Abstract: An apparatus and a method to withdraw samples from a polymerization plant using a defined sequence of steps combined with locking devices for valves opened by a single key.

Abstract: An apparatus and a method to withdraw samples from a polymerization plant using a defined sequence of steps combined with locking devices for valves opened by a single key.

Abstract: A process for the polymerization of one or more olefins under solution polymerization conditions to produce a polymeric solution, said process comprising contacting the produced polymeric solution with one or more antioxidant compounds before or concurrently with subjecting the polymeric solution to a devolatilization step to separate the polymer from the unreacted monomers.

Abstract: A process for introducing a catalyst powder into a polymerization reactor comprising: a) metering the catalyst powder by means of a rotary valve comprising a stator, a rotor and sealing means arranged between said stator and said rotor; b) transferring a metered amount of catalyst powder from said rotary valve to a polymerization reactor; the process further comprising the steps of: c) feeding a flushing compound in one or more internal conduits arranged in the rotor of said rotary valve; d) flushing the catalyst powder away from said sealing means.

Abstract: A process for the polymerization of one or more olefins under solution polymerization conditions to produce a polymeric solution, said process comprising contacting the produced polymeric solution with one or more antioxidant compounds before or concurrently with subjecting the polymeric solution to a devolatilization step to separate the polymer from the unreacted monomers.

Abstract: A process for introducing a catalyst powder into a polymerization reactor comprising: a) metering the catalyst powder by means of a rotary valve comprising a stator, a rotor and sealing means arranged between said stator and said rotor; b) transferring a metered amount of catalyst powder from said rotary valve to a polymerization reactor; the process further comprising the steps of: c) feeding a flushing compound in one or more internal conduits arranged in the rotor of said rotary valve; d) flushing the catalyst powder away from said sealing means.

Abstract: A continuous process for minimizing the agglomeration of freshly manufactured polyolefin pellets comprising the steps of: feeding an aqueous stream containing polyolefin pellets to a tower, cooling said polyolefin pellets during their upward flow along said tower by means of a downward flow of a cooling agent having a density higher than said polyolefin, collecting the cooled pellets from the top of said tower after a residence time in the tower comprised between 2 and 20 minutes.

Abstract: Process for the reduction of a hexavalent chromium oxide based catalyst comprising contacting, under mixing conditions, a hexavalent chromium oxide based catalyst, with a molar excess, in respect of the chromium species, of a solid reducing agent and subjecting the mixture to a temperature in the range 30-1000° C. The process is simple, involves low costs and allows to obtain a permanently reduced chromium catalyst that can be disposed without toxicity risks.

Abstract: A continuous process for minimizing the agglomeration of freshly manufactured polyolefin pellets comprising the steps of: feeding an aqueous stream containing polyolefin pellets to a tower, cooling said polyolefin pellets during their upward flow along said tower by means of a downward flow of a cooling agent having a density higher than said polyolefin, collecting the cooled pellets from the top of said tower after a residence time in the tower comprised between 2 and 20 minutes.