Preparation method of biobased adipic acid

A preparation method of biobased adipic acid, comprising conducting a hydrogenation reaction on biobased muconic acid or biobased sodium muconate for preparing adipic acid in a hydrogenation reaction system under the action of a nickel-based hydrogenation catalyst;

• wherein
• a preparation method of the nickel-based hydrogenation catalyst comprises carrier pretreatment and metal nickel loading by a precipitation-deposition method, comprising:
• step A:
• putting a carrier into a Na2CO3 aqueous solution for ultrasonic pretreatment;
• and after solid-liquid separation, drying the carrier to obtain a pretreated carrier;
• step B:
• adding the pretreated carrier to water for ultrasonic treatment to obtain a carrier suspension;
• step C:
• mixing a nickel source with urea and the water to obtain a nickel source-urea mixed solution;
• step D:
• mixing the carrier suspension with the nickel source-urea mixed solution;
• sealing, stirring and impregnating;
• then unsealing, stirring and drying until the water completely volatilizes to obtain a dry nickel-based hydrogenation catalyst precursor;
• step E:
• reducing the dry nickel-based hydrogenation catalyst precursor at high temperature in a hydrogen atmosphere to obtain a nickel-based hydrogenation catalyst;
• in step A, the concentration of the Na2CO3 aqueous solution is 0.1-0.8 M, and a mass ratio of the Na2CO3 aqueous solution to the carrier is 5-15:1;
• in step C, a molar ratio of the urea to the nickel source is 2-8;
• in step C, a mass ratio of the nickel source to the water is 0.01-0.1;
• in step D, a mass ratio of the pretreated carrier to the nickel source is 0.65-10;
• the concentration of the carrier suspension is 20-100 g/L;
• the nickel-based hydrogenation catalyst is composed of carrier loaded metal nickel, wherein the average particle size of the metal nickel is 2.5-4.5 nm, and the specific surface area of the nickel-based hydrogenation catalyst is 50-300 m2/g;
• and the load of the metal nickel in the nickel-based hydrogenation catalyst is 2-40 wt %;
• the biobased muconic acid is cis-muconic acid prepared from biomass raw material;
• the biobased adipic acid is adipic acid converted from the biobased muconic acid.