▎ 摘　　要

NOVELTY - Preparing sulfonic acid solid acid catalyst comprises (1) dispersing the carbon material into water for suspension, adding the hydroxide as the acid center metal to the water dispersion system, stirring, precipitating, dispersing the spinning auxiliary agent in ethanol to obtain spinning auxiliary agent-ethanol dispersion system, mixing the hydroxide-carbon material water dispersion system with the spinning auxiliary agent-ethanol dispersion system, (2) adding the electrospinning dispersion system to the spinning apparatus for electrospinning, (3) calcining at high temperature, converting the hydroxide of the metal as the acid center into metal oxide and embedding in the carbon material to form composite skeleton for supporting sulfonic acid groups, (4) soaking the composite skeleton after cooling in concentrated sulfuric acid, and loading with sulfonic acid groups, and (5) filtering the product, washing, and drying to obtain sulfonic acid-based solid acid catalyst. USE - The catalyst is useful for preparing lactose (claimed). ADVANTAGE - The catalyst: uses electrospinning to limit the distribution of oxides with acid centers nested in carbon-based materials; removes by calcination as spinning auxiliary agent; and guarantees that the obtained composite skeleton has large specific surface area and fully exposes the acid center. DETAILED DESCRIPTION - Preparing sulfonic acid solid acid catalyst comprises (1) dispersing the carbon material into water for suspension, where the mass fraction of the carbon material is 3-8%, adding the hydroxide as the acid center metal to the water dispersion system in which the carbon material is suspended, stirring, precipitating, filtering, washing, vacuum drying to obtain the hydroxide-carbon material as the acid center metal, dispersing the hydroxide-carbon material as the acid center metal in water, where the mass fraction of the hydroxide-carbon material is 5-15%, dispersing the spinning auxiliary agent in ethanol to obtain spinning auxiliary agent-ethanol dispersion system, mixing the hydroxide-carbon material water dispersion system with the spinning auxiliary agent-ethanol dispersion system to obtain the electrospinning dispersion system, where the mass fraction of hydroxide-carbon material and spinning aid is 5-10%, (2) adding the electrospinning dispersion system to the spinning apparatus for electrospinning, where the aluminum foil collects the product, (3) calcining at high temperature, carbonizing of the spinning auxiliary agent in the obtained spinning, converting the hydroxide of the metal as the acid center into metal oxide and embedding in the carbon material to form composite skeleton for supporting sulfonic acid groups, (4) soaking the composite skeleton after cooling in concentrated sulfuric acid, and carrying out ultrasonic treatment, and loading with sulfonic acid groups, and (5) filtering the product, washing, and drying to obtain sulfonic acid-based solid acid catalyst. An INDEPENDENT CLAIM is also included for sulfonic acid-based solid acid catalyst prepared by the preparation method.