C01B 25/238
Cationic impurities
Official title: Cationic impurities {, e.g. arsenic compounds}
C01B25/238 (Cationic impurities) appears on 67 US grants and 30 published applications in this corpus.
Search patents in C01B- Granted patents
- 67
- Published applications
- 30
- Assignees
- 42
- Inventors
- 140
- Latest grant
- 25 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1977 | 1 | 0 |
| 1978 | 1 | 0 |
| 1979 | 1 | 0 |
| 1980 | 5 | 0 |
| 1981 | 8 | 0 |
| 1982 | 0 | 0 |
| 1983 | 2 | 0 |
| 1984 | 4 | 0 |
| 1985 | 5 | 0 |
| 1986 | 0 | 0 |
| 1987 | 4 | 0 |
| 1988 | 3 | 0 |
| 1989 | 5 | 0 |
| 1990 | 2 | 0 |
| 1991 | 2 | 0 |
| 1992 | 1 | 0 |
| 1993 | 2 | 0 |
| 1994 | 0 | 0 |
| 1995 | 1 | 0 |
| 1996 | 1 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 1 |
| 2005 | 0 | 0 |
| 2006 | 0 | 0 |
| 2007 | 0 | 0 |
| 2008 | 0 | 1 |
| 2009 | 0 | 0 |
| 2010 | 0 | 0 |
| 2011 | 1 | 0 |
| 2012 | 0 | 0 |
| 2013 | 0 | 1 |
| 2014 | 1 | 1 |
| 2015 | 0 | 3 |
| 2016 | 0 | 1 |
| 2017 | 2 | 1 |
| 2018 | 2 | 0 |
| 2019 | 0 | 2 |
| 2020 | 1 | 0 |
| 2021 | 1 | 1 |
| 2022 | 1 | 2 |
| 2023 | 2 | 7 |
| 2024 | 1 | 2 |
| 2025 | 3 | 5 |
| 2026 | 4 | 2 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Process for producing technical grade phosphoric acid from sewage sludge ash25 Aug 2026US 12,715,771 B2Tecnicas Reunidas S. A.
- Process for the removal of heavy metals from a phosphoric acid containing composition using a flocculating agent10 Feb 2026US 12,545,582 B2Yara International Asa
- Process for the removal of heavy metals from a phosphoric acid containing composition10 Feb 2026US 12,545,583 B2Yara International Asa
- Process for the removal of heavy metals from a phosphoric acid containing composition using an ionic polymeric surfactant and use of said surfactant in the precipitation of heavy metals in a phosphoric acid containing composition10 Feb 2026US 12,545,584 B2Yara International Asa
- Method for treating solid hazardous heavy metal-containing compositions30 Dec 2025US 12,508,636 B2Yara International Asa
- Processing Of Phosphate Solutions6 Aug 2026US 2026/0225888 A1Easymining Sweden AB
- Compositions and processes for removing heavy metals from phosphoric acid containing streams9 Jul 2026US 2026/0193083 A1Cytec Industries Inc.
- Method for producing high-purity phosphoric acid through quantum behavior control18 Dec 2025US 2025/0382176 A1Ram Technology Co., Ltd.
- Method for producing phosphoric acid22 May 2025US 2025/0162870 A1
- Method for separating and purifying phosphoric acid and phosphogypsum from wet-process phosphoric acid slurry, and phosphoric acid and phosphogypsum prepared thereby22 May 2025US 2025/0162899 A1Institute of Process Engineering, Chinese Academy of Sciences
Most cited
By later US patents
- Metallic ion removal from phosphoric acid22US 4,136,199 AOccidental Chemical Corporation · 1979
- Uranium recovery from pre-treated phosphoric acid19US 4,243,637 AOccidental Petroleum Corporation · 1981
- Removal of magnesium and aluminum impurities from wet process phosphoric acid18US 4,299,804 AAgrico Chemical Company · 1981
- High capacity folded moving bed ion exchange apparatus and method for treating phosphoric acid17US 4,280,904 AAmerican Petro Mart, Inc. · 1981
- Removal of cationic impurities from inorganic solutions17US 4,861,490 APhosphate Engineering & Construction Co., Inc. · 1989