Reivindicaciones

1. Improved propylene oxide and styrene monomer co-production procedure by oxidation of ethyl benzene with molecular oxygen to yield ethyl benzene hydroperoxide, epoxydizing propylene with said hydroperoxide to form propylene oxide and 1-phenylethanol, the epoxydizing product then being submitted to alkaline rinsing and the separation, though distillation, of the propylene oxide, the excess ethyl benzene and the 1-phenylethanol, producing a heavy residue containing sodium and other metals as a result of the alkaline rinsing of one or more of the process currents, and dehydrating the 1-phenylethanol to styrene, the improvement being characterized by the dehydration of said heavy residue containing sodium and other metals in the presence of a strong inorganic acid as a catalyst, at temperatures of 150-250°C and pressures below the atmospheric pressure, using the strong inorganic acid in an amount exceeding the stoichiometric amount in respect to the sodium and other metals contained in the residue. 2. Procedure according to claim 1, characteristic in that the strong inorganic acid is sulfuric acid. 3. Procedure according to any of the claims 1 and 2, characteristic in that the amount of strong inorganic acid is higher than the one corresponding to the stoichiometric ratio in respect to sodium and the other metals present in the heavy residue, preferably selected in such a manner that, after reacting with the sodium and other metals present in the heavy residue, there remains an excess of free inorganic acid with a concentration in the order of 0.001 and 1% by weight. 4. Procedure according to any of the claims 1 to 3, characteristic in that the dehydration reaction of the heavy residue containing sodium and other metals in the presence of a strong inorganic acid is conducted at an absolute pressure of 50-400 mm.Hg. 5. Procedure according to any of the claims 1 to 4, characteristic in that the organic distillates obtained by dehydrating the sodium-containing heavy residue with a strong inorganic acid are submitted to distillation to obtain pure styrene and a fraction with a relatively high 2-phenylethanol content. 6. Procedure according to any of the claims 1 to 5, characteristic in that the non-volatile residues obtained by dehydrating the heavy residue containing sodium and other metals in the presence of a strong inorganic acid are submitted to filtering in order to separate the inorganic salts and obtain a residue substantially free of sodium and other metals that can adequately be used as fuel.