Shell Oil Comapny

Zimmer Aktiengesellschaft

Other

Davy Mckee Aktiengesellschaft

Lurgi Zimmer Gmbh

Klaus Mackensen

Fritz Wilhelm

Kevin Dale Allen

Stefan Deiss

Edward James Denton

James Gao Lee

Thomas Louis De Lellis

Donald R Kelsey

Robert Lawrence Blackbourn

Eckhard Seidel

Hans Reitz

Robert Stephen Tomaskovic

Ferdinand Finkeldei

Helmut Heinze

Rudolf Kaempf

Ulrich Thiele

Walter Wenzel

Juergen Krautstrunk

Disclosed is a process for reducing the self-adhesiveness of polytrimethylene terephthalate pellets, which can be carried out in a continuous or batch manner comprising the steps of:

Process and apparatus for crystallization of polytrimethylene terephthalate (PTT)

Process of producing polytrimethylene terephthalate (PTT) by esterification of terephthalic acid (TPA) with trimethylene glycol (TMG) in the presence of a catalytic, titanium compound, precondensation and polycondensation. The esterification is effected in at least two stages, where in the first stage a molar ratio of TMG to TPA of 1.25 to 2.5, a content of titanium of 0 to 40 ppm, a temperature of 245 to 260&deg; C. as well as a pressure of 1 to 3.5 bar are adjusted. In the at least one subsequent stage a content of titanium is adjusted which is higher than in the initial stage by 35 to 110 ppm. For generating the vacuum in the polycondensation and in the precondensation, there are used vapor jet pumps operated with TMG vapor.

Process for producing polytrimethylene terephthalate (PTT)

Process for generating a vacuum and separating the condensable components of the vapors of melt-phase polycondensation in the production of polycarbonate, where at least one or two vapor jets with a downstream spray condenser are connected to the intake side of the polycondensation reactor to be evacuated, and the motive vapor is diphenyl carbonate vapor, and the spray liquid is liquid diphenyl carbonate.

Process for generating a vacuum in production of polycarbonate

Process for multi-stage generation of a vacuum and condensation and recycling of the vapors of polycondensation in the production of polyester, where the last stage includes a liquid ring pump compressing to atmospheric pressure, a cooler and a degasifier tank. The process also includes at least two preceding stages each using a glycol vapor jet that is operated with superheated glycol vapor at a pressure in the range of 0.8 to 1.0 bar abs. and a downstream glycol spray condenser whose operating conditions are regulated to condense a maximum quantity of glycol and at the same time causing the low-boiling reaction by-products including water to remain in the gas phase.

Process for the multistage generation of vacuum for polyester production

Continuous multistep, economical, energy-saving process for making polybutylene terephthalate in which the butanediol-1,4 used to transesterify dimethyl terephthalate is supplied from the condensed vapors volatilized during the precondensation and polycondensation steps of the process. These vapors, which contain low-soluble esters of terephthalic acid as well as butanediol, are condensed by contact with fresh butanediol, and volatilized butanediol containing the esters is recycled to the initial transesterification stage for reaction with dimethyl terephthalate. No additional butanediol is required for the reaction.

Process for the continuous production of polybutylene terephthalate of

Growing community of inventors

Frankfurt am Main, Germany

Klaus Mackensen