Polymer Engineering process catalyst

The acid cracking catalysts produce carbonium ions by the addition of protons to polyolefin chains or by abstraction of hydride ions from hydrocarbon molecules. This is followed by chain scission, which yields C30-C50 oligomeric hydrocarbons. Secondary cracking by P-scission of the C30-C50 hydrocarbons yields liquid (C10-C25) hydrocarbon fuel. Specific advantages of the Polymer-Engineering Process include ... 

Vol. 1 Polymer Engineering Vol. 2 Filtration Post-Treatment Processes Vol. 3 Multicomponent Diffusion Vol. 4 Transport in Porous Catalysts... 

Slurry (Suspension) Polymerization. This polymerization technology is the oldest used for HDPE production and is widely employed because of process engineering refinement and flexibHity. In a slurry process, catalyst and polymer particles are suspended in an inert solvent, ie, a light or a... 

Polymer-Engineering A catalytic process for making diesel fuel from waste plastics. Developed by C. Koch at Alphakat GMBH, Germany, and now offered by Polymer-Engineering, Germany. A zeolite catalyst is used, and the product is called NanoFuel Diesel. Plants have been built in Germany, Mexico, Japan, and South Korea. 

Figure 15.11 Overview of the NanoFuel catalytic diesel process process developed process developed by Dr Christian Koch. The process converts waste plastics by catalytic depolymerization at 270-370°C in the presence of an ion-exchanging catalyst based on a highly active Y sodium aluminosilicate zeolite catalyst. (Courtesy of Polymer-Engineering, Bielefeld, Germany)...

In most cases, each facility is responsible for only a few specific reaction steps. Polyethylene or polypropylene production facilities are supplied with the monomer material, from which they then produce the plastic in a single reaction step. In PS and PET production, a few additional steps are required to produce the monomer. The technical know-how covers the chemical stmcture of the polymer molecules, the catalysts, and the process engineering. The end result is comprised of high-performance materials with specifically engineered application properties. For instance, PS types are produced that are either highly transparent (clear as glass) or particularly impact resistant. 

Reaction engineers are expected to transform laboratory discoveries of new synthesis routes or design concepts into economic, safe, and environmentally compatible processes. The highly competitive industrial environment has added the need to shorten the time interval in which this task has to be completed and to decrease the production price. This motivated several innovations. The first was development of novel catalysts, which increased the yield in existing processes, such as the novel Kellogg ammonia-synthesis process, which uses the much more active BP catalyst. Other catalysts were designed to provide either new synthesis routes, such as the production of synthesis gas by direct oxidation, or new products, such as production of novel polymers by metallocene catalysts. 

By means of genetic engineering, including cloning and site-directed mutagenesis, it has become possible for modern synthetic chemists to utilize a sufficient amount of isolated enzyme catalysts and to modify the reactivity, stability, or even specificity of enzymes. Therefore, polymerizations catalyzed by isolated enzyme are expected to create a new area of precision polymer syntheses. Furthermore, enzymatic polymerizations have great potential as an environmentally friendly synthetic process of polymeric materials. 

The field of chemical kinetics and reaction engineering has grown over the years. New experimental techniques have been developed to follow the progress of chemical reactions and these have aided study of the fundamentals and mechanisms of chemical reactions. The availability of personal computers has enhanced the simulation of complex chemical reactions and reactor stability analysis. These activities have resulted in improved designs of industrial reactors. An increased number of industrial patents now relate to new catalysts and catalytic processes, synthetic polymers, and novel reactor designs. Lin [1] has given a comprehensive review of chemical reactions involving kinetics and mechanisms. 

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