SEQUENTIAL CHEMICAL BIOLOGICAL OXIDATION OF CHLORENDIC ACID/

Chlorendic acid, a fire retardant, was subjected to sequential chemica l/biological oxidation. Degradation of chlorendic acid was achieved by ozonation with chlorinated and non-chlorinated by-product production. The destruction of chlorendic acid and by-product distribution was a function of ozone contact time. After 450 min of ozonation, chlorendic acid and TOC removal percentages equaled 98% and 62.5%, respectively. When subject to 210 min of UV oxidation, chlorendic acid and TOC remo val equaled 70 and 31%, respectively. With combined ozone/UV, near com plete removal of chlorendic acid and TOC was achieved in 90 and 120 mi n, respectively. In biodegradation testing, chlorendic acid was not de gradable. Biodegradation efficiency (DOG removal) of chlorendic acid o zonation by-products was a function of ozone contact time and approach ed 80%. Chlorendic acid UV oxidation products (210 min contact time) w ere poorly biodegraded. Ozone/UV oxidation products (40 min contact ti me) from chlorendic acid achieved 89% biodegradation. Biodegradation r ates of chlorendic acid chemical oxidation by-products also were asses sed. Based on the computed biokinetic values of biodegradation rates f or the chemical oxidation products of chlorendic acid are sufficiently high to enable use of existing biological process infrastructure for treatment of chemical oxidation products. Copyright (C) 1996 Elsevier Science Ltd