Inventor
VON PLESSEN HELMOLD
14 patents
⚠️ This page may combine multiple inventors who share the name “VON PLESSEN HELMOLD”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.
HOECHST AG
13 patentsUS4479924AOct 30, 1984
Process for the separation of heavy metal compounds from phosphoric acid
HOECHST AG31 citations92
US4010240AMar 1, 1977
Process for the regeneration of sulfuric acid
HOECHST AG7 citations72
US3972987AAug 3, 1976
Process for regenerating sulfuric acid
HOECHST AG10 citations72
US4916257AApr 10, 1990
Process for the purification of 2-hydroxynaphthalene-6-carboxylic acid
HOECHST AG6 citations71
US4794204ADec 27, 1988
Process for the removal of dimethyl ether in methyl chloride
HOECHST AG9 citations69
US5464876ANov 7, 1995
Process for the recovery of valuable materials during the work-up of polyvinyl chloride
HOECHST AG8 citations65
US5308600AMay 3, 1994
Process for conditioning waste sulfuric acid
HOECHST AG2 citations60
US4145393AMar 20, 1979
Process for the protection against corrosion of cast iron in boiling concentrated sulfuric acid
HOECHST AG2 citations53
US4032622AJun 28, 1977
Method of concentrating sulfuric acid using a boiler of improved cast iron
HOECHST AG3 citations53
US5047558ASep 10, 1991
Process for the preparation of a dioxane adduct of 2-hydroxynaphthalene-6-carboxylic acid
HOECHST AG0 citations51
US4925959AMay 15, 1990
Dioxane adduct of 2-hydroxynaphthalene-6-carboxylic acid and process for the preparation thereof
HOECHST AG0 citations51
US4150103AApr 17, 1979
Foam prevention during the regeneration of waste sulfuric acid with aromatic nitro compounds
HOECHST AG0 citations50
US4148858AApr 10, 1979
Process for the protection against corrosion of cast iron boilers
HOECHST AG0 citations50