Method for preparing anisic aldehyde by hydrogen peroxide oxidation of anethole through microwave aided acid catalysis

Abstract

The invention discloses a method for preparing anisaldehyde by catalyzing hydrogen peroxide by an acid to oxidize anethole with the assistance of microwave, which comprises the following steps: (1) a solvent, namely absolute ethyl alcohol, an acid catalyst and 5 to 30 percent hydrogen peroxide solution are added into the anethole, and the mixture is placed into a microwave reactor; (2) the mixture reacts for 10 to 120 minutes under microwave power of between 24 and 300 w; (3) a reaction liquid is concentrated to remove ethanol and then is cooled to room temperature, and a ferrous sulfate solution is added until starch iodide paper can not be changed into blue; (4) vapor is distilled to produce volatile oil; and (5) an anhydrous sodium sulfate drier is used to dry, and the anisaldehyde can be obtained through centrifugal separation. The method effectively solves the problems that the prior industrial method for preparing the anisaldehyde has low yield, complicated operation, difficult treatment of three-waste pollution, serious corrosion of equipment, high cost, and large energy consumption, improves the yield of the anisaldehyde, reduces production cost, and provides the method with simpler technology and more environment-friendly production for the preparation of the anisaldehyde by the anethole.

Description

technical field [0001] The invention relates to a method for preparing anisaldehyde, in particular to a method for preparing anisaldehyde by microwave-assisted acid-catalyzed oxidation of anethole with hydrogen peroxide. Background technique [0002] Anisaldehyde is one of the main components in star anise oil. Anisaldehyde has the aroma of hawthorn flower, which is fragrant and long-lasting. It also has strong antioxidant properties. It is widely used in the deployment of daily chemical flavors and food flavors, and is widely used in the pharmaceutical industry. Amoxicillin, an antimicrobial drug, can be used as an excellent brightener for cyanide-free galvanizing DE additives in the electroplating industry. In agriculture, anisaldehyde can be used as insecticides, insecticide additives, and biological growth inhibitors. But at present, the annual output of star anise oil in the country is more than 5,000 tons, the annual output of anethole is about 900 tons, and the annual...

AI Technical Summary

Problems solved by technology

At present, the industrial preparation of anisaldehyde mainly includes the traditional red alum sodium method and manganese dioxide method to oxidize anethole. The yield of anisaldehyde is lower than 50%, the preparation conditions are harsh, the pollution of "three wastes" is difficult to deal with, and the equipment is seriously corroded. Ozone oxidation The yield of anisaldehyde in the method is 54.48%, the equipment cost is high, and the operation is complicated; the yield of anisaldehyde in the electro-oxidation method is 52%, the production energy consumption is large, the equipment requirements are high, and the operation is complicated

The yield of anisaldehyde prepared by the current method is far from being able to meet the demand of producing spice products