Transformations of butyraldehyde in the presence of catalysts based on large-pore molecular sieves VPI-5 and AlPO4-8

Article abstract of DOI:10.1007/BF00700158

It was found that zeolite-like ctystalline aluminophosphates VPI-5, Si-VPI-5, and Mn-VPI-5 as well as those derived from them, AlPO4-8, SAPO4-8, and MnAPO4-8, are capable of catalyzing aldol condensation and crotonization of butyraldehyde (BA).Pd/AlPO4-8 is catalytically active in hydrocondensation of BA with H2 at atmospheric pressure.The activities in BA conversion to 2-ethylhexane-3-ol-1-al increase in following order: Mn-VPI-5 < Si-VPI-5 < VPI-5.The same order of activities is also found for AlPO4-8, SAPO4-8, and MnAPO4-8.These catalysts are characterized by a lower initial activity in crotonization of BA than M⁺NaX (CsNaX), but they are much more stable.Pd/AlPO4-8 catalyzes BA conversion to 2-ethylhexanal even in the absence of H2 feed to the reaction zone.The influence of catalyst pretreatments and experimental conditions on the catalyst structures and catalytic activities is discussed. - Key words: butyraldehyde; condendation; crystalline aluminophosphates; molecular sieves; VPI-5; AlPO4-8; catalysis.