P

Inventor

WITT DONALD R

17 patents

Patents

17 patents
US4405501ASep 20, 1983

Aging of chromium-containing gel at high pH

PHILLIPS PETROLEUM CO110 citations96
US4392990AJul 12, 1983

Heating silica gel in inert atmosphere before activation

PHILLIPS PETROLEUM CO65 citations96
US4081407AMar 28, 1978

Catalyst support prepared by alcohol treatment of hydrogels

PHILLIPS PETROLEUM CO76 citations95
US5284811AFeb 8, 1994

Polymerization catalysts and processes

PHILLIPS PETROLEUM CO28 citations92
US4152503AMay 1, 1979

Catalyst support prepared by alcohol treatment of hydrogels

PHILLIPS PETROLEUM CO42 citations92
US3947433AMar 30, 1976

Supported chromium oxide catalyst having mixed adjuvant

PHILLIPS PETROLEUM CO45 citations92
US4436883AMar 13, 1984

Polymerization using a support formed by heating silica gel in inert atmosphere

PHILLIPS PETROLEUM CO24 citations82
US4246139AJan 20, 1981

Silica production

PHILLIPS PETROLEUM CO22 citations82
US4136061AJan 23, 1979

Continuous, multiple zone fluidized bed for particle treater

PHILLIPS PETROLEUM CO26 citations82
US3950316AApr 13, 1976

Catalyst support formed by adding acidic material to silica containing titanium

PHILLIPS PETROLEUM CO25 citations82
US5444132AAug 22, 1995

Controlled addition of alkali or alkaline earth salts to a chromium oxide catalyst

PHILLIPS PETROLEUM CO15 citations74
US5073531ADec 17, 1991

Olefin polymerization catalysts and preparation method

PHILLIPS PETROLEUM CO12 citations73
US4436882AMar 13, 1984

Polymerization process utilizing a catalyst prepared by aging of a chromium-containing gel at high pH

PHILLIPS PETROLEUM CO16 citations73
US4001196AJan 4, 1977

Reactivation of organochromium olefin polymerization catalyst in presence of oxygen

PHILLIPS PETROLEUM CO11 citations73
US3974101AAug 10, 1976

Olefin polymerization catalyst

PHILLIPS PETROLEUM CO16 citations73
US3948806AApr 6, 1976

Large pore silica and polymerization catalyst

PHILLIPS PETROLEUM CO9 citations73
US4009327AFeb 22, 1977

Polymerization of olefins

PHILLIPS PETROLEUM CO4 citations62