Solvay et Cie

Solvay et Cie S.A., Centre Recherche, rue de Ransbeek, 310, 1120 Brussels, Belgium... 

The Unipol process employs a fluidized bed reactor (see Section 3.1.2) for the preparation of polyethylene and polypropylene. A gas-liquid fluid solid reactor, where both liquid and gas fluidize the solids, is used for Ziegler-Natta catalyzed ethylene polymerization. Hoechst, Mitsui, Montedison, Solvay et Cie, and a number of other producers use a Ziegler-type catalyst for the manufacture of LLDPE by slurry polymerization in hexane solvent (Fig. 6.11). The system consists of a series of continuous stirred tank reactors to achieve the desired residence time. 1-Butene is used a comonomer, and hydrogen is used for controlling molecular weight. The polymer beads are separated from the liquid by centrifugation followed by steam stripping. 

Material. The PVDF resin grade Solef 1010 from Solvay et Cie was used in this study. This grade had been found to exhibit good melt extrusion properties for blown film production (M 351,000,... 

The loop reactors, which are recycled tubular reactors, are used by the Phillips Petroleum Co. and Solvay et Cie. The Phillips process is characterized by the use of a light hydrocarbon diluent such as isopentane or isobutane in loop reactors which consist of four jacketed vertical pipes. Figure 1 shows the schematic flow diagram for the loop reactor polyethylene process. The use of high-activity supported chromium oxide catalyst eliminates the need to deash the product. This reactor is operated at about 35 atm and 85-110° C with an average polymer residence time of 1.5 hr. Solid concentrations in the reactor and effluent are reported as 18 and 50 wt %, respectively. The reactor diameter is 30 in. (O.D.) and the length of the reactor loop is about 450 ft. 

A.Lecloux, c/o Solvay et cie, Laboratoire Central,Rue de Ransbeek, 310-1120 Bruxelles,Belgium. 

The Energy Content of Plastics Articles, British Plastics Federation, London, 1986. Company brochure, Solvay et Cie, PVC and The Environment, 1986. 

Solvay et Cie S.A., Laboratoire Central, Rue de Ransbeek 310, B-1120 Bruxelles, Belgique Fink, G.(19)... 

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