C02F 2301/08
Multistage treatments
Official title: Multistage treatments, e.g. repetition of the same process step under different conditions
C02F2301/08 (Multistage treatments) appears on 788 US grants and 1,215 published applications in this corpus.
Search patents in C02F- Granted patents
- 788
- Published applications
- 1,215
- Assignees
- 734
- Inventors
- 2,638
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 2 | 0 |
| 1977 | 1 | 0 |
| 1978 | 3 | 0 |
| 1979 | 1 | 0 |
| 1980 | 1 | 0 |
| 1981 | 2 | 0 |
| 1982 | 1 | 0 |
| 1983 | 3 | 0 |
| 1984 | 2 | 0 |
| 1985 | 2 | 0 |
| 1986 | 0 | 0 |
| 1987 | 2 | 0 |
| 1988 | 0 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 1 | 0 |
| 1992 | 2 | 0 |
| 1993 | 2 | 0 |
| 1994 | 2 | 0 |
| 1995 | 4 | 0 |
| 1996 | 2 | 0 |
| 1997 | 6 | 0 |
| 1998 | 5 | 0 |
| 1999 | 6 | 0 |
| 2000 | 3 | 0 |
| 2001 | 4 | 0 |
| 2002 | 3 | 1 |
| 2003 | 5 | 5 |
| 2004 | 4 | 11 |
| 2005 | 10 | 21 |
| 2006 | 11 | 14 |
| 2007 | 11 | 21 |
| 2008 | 10 | 12 |
| 2009 | 16 | 27 |
| 2010 | 12 | 20 |
| 2011 | 17 | 40 |
| 2012 | 15 | 32 |
| 2013 | 19 | 41 |
| 2014 | 15 | 49 |
| 2015 | 21 | 49 |
| 2016 | 28 | 43 |
| 2017 | 25 | 59 |
| 2018 | 30 | 57 |
| 2019 | 68 | 93 |
| 2020 | 64 | 81 |
| 2021 | 68 | 102 |
| 2022 | 61 | 91 |
| 2023 | 65 | 100 |
| 2024 | 52 | 92 |
| 2025 | 60 | 92 |
| 2026 | 41 | 62 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Hybrid system and method of waste heat utilization-based photovoltaic power generation and seawater desalination6 Oct 2026US 12,752,240 B2Xi' An Jiaotong University
- Intelligent reverse osmosis control22 Sep 2026US 12,741,887 B2Ozono Polaris, S.A. de C.V.
- Membranes with controlled porosity for serial filtration8 Sep 2026US 12,728,389 B2Gradiant Corporation
- Water treatment method and water treatment agent composition8 Sep 2026US 12,728,390 B2Organo Corporation
- Apparatus and method for treating waste water1 Sep 2026US 12,722,993 B2Samsung E&A Co., Ltd.
- Equipment and method for removing a supernatant phase from a body of water in a polluted groundwater8 Oct 2026US 2026/0307123 A1ENI S. p. A.
- Utilization of an ultra-high pressure reverse osmosis membrane system to treat industrial wastewater or a reverse osmosis reject waste stream8 Oct 2026US 2026/0308017 A1Renovo Resources LLC
- Two-sludge water reuse process8 Oct 2026US 2026/0308030 A1
- Method for Treating Phosphorus-Containing Wastewater Produced During Preparation of Sulfonamide Compound8 Oct 2026US 2026/0308035 A1Nanhai Beisha Pharmaceutical Co., Ltd.
- Water treatment apparatus and water treatment method8 Oct 2026US 2026/0308036 A1Meidensha Corporation
Most cited
By later US patents
- Process and apparatus for treatment of fluids, particularly desalinization of aqueous solutions140US 4,636,296 A1987
- Apparatus for treating effluents71US 5,145,256 AEnvironmental Equipment Corporation · 1992
- Method for disinfecting a dense fluid medium in a dense medium plasma reactor69US 6,749,759 B2Wisconsin Alumni Research Foundation · 2004
- Sea water desalination using CO2 gas from combustion exhaust68US 6,180,012 B22001
- Medium treatment using ultraviolet light68US 8,980,178 B2Sensor Electronic Technology, Inc. · 2015