Hostalen process

Application To produce high-density polyethylene (HDPE) using the stirred-tank, heavy-diluent Hostalen process. 

Description The Hostalen process is a slurry polymerization method with two reactors parallel or in series. Switching from a single reaction to a reaction in cascade enables producing top quality unimodal and bimodal polyethylene (PE) from narrow to broad molecular weight distribution (MWD) with the same catalyst. 

The Hoechst slurry process was improved over the years and has evolved into what is now called the Hostalen process. Hostalen is a slurry-cascade process that is capable of producing a wide range of molecular weight distributions of HOPE. The modern Hostalen process employs 2 continuous stirred tank reactors that can be run in series or in parallel to produce unimodal and bimodal HOPE (11). 

There are several competing hexane slurry processes, but only Basell (Hostalen process) and Equistar-Maruzen still have active licensing activities. Both processes use similar reactor configuration and operating conditions. 

Basell (Hostalen Process) 2 stirred autoclaves in series Hexane 80-85 <8 1-5 (h per reactor)... 

Hostalen/Krupp Udhe Polyethylene Ethylene Hostalen slurry polymerization process uses 2 reactors in parallel or series to produce a broad range of PEs NA NA... 

Fig. 38. Curves fitted to plateau creep data on the basis of the two-process model with no constraint on parameters ( ) Rigidex 50, X = 20 (X) 006.60, X = 20 (A) y-irradiated Rigidex 50, X = 20 (O) H020, >. = 20 (o) Hostalen GUR, solution-spun fibre...

Hoechst (reincorporated in 1952 Farbwerke Hoechst AG produced 1955 from IG Farben after WWn) Hostalen at low pressure using started production of HDPE in Ziegler catalyst. The HDPE had a slurry cascade process high crystallinity, X = 65-85 %,... 

Priority date of Borealis patent for the Advanced Cascade Process (Hostalen ACP) using the Z-N Avant Z-501 or Avant Z-509 catalysts... 

Poly Hi Solidur Plastics India Limited [4] developed products for use on the Indian Railways based on ultra-high molecular weight PE (UHMWPE Hoechst s Hostalen GUR). The base polymer is mixed with patented additives and uses a computer controlled sintering process and sophisticated fabrication methods to produce a material which is claimed to have much higher values for a number of technically important properties such as wear, chemical and water resistance, impact strength and dynamic coefficient of friction. The growth of the market for UHMWPE products is briefly discussed, and the applications targeted by Poly Hi Solidur Plastics are discussed. 

Figure 23.7. Variation of miorohardness along the sample diameter for SCORIM-processed Vestolen A 6016, Hostalen GM 9255 F, and Stamylan HD8621 moldings as calculated from both indentation diagonals after application of load (0) parallel and ( ) perpendicular to the main direction of flow (MDF)...

If Hostalen is properly processed no harmful vapors should be formed. 

Two versions of the slurry process are most frequently applied. In the autoclave or Hoechst process (named after the former company Hoechst that introduced this version of the slurry process) the reaction temperature is 80-90 °C. Typical ethene pressures in the polymerization reactor are 5-10 bar, allowing the application of very large reactors (typically 100 m ). The catalyst compound and the aluminum alkyl activator are premixed in the catalyst preparation vessel with the diluent hexane. This mixture is fed to the polymerization reactor. Figure 6.20.3 shows a schematic view of the process with one polymerization reactor, but cascades of two or more polymerization reactors are also frequently found (allowing additional freedom in achieving specific molecular mass distributions of the PE product - see also picture at the beginning of the section, Hostalen ACP technology). 

High density polyethylene (HOPE) plastics, for example, feature a high level of crystallinity (70-90%), whereas the crystallinity of low density polyethylene (LDPE) lies between 20 and 60%. PE of a normal molecular mass (50,000-300,000) has a low level of viscosity, whereas PE with a very large molecular mass (5,000,000, Hostalen GUR) usually has such a high level of viscosity that it may only be processed using a pressing method. 

Hostalen A slurry process for making high-density polyethylene using a Ziegler catalyst. Two reactors are used, in series or in parallel, which permits the produetion of a variety of molecular weight distributions. Developed and licensed by Basell Polyolefins. In 2005, 33 plants were operating or under construction. Hostalen is also a trade name for the polymer produets. See also next entry. 

Hostalen Advanced Cascade Process (ACP) A process for making polyethylene with mixed molecular weight polymers. Developed by LyondellBasell Industries. Operated in Germany, Poland, and Saudi Arabia in 2013. 

Formic Acid 100 9 Specimen is resistant swelling <3% or weight loss Polystone M Rochling Engineered Plastics <0.5% break elongation not significantly altered 20 30 8 Resistant mechanical properties are not appreciably Hostalen GUR Hoechst Celanese Specimen affected Dumbell type test specimen 50 30 8 70 7 <15% loss in property values little or no chemical Tivar Poly Hi Solidur Specimen Based on attack well-processed or well-fabricated test specimen 122 7... 

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