Method for preparing benzaldehyde by nano MnO2

This invention relates to the preparation of benzaldehyde by using nanometer manganese oxide (MnO2). It contains steps of: (1), providing an electrolytic bath with its anode chamber and cathode chamber, with positive electrode and negative electrode respectively, and isolated from each other by cation-exchange membrane; (2), adding manganese sulfate solution and phenylmethanol solution at optional ratio as electrolytic solution, and sulfuric acid solution is added into the cathode chamber as its electrolytic solution; (3), powering-on the electrodes to proceed the electrolytic reactioin, at the same time agitating the electrolytic solution in cathode chamber; (4), providing an ultrasonic generator, putting said electrolytic tank into said ultrasonic generator equipment, making the electrolytic reaction being proceeded under the ultrasonic wave; (5), the above mentioned equipment is placed in the condition of 60-95 deg.C for 0.5-3 Hrs; (6), the liquid product is then subjected to procedures of extraction, vacuum distillation to produce the final product benzaldehyde.