Modified molecular sieve with high selectivity to ammonia nitrogen in waste water and preparation method thereof

摘要

A modified molecular sieve with high selectivity to ammonia nitrogen in waste water is provided. The main structure of the modified molecular sieve comprises: (1) a molecular sieve as a basic skeleton, and (2) functional materials loaded on the inner surface of the skeleton, wherein the functional materials are magnesium compound and phosphorus compound. The method for preparing the modified molecular sieve comprises the following steps: (1) dissolving magnesium salt into water to form a magnesium salt solution; (2) dissolving phosphoric acid into water to form a phosphoric acid solution; (3) adding the molecular sieve into the magnesium salt solution, followed by stirring, standing, drying, and baking; and (4) adding the baked modified molecular sieve loaded with magnesium compound into the phosphoric acid solution, followed by stirring, standing, drying, and baking. The modified molecular sieve can effectively solve the problem of generating large pressure drop when a fixed bed reactor is utilized as the way to treat waste water containing ammonia nitrogen, and can remove ammonia nitrogen in waste water with high selectively.