| 摘要 |
Boron phosphate is prepared by reacting concentrated phosphoric acid with finely powdered boric acid using, according to example 1, equimolecular amounts of reactants and then drying and finally cooking at 350 DEG C for three hours. The phosphate is used as catalyst in the vapour phase dehydration of alcohols, glycols, tetrahydrofurane and methyl tetrahydrofurane yielding olefines and di-olefines (see Group IV). Reactivation is effected by heating in air. The Specification as open to inspection under Sect. 91 describes, in Example 4, a boron phosphate catalyst in tablet form and containing 33 per cent. china clay, and cooked as described in example 1. This subject-matter does not appear in the Specification as accepted.ALSO:Olefines and diolefines are prepared by dehydrating alcohols, glycols, tetrahydrofurane or methyltetrahydrofurane in the vapour phase using a boron phosphate catalyst at an elevated temperature, preferably between about 250 DEG C. and 450 DEG C. The vaporized starting material may be passed over the heated catalyst together with a diluent gas such as nitrogen or carbon dioxide and also with a volatile catalyst containing combined phosphorus such as butyl or pyridine phosphate. In examples, methyl tetrahydrofurane is converted to piperylene and ethylenic alcohols which may be dehydrated to piperylene, butyl alcohol to butylene, and butylene glycol-1 : 3 to butadiene and ethylenic alcohols, employing a catalyst prepared by reacting equimolecular amounts of boric acid and phosphoric acid (see Group III). Reference is also made to the preparation of butadiene-1 : 3 from methyl vinyl carbinol and allyl carbinol. The Specification as open to inspection relates to the preparation of olefines and diolefines, generally, by dehydration using a boron phosphate catalyst and mentions the preparation of ethylene from ethyl alcohol, piperylene from pentane diol - 1 : 3, propylene from propanol, butadiene- 1 : 3 from propenyl carbinol and trimethyl ethylene and isopropyl ethylene from amyl alcohol, while an example describes the preparation of butadiene from tetrahydrofurane using a boron phosphate-china clay catalyst. This subject-matter does not appear in the Specification as accepted. p |
