1985