Ziegler technology

Ziegler-technology based on organic aluminium compounds in a hydrocarbon solvent (K. Ziegler, 1953 Alfol-Process, Conoco Epal-process, Ethyl Corp) ... 

The Ziegler technology produces a broad Poisson-distribution of more or less even-numbered fatty alcohols which are fractionated into blends and single cuts. The Oxo-process results in more or less highly branched, even- and odd-numbered alcohols. 

J. E. Ziegler, ed.. Handbook of Ion Implantation Technology, North-HoUand, New York, 1992. 

Two modifications of the duidized-bed reactor technology have been developed. In the first, two gas-phase duidized-bed reactors coimected to one another have been used by Mobil Chemical Co. and Union Carbide to manufacture HDPE resins with broad MWD (74,75). In the second development, a combination of two different reactor types, a small slurry loop reactor followed by one or two gas-phase duidized-bed reactors (Sphetilene process), was used by Montedision to accommodate a Ziegler catalyst with a special particle morphology (76,77). This catalyst is able to produce PE resins in the form of dense spheres with a diameter of up to 4—5 mm such resins are ready for shipping without pelletization. 

The Amoco reactor operates at 70—80°C and 2 MPa (300 psi) reactor pressure. The existence of several partially isolated compartments allows a semi-iadependent control of temperature as well as comonomer and hydrogen concentrations within each section, which ia turn offers a substantial control of the molecular weight and MWD of resias. Amoco technology also accommodates a large variety of polymerization catalysts, including Phillips and Ziegler catalysts. 

Similar to IFP s Dimersol process, the Alphabutol process uses a Ziegler-Natta type soluble catalyst based on a titanium complex, with triethyl aluminum as a co-catalyst. This soluble catalyst system avoids the isomerization of 1-butene to 2-butene and thus eliminates the need for removing the isomers from the 1-butene. The process is composed of four sections reaction, co-catalyst injection, catalyst removal, and distillation. Reaction takes place at 50—55°C and 2.4—2.8 MPa (350—400 psig) for 5—6 h. The catalyst is continuously fed to the reactor ethylene conversion is about 80—85% per pass with a selectivity to 1-butene of 93%. The catalyst is removed by vaporizing Hquid withdrawn from the reactor in two steps classical exchanger and thin-film evaporator. The purity of the butene produced with this technology is 99.90%. IFP has Hcensed this technology in areas where there is no local supply of 1-butene from other sources, such as Saudi Arabia and the Far East. 

The principal iadustrial production route used to prepare fatty amines is the hydrogenation of nitriles, a route which has been used since the 1940s. Commercial preparation of fatty amines from fatty alcohols is a fairly new process, created around 1970, which utilizes petrochemical technology, Ziegler or Oxo processes, and feedstock. 

The next major commodity plastic worth discussing is polypropylene. Polypropylene is a thermoplastic, crystalline resin. Its production technology is based on Ziegler s discovery in 1953 of metal alkyl-transition metal halide olefin polymerization catalysts. These are heterogeneous coordination systems that produce resin by stereo specific polymerization of propylene. Stereoregular polymers characteristically have monomeric units arranged in orderly periodic steric configuration. 

K. Ziegler (Millheim/Ruhr) and G. Natta (Milan) the chemistry and technology of high polymers. 

Fink G, Miihlhaupt R, Brintzinger HH (eds) (1995) Ziegler catalysts recent scientific innovations and technological improvements. Springer, Berlin Heidelberg New York... 

Polymers manufactured via single site catalyst technologies, because of the unique chemical catalytic environment, exhibit a more controlled molecular weight distribution and tacticity than seen with Ziegler-Natta catalyst systems. 

For reviews and books, (a) West, R. J. Organomet. Chem. 1986, 300, 327. (b) Miller, R. D. Michl, J. Chem. Rev. 1989, 89, 1359. (c) Ziegler, J. M. Fearson, F. W. G. (Eds.). Silicon-Based Polymer Science, Advances in Chemistry Series, Vol. 224, American Chemical Society, Washington, DC, 1990. (d) Michl, J. West, R. In Silicon-Containing Polymers The Science and Technology of Their Synthesis and Applications. Kluwer, Dordrecht, 2000, Chapter 18. 

Multiphase copolymers, Ziegler-Natta catalysts for, 26 535, 537-540 Multiphase laminar flow patterning, in microfluidics, 26 961 Multiphase reactions, in microbial transformations, 16 412-414 Multi-phase reactors, 21 333-335 Multiphoton effects, in photochemical technology, 19 109... 

Polyolefin industry, catalysts in, 26 503 Polyolefin (PO) resins, 17 699-700 technologies and uses for, 17 707-708 Polyolefin products, Ziegler-Natta catalysts for, 26 533-544 Polyolefins, 10 518... 

The annual production of various polymers can be measured only in billion tons of which polyolefins alone figure around 100 million tons per year. In addition to radical and ionic polymerization, a large part of this huge amount is manufactured by coordination polymerization technology. The most important Ziegler-Natta, chromium- and metallocene-based catalysts, however, contain early transition metals which are too oxophiUc to be used in aqueous media. Nevertheless, with the late transition metals there is some room for coordination polymerization in aqueous systems [1,2] and the number of studies published on this topic is steadily growing. 

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