Inventor · disambiguated record
Erhart K. Drechsel
Also filed as: DRECHSEL ERHART K · DRECHSEL ERHART KARL
15 granted patents·224 citations·filing 1971–1983
94Inventor score
Files withPENNZOIL CO15
Top patents by PatentIndex Score
15 records- 0185US3998935AManufacture of potassium sulfatePENNZOIL CO·Filed 1975·Granted Dec 21, 1976·32 cites·12 claims
- 0284US4268492AProcess for production of potassium sulfate and hydrochloric acidPENNZOIL CO·Filed 1979·Granted May 19, 1981·24 cites·12 claims
- 0382US3956464APreparation of phosphatesPENNZOIL CO·Filed 1971·Granted May 11, 1976·28 cites·24 claims
- 0473US4371512AProduction of alkali metal sulfatesPENNZOIL CO·Filed 1981·Granted Feb 1, 1983·20 cites·12 claims
- 0572US4055626AMethod of producing fluoride-free phosphoric acidPENNZOIL CO·Filed 1976·Granted Oct 25, 1977·14 cites·7 claims
- 0671US4435370APreparation of monocalcium phosphate and/or phosphoric acid from phosphate rockPENNZOIL CO·Filed 1981·Granted Mar 6, 1984·19 cites·10 claims
- 0768US4222990AProduction of fluoride-free phosphatesPENNZOIL CO·Filed 1979·Granted Sep 16, 1980·14 cites·12 claims
- 0864US4393032AProduction of phosphoric acid and additional products from phosphate orePENNZOIL CO·Filed 1982·Granted Jul 12, 1983·15 cites·55 claims
- 0961US4191734AFluoride-free phosphate reactionsPENNZOIL CO·Filed 1978·Granted Mar 4, 1980·11 cites·5 claims
- 1058US4086322AProduction of fluoride-free phosphatesPENNZOIL CO·Filed 1975·Granted Apr 25, 1978·8 cites·12 claims
- 1158US4060586ARecovery of fluorides from gypsumPENNZOIL CO·Filed 1976·Granted Nov 29, 1977·10 cites·8 claims
- 1254US4160657APreparation of monocalcium phosphate and phosphoric acidPENNZOIL CO·Filed 1978·Granted Jul 10, 1979·12 cites·15 claims
- 1353US4328196AProduction of alkali metal products from alkali metal fluosilicatePENNZOIL CO·Filed 1980·Granted May 4, 1982·7 cites·12 claims
- 1447US4479923AProduction of phosphoric acid and additional products from phosphate orePENNZOIL CO·Filed 1983·Granted Oct 30, 1984·7 cites·31 claims
- 1538US4105748AMethod of producing phosphoric acid and potassium dihydrogen phosphate from phosphate rock in the substantial absence of fluorine evolutionPENNZOIL CO·Filed 1977·Granted Aug 8, 1978·3 cites·7 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →