- Preparation method of p-n Type photocatalytic TiO2 Coatings and its applications to waste water treatment and water reclamation system.

摘要

PURPOSE: Provided are a method of making coating layer for p and n type titanium oxide photocatalyst and its treatment of waste and sewage water to eliminate organic compounds, nitrogen, phosphorous and sulfur compound for wastewater reclamation and reusing system. With energy source of DC for buoyance electrolysis method and AC for redox decomposition method are used in the water treatment. CONSTITUTION: The process of making p type titanium oxide catalyst comprises mixing a) tetraethyl orthotitanate and 1-7wt.% aqueous hydrochloric acid or sulfuric acid/alcohol in a mole ratio of 10-50 for 2-8 hours for hydrolysis; b) mixing the above titanium acid oxide with methanol, and impregnating, by photo reduction method, 0.5wt.% (to 100mol.wt.% titanium oxide) platinum chloride aqueous solution and 0.5wt.% silver chloride in 10% ammonium water as hydrocarbon absorbent activator; c) impregnating 5wt.% tungsten trioxide as oxidizer in 7.5wt.% lithium hydroxide aqueous solution with 1.5-3.5mol.wt.% bismuth by treating with 2-5mol.wt.%, 7wt.% aqueous bismuth chloride solution; d) mixing 1-5mol.wt.% oxidation type cobalt phosphate and 5-10mo.wt.% ferrite with the function of controlling energy band gap of titanium oxide and oxygen carrier function; e) mixing polysiloxane polymer as binder with compositions of a) to d) in a wt. ratio of 100:120-250 at room temp. for 6-24 hours and coating this dispersed p-type titanium oxide coating composition on metal and heating at 400-600deg.C for 6-12 hours to make p-type titanium coating layer with the dried thickness of coating of 15-30 micrometer. Similar way n-type titanium coating layer is prepared.