Method for preparing bio-based 1,4-butanediol

A method for preparing bio-based 1,4-butanediol (BDO), comprising:

• mixing succinic acid from a bio-based source and an alcohol compound to obtain a mixture, and subjecting the mixture to esterification to obtain an oligomer polyester;
• wherein the succinic acid from the bio-based source is derived from biological fermentation;
• subjecting the oligomer polyester to hydrogenation reduction in the presence of a catalyst to obtain a 1,4-BDO crude product;
• wherein a molar ratio of hydrogen used in the hydrogenation reduction to the oligomer polyester is in a range of 80-200:1;
• the catalyst is a supported copper-based catalyst, the supported copper-based catalyst is prepared by a process comprising the following steps:
• (1) mixing copper nitrate hexahydrate, aluminum nitrate nonahydrate, an active metal salt, and water to obtain a metal ion salt solution, wherein a metal in the active metal salt is selected from the group consisting of manganese, nickel, cobalt, zinc, cerium, and zirconium, wherein a molar ratio of the copper nitrate hexahydrate, the metal in the active metal salt, and the aluminum nitrate nonahydrate is in a range of 2.7:0.7:1 to 5:1:2;
• (2) mixing sodium hydroxide, sodium carbonate, and water to obtain an alkaline solution precipitant;
• (3) adding the metal ion salt solution and the alkaline solution precipitant to a reactor at 60° C. to form a reaction system, and subjecting the reaction system to precipitation to obtain a precipitated product, wherein a pH value of the reaction system is maintained at a range of 8 to 10;
• (4) aging the precipitated product at 70° C. for 24 h to obtain a ternary hydrotalcite-like compound;
• and
• (5) subjecting the ternary hydrotalcite-like compound to calcination and activation in sequence to obtain the supported copper-based catalyst, the calcination being conducted at a temperature of 500° C. to 600° C. for 0.5 h to 8 h;
• and
• purifying the 1,4-BDO crude product to obtain the bio-based 1,4-BDO.