Solvay advantages

As indicated, this process is defined as mechanical recycling, since the PVC polymer is not broken down into its monomers. Yet, a main difference with classical mechanical recycling is that in the latter the full PVC formulation is kept intact. Here the components that make up the full formulation are separated. This results in the important advantage that the Vinyloop process can deal with rather complicated formulations. According to Solvay the regenerated PVC is comparable in quality to the primary product. 

Ernest Solvay, a Belgian chemist, designed a tower in which carbon dioxide reacted efficiently with solid salts. The Solvay process had enormous advantages over the Leblanc process It did not generate as much waste and pollution its raw materials, brine and ammonia, were readily available (the latter from gasworks) less fuel was used, and no sulfur or nitrate was involved. In spite of its higher capital costs, it was rapidly adopted and soon became the major source of alkali. 

A shift to the processing of substantial alternate natural mineral sources of sodium carbonate in the U.S. has eliminated the calcium chloride disposal problems of the Solvay process for sodium carbonate production. Coupling this advantage to the much lower capital cost of a natural sodium carbonate plant has contributed to the shift away from synthetic sodium carbonate in the U.S. [13] (Table 7.3). Kenya is the only other country reported to be recovering natural sodium carbonate and was operating at 260,000 metric toimes in 2001 [19]. China, the second largest producer, and all other world producers still rely heavily on the ammonia-soda process [17, 24] (Table 7.4). 

Currently, the only commercially available polysulfone blend is a poly-phenylsulfone/polysulfone blend (Acudel PPSU/PSU, Solvay) (Table 19.35). It offers a cost and processing advantage over neat PPSU, while retaining good resistance to hot chlorinated water, useful in plumbing system components such as ball valves, connectors, and housings. The blend is opaque (immiscible) and has a lower notched Izod than PPSU but is more cost-effective. 

Fluorinated fluids such as Galden of Solvay or HFE of 3M can be used in electrochemical devices for heat exchange purpose thanks to their dielectric property and chemical inertness. One advantage of these fluids is that, in case of... 

MgCl2(l) is pictured in Figure 21-14. Like the Solvay process for making NaHCOs, the Dow process takes advantage of simple chemistry and recycling. 

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