Method for treating an MTBE-contaminated aqueous solution

A method for treating an MTBE-contaminated aqueous solution, comprising:

• burning a liquid fuel and collecting a raw fly ash by electrostatic precipitator;
• forming acid-treated fly ash particles by stirring the raw fly ash with nitric acid to form a slurry;
• and
• washing the slurry to produce the acid-treated fly ash particles which consist of carbon, oxygen, and sulfur;
• doping the acid-treated fly ash particles with AgNO3 and calcining to form an adsorbent composition comprising the acid-treated fly ash particles and silver oxide nanoparticles;
• the silver oxide nanoparticles have diameters in a range of 1-10 nm;
• wherein the silver oxide nanoparticles are present on the surface and in pore spaces of the acid-treated fly ash particles;
• wherein the adsorbent composition contains particles having sizes in a range of 100 nm to 2.5 μm and a BET surface area of at least 16.789 m2/g,
• wherein the acid-treated fly ash particles and the silver oxide nanoparticles are present in the adsorbent composition at mass percentages of 50-90% and 10-50%, respectively, based on the total weight of the adsorbent composition;
• contacting the MTBE-contaminated aqueous solution with the adsorbent composition in a tank for 30 minutes to 5 hours to adsorb the MTBE and form a purified aqueous phase;
• then
• separating the purified aqueous phase from the adsorbent composition.