| 摘要 |
<p>Reaction is carried out in the gaseous phase at 740-780 degrees C; the reaction mixture (contng. malonic dinitrile, and as impurities, maleic and fumaric dinitriles), is either 1) subjected to a Diels-Alder reaction to convert the maleic and fumaric dinitriles to the corresponding Diels-Alder adducts (which may then be separated from the malonic dinitrile); or 2) subjected to selective hydrogenation using a calculated amount of hydrogen and a hydrogenation catalyst, so as to convert the maleic and fumaric dinitriles to succinic dinitrile, which may be separated off by fractional distillation. The process gives a higher yield of malonic dinitrile than prior art processes, with a purity of at least 99%.</p> |
