Treatment of pharmaceuticals/antibiotics in wastewater by combination of zeolite adsorbent with ionizing radiation

The technology for the decomposition of trace amounts of halogenated pharmaceuticals/antibiotics was developed in wastewater by use of the combination method of zeolite adsorbent and ionizing radiation. Toxicity test was conducted using a luminescence bacterium on the irradiation of aqueous solution of 2-chlorophenol (2-ClPh) as a simple model of halogenated pharmaceuticals/antibiotics. Toxicity of 2-ClPh solution increased with the increase in γ-ray dose. The toxicity after γ-ray irradiation originates only in neither 2-ClPh nor primary products, but it is thought that it is based on a synergistic effect including organic acid or aldehyde. HMOR, a hydrophobic high-silica mordenite-type zeolite, was employed to concentrate 2-ClPh on it. HMOR adsorbed above 99% of 2-ClPh from dilute aqueous solutions. The yield of Cl⁻ production in HMOR mixture corresponded to the aqueous solution containing 10 fold higher concentration of dissolved 2-ClPh. Clofibrate and triclosan, one of chlorinated pharmaceuticals/antibiotics, in real wastewater were treated by use of the combination method of HMOR and ionizing radiation. Production yield of Cl^- by use of the adsorbent was about twice higher than that in aqueous solution, and HMOR was contributed for effective reduction of chlorinated pharmaceuticals/antibiotics in real wastewater. (author)