Preparation and acidic properties of nano-porous lanthanum phosphate by the addition of urea

Urea was added to the preparation of lanthanum phosphate from phosphoric acid and lanthanum nitrate solutions. The precipitations prepared in various conditions and their thermal products were estimated from the view of the chemical composition, powder and acidic properties. The addition of urea had much influence on specific surface area, pore size distribution, particle shape and size of lanthanum phosphate prepared in aqueous solution, without the change of chemical composition of phosphates. The amount of included urea in lanthanum phosphate was estimated from NH3-TPD curves. Further, the adsorption of trimethylamine on lanthanum phosphate was improved by the addition of urea. The addition of urea in the preparation of phosphate is one of the useful and conventional methods for the design of functional materials.