▎ 摘　　要

NOVELTY - Method for synthesizing lanthanum-doped graphene oxide nano-composite fluorine-removing agent, involves (i) using graphene oxide, lanthanum chloride hydrate and aqueous ammonia as raw materials, and reacting, (ii) taking graphene oxide solid, hydrated lanthanum chloride solid and water, (iii) uniformly mixing the graphene oxide solid with water, ultrasonically dispersing, and centrifuging to remove insoluble impurities to obtain remaining upper liquid which is a colloidal solution of graphene oxide, (iv) adding hydrated lanthanum chloride solid to graphene oxide colloidal solution, stirring, and ultrasonically dispersing to obtain a mixed solution, (v) dripping 8 mol/l aqueous ammonia to mixed solution to adjust pH value of the system, (v) placing system in a water bath for continuous stirring, and aging at room temperature, (vii) filtering, and washing with water until filtrate is neutral, and (viii) drying filter residue, and crushing. USE - The method is used for synthesizing lanthanum-doped graphene oxide nano-composite fluorine-removing agent. ADVANTAGE - The method has simple process, and is easy to operate and suitable for mass production. DETAILED DESCRIPTION - Method for synthesizing lanthanum-doped graphene oxide nano-composite fluorine-removing agent, involves (i) using graphene oxide, lanthanum chloride hydrate and aqueous ammonia as raw materials, and reacting, (ii) taking graphene oxide solid, hydrated lanthanum chloride solid and water, (iii) uniformly mixing the graphene oxide solid with water, ultrasonically dispersing, and centrifuging to remove insoluble impurities to obtain remaining upper liquid which is a colloidal solution of graphene oxide, (iv) adding the hydrated lanthanum chloride solid to the graphene oxide colloidal solution, stirring to a uniform state, and ultrasonically dispersing to obtain a mixed solution, (v) dripping 8 mol/l aqueous ammonia to the mixed solution to adjust the pH value of the system, (v) placing the system in a water bath for continuous stirring, and aging at room temperature, (vii) filtering, and washing with water until the filtrate is neutral, and (viii) drying the filter residue, and crushing to obtain a lanthanum hydroxide/graphene oxide carbon-based nanocomposite fluorine-removing agent.