Process for reducing by-products in bisphenol A reaction system

A process for reducing by-products in a bisphenol A reaction system, comprising the following steps:

• (a) conveying mother liquor to a mother liquor recovery system, wherein the mother liquor is produced by reaction, concentration, crystallization and separation of phenol and acetone;
• (b) subjecting the mother liquor obtained from the mother liquor recovery system to contact with a sulfo-containing metal organic framework catalyst for an isomerization reaction;
• and
• (c) conveying a product obtained from the isomerization reaction to the mother liquor recovery system, performing crystallization and dephenolization to obtain bisphenol A;
• wherein the sulfo-containing metal organic framework catalyst in step (b) is formed by connecting metal ions or metal clusters and organic ligands through coordination bonds, and metal contained therein is one or a combination of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf;
• the organic ligands are one or a combination of terephthalic acid and trimesic acid;
• a pore size of the catalyst ranges from 0.5 nm to 10 nm, a specific surface area ranges from 100 m2/g to 5,000 m2/g, and an amount of sulfo groups ranges from 0.01 mmol/g to 8.0 mmol/g;
• the sulfo-containing metal organic framework catalyst is prepared by any one of a one-step synthesis preparation method, postsynthesis acid treatment preparation method, or postsynthesis oxidation treatment preparation method;
• the one-step synthesis preparation method of the sulfo-containing metal organic framework catalyst comprises the following steps:
• dissolving and stirring metal precursor salts and sulfo-containing organic ligands in N,N-dimethylamide and then static crystallizing the solution in a crystallization kettle at 140° C. to 160° C. for 24 hours to 36 hours, and subjecting an obtained crystallized product to filtering, washing with methanol and the N,N-dimethylamide, and drying, to obtain a sulfo-containing metal organic framework material;
• wherein the metal precursor salt is one or a combination of oxides, nitrates, chloride salts, and acetylacetonates of one or a combination of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf;
• the sulfo-containing organic ligands are one or a combination of benzoic acid with sulfo groups, terephthalic acid with sulfo groups, and trimesic acid with sulfo groups;
• the post-synthesis acid treatment preparation method of the sulfo-containing metal organic framework catalyst comprises the following steps:
• dissolving and stirring metal precursor salts and organic ligands in N,N-dimethylamide and then static crystallizing the solution in a crystallization kettle at 120° C. to 160° C. for 24 hours to 48 hours, and subjecting a crystallized product obtained in the crystallization kettle to filtering, washing with methanol and the N,N-dimethylamide, and drying, to obtain a metal organic framework precursor;
• and putting the obtained metal organic framework precursor into a polytetrafluoroethylene-lined reaction kettle, adding acidic liquor, sulfonating at 100° C. to 180° C. for 24 hours, and subjecting an obtained product to filtering, washing, and drying, to obtain a sulfo-containing metal organic framework material;
• wherein the metal precursor salt is one or a combination of oxides, nitrates, chloride salts, and acetylacetonates of one or a combination of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf;
• the organic ligands are one or a combination of terephthalic acid not containing amino groups or containing amino groups and trimesic acid not containing amino groups or containing amino groups;
• the metal organic framework precursor is formed by connecting metal ions or metal clusters and organic ligands through coordination bonds;
• and the acidic liquor is one or a combination of sulfuric acid, chlorosulfonic acid, and 1,3-propanesultone;
• and
• the post-synthesis oxidation treatment preparation method of the sulfo-containing metal organic framework catalyst comprises the following steps:
• dissolving and stirring metal precursor salts and sulfydryl-containing organic ligands in N,N-dimethylamide and then static crystallizing the solution in a crystallization kettle at 110° C. to 140° C. for 24 hours to 48 hours, and subjecting a crystallized product obtained in the crystallization kettle to filtering, washing with ethanol, and drying, to obtain a metal organic framework precursor;
• and putting the obtained metal organic framework precursor into a polytetrafluoroethylene-lined reaction kettle, adding oxidative liquor, oxidizing at 50° C. to 60° C. for 2 hours to 6 hours, and subjecting an obtained product to filtering, washing, and drying, to obtain a sulfo-containing metal organic framework material;
• wherein the metal precursor salt is one or a combination of oxides, nitrates, chloride salts, and acetylacetonates of one or a combination of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf;
• the organic ligands are one or more combinations of terephthalic acid containing alkyl sulfydryl or amino sulfydryl and trimesic acid containing alkyl sulfydryl or amino sulfydryl;
• the metal organic framework precursor is formed by connecting metal ions or metal clusters and organic ligands through coordination bonds;
• the oxidative liquor is hydrogen peroxide.