A preparation method of bismuth silicate powder photocatalyst

The invention relates to a preparation method for bismuth silicate powder photocatalyst. At first pentahydrate bismuth nitrate and active agent on the surface of a segmented copolymer are dissolved in acetic acid to form uniform clear solution, and then silicate ester is added into solution containing bismuth according that the mol ratio of bismuth to silicon is equal to 12:1, and is fully mixed to form uniform sol. After aging, the solution is moved into an autoclave to be hermetically crystallized, so as to obtain the composite oxide gel of the bismuth and the silicon, and after being filtered, cleaned, and dried, at last precursor powder is roasted in the air environment, namely, the bismuth silicate powder photocatalyst of the granularity with micron size is obtained. The invention can stably and uniformly obtain the bismuth silicate powder with good crystallinity under the lower temperature, and the granularity of the photocatalyst is larger, thereby being convenient for being separated from a water body