Advanced cascade process

Fig. 12 Cascade process with three polymerization reactors in series (advanced cascade process)...

Multiple reactors for controlling MWD of HDPE (in parallel or in cascade with different feeds) have been known in the plastics industry as described in a patent DE 656,469 (1938) or U.S. Patent 2363951 (priority 1937) for PS or PVC production. The Advanced Cascade Process (ACP) with three reactors in cascade is an... 

Hoechst s slurry Hostalenis produced via advanced cascade process (ACP), which uses three CSTR in a cascade, enabling the production of multimodal HDPE and/or LLDPE (with butene) resins in butane. For example, the first CSTR is alimented with C2, the second with C2 and C4, and... 

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

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. 

Only a few years ago it was widely accepted that the cofactor regeneration problem represented a serious obstacle with respect to the commercial viability of enzymatic redox processes. Hopefully it is clear from the preceding discussion that there is no longer a cofactor regeneration problem anymore than there is an enzyme problem . The number of readily available enzymes has increased dramatically in the last decade and advances in in vitro evolution have made it possible to routinely optimize the performance of enzymes. The coupling of enzymes in multi-enzyme cascade processes is an attractive way to regenerate cofactors, shift equilibria towards products and remove intermediate products that cause inhibition. Hence, we expect that multi-enzyme cascade processes will become much more common in the future. 

As highlighted in this chapter, [3,3]-rearrangements of N—N and N—O bond fragments participate in a variety of cascade processes to generate inportant heterocyclic structures. Recent advances in this area have focused primarily on the development of improved general methods for accessing the rearrangement precursors in order to expand the utility of the... 

While the single-loop PID controller is satisfactoiy in many process apphcations, it does not perform well for processes with slow dynamics, time delays, frequent disturbances, or multivariable interactions. We discuss several advanced control methods hereafter that can be implemented via computer control, namely feedforward control, cascade control, time-delay compensation, selective and override control, adaptive control, fuzzy logic control, and statistical process control. 

Thanks are due to Michiel Makkee, who developed the combi-mannitol process in the 1980s at the Delft University of Technology, as well as to Rob Schoevaart, Ar-jan Siebum and Arjan van Wijk for their recent research efforts on other cascade conversions at Leiden University, as part of the IBOS Programme (Integration of Biosynthesis and Organic Synthesis) of Advanced Chemical Technologies for Sustainability (ACTS) with industrial support from Friesland Foods and DSM. 

Tyrosine kinases are important mediators of the signaling cascade, determining key roles in diverse biological processes like growth, differentiation, metabolism and apoptosis in response to external and internal stimuli. Recent advances have implicated the role of tyrosine kinases in the pathophysiology of cancer. 

This chapter covers the recent advances in amidocarbonylations, cyclohydrocarbonylations, aminocarbonylations, cascade carbonylative cyclizations, carbonylative ring-expansion reactions, thiocarbonylations, and related reactions from 1993 to early 2005. In addition, technical development in carbonylation processes with the use of microwave irradiation as well as new reaction media such as supercritical carbon dioxide and ionic liquids are also discussed. These carbonylation reactions provide efficient and powerful methods for the syntheses of a variety of carbonyl compounds, amino acids, heterocycles, and carbocycles. 

In this chapter, the recent advances in amidocarbonylations, cyclohydrocarbonylations, aminocarbonylations, cascade carbonylative cyclizations, carbonylative ring-expansion reactions, thiocarbonylations, and related reactions are reviewed and the scope and mechanisms of these reactions are discussed. It is clear that these carbonylation reactions play important roles in synthetic organic chemistry as well as organometallic chemistry. Some of the reactions have already been used in industrial processes and many others have high potential to become commercial processes in the future. The use of microwave irradiation and substitutes of carbon monoxide has made carbonylation processes suitable for combinatorial chemistry and laboratory syntheses without using carbon monoxide gas. The use of non-conventional reaction media such as SCCO2 and ionic liquids makes product separation and catalyst recovery/reuse easier. Thus, these processes can be operated in an environmentally friendly manner. Judging from the innovative developments in various carbonylations in the last decade, it is easy to anticipate that newer and creative advances will be made in the next decade in carbonylation reactions and processes. 

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