The present invention provides a novel ligand compound, a transition metal compound and a catalyst composition including the same.

A transition metal-based heterogeneous carbonylation reaction catalyst has an excellent catalytic activity and selectivity in the carbonylation reaction and is easily separated from a product, by crosslinking polymerizing a transition metal-based homogeneous catalyst unit through a Friedel-Craft reaction. The catalyst may be used in a method for preparing lactone. The transition metal-based heterogeneous carbonylation reaction catalyst allows to produce lactone or succinic anhydride with an epoxide compound while showing a high selectivity, and can be applied in industrial very usefully due to easy separation from the product and thus reusing thereof.

The invention relates to a process for preparing an aromatic carbonate, comprising reacting a dialkyl carbonate or an alkyl aryl carbonate with an aryl alcohol or an alkyl aryl carbonate, resulting in an aromatic carbonate which is an alkyl aryl carbonate or a diaryl carbonate, wherein a composition comprising a titanium or zirconium alkoxide or aryloxide, wherein the alkoxy group in the titanium or zirconium alkoxide is a group of formula R-0˜ wherein R is an alkyl group having 1 to 4 carbon atoms and the aryloxy group in the titanium or zirconium aryloxide is a group of formula Ar-0˜ wherein Ar is an aryl group having 6 to 12 carbon atoms, and wherein the composition additionally comprises 0.1 to 50 wt. % of an alcohol, based on the total weight of the composition, is mixed with an alcohol or an organic carbonate, and the mixture thus obtained is contacted with said dialkyl carbonate or alkyl aryl carbonate and aryl alcohol or alkyl aryl carbonate to catalyze the preparation of the aromatic carbonate. Further, the invention relates to a process for making a polycarbonate from the diaryl carbonate thus prepared.

The present invention discloses a homogeneous, single site catalyst of formula (I) and a process for preparation thereof using a ligand. The present invention further discloses a process for preparation of linear polyethylene of high molecular weight and degree of crystallinity by using the homogeneous, single site catalyst of formula I.

##STR00001##

A catalyst and a method for synthesizing cyclic carbonate using the catalyst are provided. The catalyst includes a metal complex shown in formula (I): ##STR00001##
wherein R.sup.1, R.sup.2, R.sup.4, and R.sup.5 are independently a C1-C25 alkyl group, a C1-C25 alkoxy group, a C3-C8 cycloalkyl group, a C6-C25 aryl group, a C6-C25 aryloxy group, a C7-C25 aralkyl group, a C7-C25 aralkoxy group, or halogen; R.sup.3 is hydrogen, a C1-C25 alkyl group, a C3-C8 cycloalkyl group, a C6-C25 aryl group, a C6-C25 aryloxy group, a C7-C25 aralkyl group, or a C7-C25 aralkoxy group; M is Sn or Ti; X is Cl, Br, I, or OAc; and L represents ether or furan.

The present application is directed to a method for the conversion of nitrous acid to dinitrogen gas. In particular, the present application relates to a method for the conversion of nitrous acid to dinitrogen gas by contacting the nitrous acid with an amine-functionalized metal organic framework.

A method consisting in depositing coating of a semiconductor such as TiO.sub.2 on the surface of a substrate of activated carbon in the form of grain or powder that acts by an advanced oxidation-reduction mechanism in environmental decontamination processes, by way of a heterogeneous electrocatalysis system applying an electrical potential having a magnitude equal to or greater than that of the bandgap energy of the semiconductor, which is 3.2 eV in the case of anatase TiO.sub.2, such that an electron rises from the valence band to the conduction band, leaving in its place holes, h+, with enough oxidative capacity to be able to oxidise H.sub.2O and form OH radicals.

Novel catalytic compositions are disclosed comprising novel unsymmetrical metallocene catalytic compounds. Also disclosed are uses of such catalytic compositions in olefin polymerisation reactions, as well as processes of polymerising olefins. When compared with the prior art compositions, the catalytic compositions of the invention are markedly more active in the polymerisation of olefins.

A method for making organo-metal material involves providing a metal ion source in a medium that removes metal ions from the source and forms 1D metal-containing coordination polymers that self-assemble and precipitate as at least one of a 2D and 3D coordination polymer material that can be thermally treated to produce a porous metal oxide material.

A renewable biofuel based on a highly efficient batch catalysis methodology for conversion of 1-butene to a new class of potential jet fuel blends. By tuning the catalyst and then using the dimer produced, the carbon use is about 95% or greater. This latter point will be particularly important in the future, where the source of raw materials (i.e., biomass/biofeedstock) is limited.