Degradation Rate Of Carbamazepine Research Articles

Sonochemical degradation of the persistent pharmaceutical carbamazepine

The objective of this work was to evaluate the potential of a sonochemical oxidation process for the degradation of carbamazepine (CBZ). Several factors, such as electrical power, treatment time, pH and initial concentration of CBZ were investigated. Using a 24 factorial matrix, the best performance for CBZ degradation (90.1% of removal) was obtained with an electrical power of 40 W, a treatment time of 120 min and an initial pH of 10.0 imposed in the presence of 6.0 mg L−1 of CBZ. The treatment time and the calorimetric power were the most influential parameters on the degradation rate of CBZ. Subsequently, the optimal experimental parameters for CBZ degradation were investigated using central composite design. The sonochemical oxidation process, applied under optimal operating conditions (at an electrical power of 43 W for 116 min), oxidized 86 and 90% of the initial CBZ concentration of 5.62 mg L−1 and 8.05 μg L−1, respectively. During the sonochemical process, CBZ was primarily transformed into anthranilic acid and acridine.

Thermally activated persulfate (TAP) oxidation of antiepileptic drug carbamazepine in water

Sulfate radicals-based advanced oxidation processes have been applied in water treatment and in situ chemical oxidation. Batch experiments were conducted to investigate the influencing factors including persulfate dosage, initial carbamazepine (CBZ) concentrations, solution pH, coexisting inorganic anions and cations on the decomposition of CBZ using thermally activated persulfate (TAP) technology. The results showed that TAP oxidation was efficient process for the CBZ degradation in water. The generation of sulfate radicals was accounted for the CBZ degradation in TAP system. The CBZ degradation rate constant increased as persulfate dosage increased and decreased as the initial CBZ concentrations increased. The CBZ decomposition rate decreased with the increasing pH and the best degradation occurred at pH 3. The exception was the strong alkaline condition under which a higher CBZ degradation performance was achieved. Coexisting inorganic anions slowed down the CBZ degradation to different degrees and the inhibiting effect abided by the following order: CO32->HCO3->Cl->SO42->NO3-. In contrast, coexisting cations could significantly enhance the CBZ degradation, and the promoting effect was in the order of Fe2+>Cu2+>Fe3+. In this study, six major intermediate products were generated during the TAP oxidation.

Treating wastewater from a pharmaceutical formulation facility by biological process and ozone

Wastewater from a pharmaceutical formulation facility (TevaKS, Israel) was treated with a biological activated-sludge system followed by ozonation. The goal was to reduce the concentrations of the drugs carbamazepine (CBZ) and venlafaxine (VLX) before discharging the wastewater to the municipal wastewater treatment plant (WWTP). Both drugs were detected at extremely high concentrations in TevaKS raw wastewater ([VLX]=11.72±2.2mg/L, [CBZ]=0.84±0.19mg/L), and resisted the biological treatment. Ozone efficiently degraded CBZ: at an O3 dose-to-dissolved organic carbon ratio of 0.55 (O3/DOC), the concentration of CBZ was reduced by >99%. A lower removal rate was observed for VLX, which was decreased by ∼98% at the higher O3/DOC ratio of 0.87. Decreasing the pH of the biologically treated effluent from 7 to 5 significantly increased the ozone degradation rate of CBZ, while decreasing the degradation rate of VLX. Ozone treatment did not alter the concentration of the effluent's DOC and filtered chemical oxygen demand (CODf). However, a significant increase was recorded (following ozonation) in the effluent's biological oxygen demand (BOD5) and the BOD5/CODf ratio. This implies an increase in the effluent's biodegradability, which is highly desirable if ozonation is followed by a domestic biological treatment. Different organic byproducts were formed following ozone reaction with the target pharmaceuticals and with the effluent organic matter; however, these byproducts are expected to be removed during biological treatment in the municipal WWTP.

Degradation of carbamazepine by Trametes versicolor in an air pulsed fluidized bed bioreactor and identification of intermediates

The paper describes the aerobic degradation of carbamazepine (CBZ), an anti-epileptic drug widely found in aquatic environment, from Erlenmeyer flask to bioreactor by the white-rot fungus Trametes versicolor. In Erlenmeyer flask, CBZ at approximately 9 mg L −1 was almost completely eliminated (94%) after 6 d, while at near environmentally relevant concentrations of 50 μg L −1, 61% of the contaminant was degraded in 7 d. Acridone, acridine, 10,11-dihydro-10,11-dihydroxy-CBZ, and 10, 11-epoxy-CBZ were identified as major metabolites, confirming the degradation of CBZ. The degradation process was then carried out in an air pulsed fluidized bioreactor operated in batch and continuous mode. Around 96% of CBZ was removed after 2 days in batch mode operation, and 10,11-dihydro-10,11-epoxycarbamazepine was found as unique metabolite. In bioreactor operated in continuous mode with a hydraulic retention time of 3 d, 54% of the inflow concentration (approx. 200 μg L −1) was reduced at the steady state (25 d) with a CBZ degradation rate of 11.9 μg CBZ g −1 dry weight d −1. No metabolite was detected in the culture broth. Acute toxicity tests (Microtox) indicated that the final culture broth in both batch and continuous mode operation were non toxic, with 15 min EC50 values of 24% and 77%, respectively.