Abstract: Bimetal catalyst for the (co)polymerization of &agr;-olefins comprising a co-catalyst consisting of a hydride or an organometallic compound of an element of groups 1, 2 or 13 of the periodic table, and a solid component consisting of at least 95% by weight of titanium, magnesium, hafnium, aluminum, chlorine and R—COO carboxylate groups, wherein R is an aliphatic, cycloaliphatic or aromatic hydrocarbon, containing from 1 to 30 carbon atoms, wherein at least 80% of the titanium is in oxidation state +3, and at least 1% of said titanium in oxidation state +3 has a tetrahedral coordination geometry. Said catalyst allows the production of olefinic polymers, particular polyethylene, with a high molecular weight by means of solution polymerization processes at temperatures exceeding 200° C.
Type:
Grant
Filed:
January 18, 2002
Date of Patent:
April 20, 2004
Assignee:
Polimeri Europa S.r.l.
Inventors:
Francesco Menconi, Giuseppe Conti, Alberto Zanellato, Angelo Moalli
Abstract: The present invention relates to an integrated process for the preparation in continuous of epoxides which comprises: (a) preparing an alcoholic or hydro-alcoholic solution of hydrogen peroxide in a concentration of over 3% by weight, using a gaseous stream containing hydrogen, oxygen and an inert gas, in the presence of a bimetallic catalyst based on palladium and platinum as active components; (b) putting the alcoholic or hydro-alcoholic solution of hydrogen peroxide obtained in step (a) in contact with an olefin and a buffering agent, in the presence of an epoxidation catalyst suspended in the reaction solvent, in order to obtain a reaction mixture containing the epoxide corresponding to the olefin, water and the alcoholic solvent; (c) treating the alcoholic stream leaving step (b), after separation of the epoxide, in order to eliminate the nitrogenated compounds present; (d) feeding the alcoholic solvent obtained in (c) to step (a).
Type:
Grant
Filed:
June 26, 2002
Date of Patent:
April 1, 2003
Assignee:
Polimeri Europa S.r.l.
Inventors:
Giuseppe Paparatto, Anna Forlin, Giordano De Alberti, Rino D'Aloisio, Paolo Tegon