Ziegler-Natta technology

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 The catalyst is removed by vaporizing Hquid withdrawn from the reactor in two steps classical exchanger and thin-film evaporator.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. 

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. 

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. 

Commodity high pressure PE-LD grades have a broad polydispersity and they contain small amounts of LCB, which results in excellent melt flow properties. Due to the broad polydispersity (PD), the mechanical properties are inferior, even compared with conventional Ziegler-Natta resins. However, narrow PD metallocene resins have poor processing properties. Recent advances in catalyst technology, have resulted in metallocene polyethenes that contain small amounts of LCB to ease the processability. 

EPM and EPDM, generally referred to as EPDM are classically produced via Ziegler-Natta catalysis in solution or slurry processes. Over the last decade metallocene catalysis [4, 5] and gas phase technology [6] have been developed. EPDM is produced on a commercial scale in a variety of chemical compositions. Typically, the ethylene content... 

An analogous technology commercialized by IFP, Paris, is their continuous, chloroaluminate ionic liquid dimerization of //-butene to isooctane, promoted by a Ziegler-Natta-type homogeneous catalyst. The poorly miscible isooctane product is readily separated. 

In only a few polymerization processes are metallocene catalysts used in a soluble form. Supported metallocene catalysts are preferred for the production of polyethylene or isotactic polypropylene on an industrial scale, especially in the slurry and gas-phase processes. To use them in existing technological processes (drop-in technology) as replacements for the conventional Ziegler-Natta catalysts, the metallocenes have to be anchored to an insoluble powder support, including silica, alumina, and magnesium dichloride (208-217). Various methods of anchoring catalysts to supports are possible (Fig. 25) ... 

Nobel Prize Chemistry to Karl Ziegler and Giulio Natta for their discoveries in the field of the chemistry and technology of high polymers (Ziegler-Natta... 

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