Patent US3677939A successfully refreshed from Google Patents.
US3677939A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the use of vermiculite in waste water renovation
Assignee: JOHN W ICRAUS
•
Filing: 1970-10-30
•
Granted: 1972-07-18
•
Expires: 1990-10-30
Abstract
Abstract VERMICULITE, AFTER HAVING BEEN CHEMICALLY TREATED, HAS ENHANCED ABSORPTIVE AND COAGULATIVE PROPERTIES, AND CAN BE USED TO REMOVE CONTAMINATES OCCURING IN WASTE WATERS BY REMOVING PHOSPHATES FROM THE WASTE WATER. THE TREATMENT CONSISTS OF (1) EXPANDING THE VERMICULITE AND (2) TREATING THE EXPANDED VERMICULITE WITH AN AQUEOUS SOLUTION OF AN INORGANIC SALT, THE CATION OF WHICH IS IN A +2 OR HIGHER VALENCE STATE.
Inventors
- 👤 Arvind S Patil
- 👤 John W Icraus
- 👤 Jacob Block
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:21
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; C; C02; C02F; C02F1/00; C02F1/28; C02F1/281; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/906
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |