The invention relates to a system for producing polyolefin. The system comprises a gas phase reactor (1) for polymerizing an olefin to obtain polymerization product. The gas phase reactor (1) comprises a gas distribution plate (11) arranged inside the gas phase reactor (1); a first outlet (12) for continuously withdrawing polymerization product from the gas phase reactor (1) as a first product stream, the first outlet (12) being arranged above the gas distribution plate (11); and a second outlet (13) for continuously withdrawing polymerization product from the gas phase reactor (1) as a second product stream, the second outlet (13) being arranged above the gas distribution plate (11). The system further comprises a first outlet tank (2) in fluid communication with the first outlet (12) via a first passage (22), wherein the first passage (22) comprises a first valve means (221) for controlling the flow of the first product stream in the first passage (22) and wherein the first outlet tank (2) is arranged to receive the first product stream and to concentrate the first product stream; a product receiver tank (3) in fluid communication with the second outlet (13) via a second passage (31), wherein the second passage (31) comprises a second valve means (311) for controlling the flow of the second product stream in the second passage (31), and wherein the product receiver tank (3) is arranged to receive the second product stream; and a control means in communication with the first valve means (221) and the second valve means (311) and arranged to control the operation of the first valve means (221) and the second valve means (311) so that flow in only one of the first passage (22) and the second passage (31) is allowed at a time.

The invention relates also to a process for recovering polymerization product from a gas phase reactor (1). The gas phase reactor (1) is suitable for polymerizing an olefin to obtain polymerization product and comprises a gas distribution plate (11) arranged inside the gas phase reactor (1); a first outlet (12) for continuously withdrawing polymerization product from the gas phase reactor (1), the first outlet (12) being arranged above the gas distribution plate (11); and a second outlet (13) for continuously withdrawing polymerization product from the gas phase reactor (1), the second outlet (13) being arranged above the gas distribut

The invention relates to a system for producing polyolefin. The system comprises a gas phase reactor (1) for polymerizing an olefin to obtain polymerization product. The gas phase reactor (1) comprises a gas distribution plate (11) arranged inside the gas phase reactor (1); a first outlet (12) for continuously withdrawing polymerization product from the gas phase reactor (1) as a first product stream, the first outlet (12) being arranged above the gas distribution plate (11); and a second outlet (13) for continuously withdrawing polymerization product from the gas phase reactor (1) as a second product stream, the second outlet (13) being arranged above the gas distribution plate (11). The system further comprises a first outlet tank (2) in fluid communication with the first outlet (12) via a first passage (22), wherein the first passage (22) comprises a first valve means (221) for controlling the flow of the first product stream in the first passage (22) and wherein the first outlet tank (2) is arranged to receive the first product stream and to concentrate the first product stream; a product receiver tank (3) in fluid communication with the second outlet (13) via a second passage (31), wherein the second passage (31) comprises a second valve means (311) for controlling the flow of the second product stream in the second passage (31), and wherein the product receiver tank (3) is arranged to receive the second product stream; and a control means in communication with the first valve means (221) and the second valve means (311) and arranged to control the operation of the first valve means (221) and the second valve means (311) so that flow in only one of the first passage (22) and the second passage (31) is allowed at a time.

The invention relates also to a process for recovering polymerization product from a gas phase reactor (1). The gas phase reactor (1) is suitable for polymerizing an olefin to obtain polymerization product and comprises a gas distribution plate (11) arranged inside the gas phase reactor (1); a first outlet (12) for continuously withdrawing polymerization product from the gas phase reactor (1), the first outlet (12) being arranged above the gas distribution plate (11); and a second outlet (13) for continuously withdrawing polymerization product from the gas phase reactor (1), the second outlet (13) being arranged above the gas distribut

The present disclosure relates to a Ziegler-Natta catalyst system comprising a pro-catalyst, a co-catalyst and a selectivity control agent. The pro-catalyst comprises a magnesium compound, a titanium compound and a multi-dentate internal donor, wherein the internal donor is tetraethyl 3,3,3′,3′-tetramethyl-2,2′,3,3′-tetrahydro-1,1′-spirobiindane-5,5′,6,6′-tetracarbonate. The present disclosure further relates to a process for polymerization of an olefin using the Ziegler-Natta catalyst system. The Ziegler-Natta catalyst system of the present disclosure shows very high hydrogen response and thus can be used to produce low to high molecular weight polyolefin.

The present disclosure relates to a Ziegler-Natta catalyst system comprising a pro-catalyst, a co-catalyst and a selectivity control agent. The pro-catalyst comprises a magnesium compound, a titanium compound and a multi-dentate internal donor, wherein the internal donor is tetraethyl 3,3,3′,3′-tetramethyl-2,2′,3,3′-tetrahydro-1,1′-spirobiindane-5,5′,6,6′-tetracarbonate. The present disclosure further relates to a process for polymerization of an olefin using the Ziegler-Natta catalyst system. The Ziegler-Natta catalyst system of the present disclosure shows very high hydrogen response and thus can be used to produce low to high molecular weight polyolefin.

An amino-imine metal complex represented by Formula I, its preparation method and an application thereof are provided. The complex is used as a main catalyst in catalysts for olefin polymerization, and can catalyze the polymerization of ethylene at a relatively high temperature to prepare branched polyethylene having high molecular weight.

##STR00001##

An amino-imine metal complex represented by Formula I, its preparation method and an application thereof are provided. The complex is used as a main catalyst in catalysts for olefin polymerization, and can catalyze the polymerization of ethylene at a relatively high temperature to prepare branched polyethylene having high molecular weight.

##STR00001##

The present invention relates to a polyolefin film and to a process for preparing the same. The polyolefin film, specifically, the linear low-density polyethylene film according to an embodiment of the present invention is readily formed and has excellent mechanical strength and excellent heat seal characteristics.

The present invention relates to a polyolefin film and to a process for preparing the same. The polyolefin film, specifically, the linear low-density polyethylene film according to an embodiment of the present invention is readily formed and has excellent mechanical strength and excellent heat seal characteristics.

Provided in one embodiment is a continuous process for converting waste plastic into recycle for polyethylene polymerization. The process comprises selecting waste plastics containing polyethylene and/or polypropylene, and passing the waste plastics through a pyrolysis reactor to thermally crack at least a portion of the polyolefin waste and produce a pyrolyzed effluent. The pyrolyzed effluent is separated into offgas, a pyrolysis oil and optionally pyrolysis wax comprising a naphtha/diesel fraction and heavy fraction, and char. The pyrolysis oil and wax is passed to a refinery FCC feed pretreater unit. A heavy fraction is recovered and sent to a refinery FCC unit, from which a C.sub.3 olefin/paraffin mixture fraction is recovered, which is passed to a steam cracker for ethylene production. In another embodiment, a propane fraction (C.sub.3) is recovered from a propane/propylene splitter and passed to the steam cracker.

Phosphine phosphonate and phenoxyphosphine ligands bearing polyethylene glycol (PEG) chains are used as described herein to produce heterobimetallic catalysts. The ligands can be metallated selectively with palladium or nickel and secondary metal ions to provide well-defined heterobimetallic compounds. These heterobimetallic complexes exhibit accelerated reaction rates and greater thermal stability in olefin polymerization compared to other catalysts.