The invention discloses a method for preparing natural
benzaldehyde. The method comprises the steps of gasifying cinnamyl
aldehyde at the temperature of 260 DEG C in a manner of taking a
composite oxide of two or three of Fe, Mo, W, Mn, Ca, Al, Cu and Zn as a catalyst and introducing O2 or air as an
oxygen supply, then, enabling cinnamyl
aldehyde gas to enter a fixed-
bed reactor, carrying out a gas-
solid catalytic
continuous reaction, and subjecting a product to molecular
distillation continuously through a molecular
distillation device at the temperature of 60 DEG C under the pressure of 100Pa, thereby obtaining the natural
benzaldehyde product. The method has the advantages that the process is simple and novel, the operation is simple, a
solvent is not required to be used, the separation is simple and convenient, the
reaction rate is high, the reaction process is
environmentally friendly, the natural degree of the
benzaldehyde is good, and the obtained product is high in purity.