ELECTROCHEMICAL OXIDATION MEDIATED COBALT(III) FOR AMOXICILLIN WASTEWATER TREATMENT

• Main Author: Herlina
• Format: Dissertations
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/54983
• Institution: Institut Teknologi Bandung

Amoxicillin is a ?-lactam antibiotic one of the penicillin groups. Amoxicillin is absorbed quickly and well in the digestive system, is independent of the presence of food in the stomach and after one hour its concentration in the blood is very high cause high effectiveness. Amoxicillin is excreted primarily through the kidneys or disposed of the urine contained in the active form. These antibiotics can weaken the gram positive and gram negative bacteria. Amoxicillin is commonly used in human medicine and veterinary practice and has been used in several studies as the target compound representing the antibiotics family. Been used to treat diseases caused by the disease germs that are sensitive to amoxicillin. Some diseases are usually treated with amoxicillin include middle ear infection, inflammation of the tonsils, sore throat, inflammation of the larynx, bronchitis, pneumonia, urinary tract infections, and infections of the skin. The irrational used of antibiotics cause varieties of risk factors, including the immunity of germs to antibiotics (resistance), increased drug side effects and even death. It is reported that the bacteria are resistant to most classes of antibiotics. The use of antibiotics is very broad cause antibiotic resistance factor is an issue that is very popular lately. Results of Antimicrobial Resistant research in Indonesia (Amrin-Study) 2000-2005 on 2494 individuals in the community, showed that 43% of Escherichia coli resistant to many types of antibiotics. The study shows that in Surabaya and Semarang there is a problem of antimicrobial resistance, the use of antibiotics that is unwise, and infection control is not optimal. In the presence, antibiotic amoxicillin in surface water and wastewaters not only affect water quality, but also cause long-term adverse impacts on ecosystems and human health due to its resistance to biodegradation naturally and levels in the range of concentrations ug/L and mg/L in the environment. The standard used for monitoring wastewater are based on the quality standards of wastewater in the Decree of the State Minister for the Environment No.51/MENLH/10/1995 concerning Industrial Liquid Waste Quality Standards and supported by the Republic of Indonesia Minister of Health Regulation Number PERMENKES No. 8 year 2015 concerning the Antimicrobial Resistance Control Program to control antibiotic resistance. The efforts to overcome these problems, has been developed waste treatment techniques such as Fenton reaction, ozonization, photocatalyst, sonification, irradiation or a combination of several types of waste treatment methods. Selection of wastewater treatment to be used depends on the economic value and also the reliability and efficiency of processing. Electrochemical method is one of them, because of increasing efficiency can be achieved and it is easy to operate and control the electrochemical reactor. Electrochemical method also has the following advantages such as can remove and reduce the levels of metal ion, destroy hazardous and mixed wastes that contains organic materials and toxic compounds that can not be treat in a biological process, by anodic oxidation reaction directly or indirectly. In this research, an amoxicillin’s electro-oxidazing which is mediated by Co(III) metal ions is referred to a mediated electrochemical, MEO, and study about the oxidation and reduction reactions of amoxicillin antibiotics with voltammetry methods and electrolysis. Co(III) is a strong oxidizing agent so that it can be used as a mediator, but Co(III) species in water are very quickly reduced to Co(II) because they oxidize water. Therefore, in this study also studied the method of Co(III) preparation by oxidizing Co(II) electrochemically in an electrochemical with single cell using Pt electrodes. Co(III) will also form complex compounds with amoxicillin, so that the electro-oxidation process need to regulated parameter such as the potential and current used, and temperature to provide a good degradation efficiency. Electro-oxidation of amoxicillin using 0.1 M Na2SO4 as a supporting electrolyte solution with three working electrodes was carried out. The working electrodes prepared in this study were Pt, Pt/Co and Pt/Co(OH)2 electrodes. Furthermore, amoxicillin electro-oxidation was carried out using platinum electrodes, Pt/Co(OH)2 and Pt/Co using cyclic voltammetry and electrolysis methods with a constant current of 1200 mA and a potential of 6 V at room temperature. Amoxicillin oxidation using the voltammetry method with three different working electrodes gives an electrocatalytic effect on the surface of the electrode especially on the surface of the Pt/Co electrode is better than on the surface of the Pt/Co(OH)2 electrode and platinum disc electrode. The amoxicillin electro-oxidation mechanism on the Pt disc and Pt/Co(OH)2 electrodes surface is dominated by the diffusion process, while for Pt/Co is dominated by the adsorption process, due to the binding between amoxicillin against cobalt on the pore surface of the platinum electrode modified with cobalt. The pH measurement using cyclic voltammetry, the following results were obtained as follows: 0.0584 V/pH of the working electrode for platinum disc, 0.0592 V/pH for Pt/Co(OH)2 electrode and 0.0606 V/pH for Pt/Co electrode. This shows that the number of electron transfers taking part in the reaction at the electrode surface is equal to one electron. The results of analyte measurements using differential pulse voltammetry (DPV) show that modified electrodes can improve the current response and sensitivity of the electrodes. The calibration curve provides a linear area in the concentration range of 20 - 80 µM, respectively 7.15 µM for Pt disc electrode, 3.64 µM for the Pt/Co(OH)2 electrode and and 8.67 µM for the Pt/Co electrode. The results of measurements on field sample using platinum and modified platinum electrodes showed that the results were not significantly different from the HPLC result at the 95% confidence level. Electro-oxidation of amoxicillin using laboratory-scale electrochemical cells with a volume of 250 mL and an initial concentration of amoxicillin 1000 µM gave satisfactory results, especially for the electro-oxidation process of real samples of amoxicillin waste using Pt/Co anode material mediated by Co(III) with a degradation percentage of 99.03% for 6 hours, 92.35% Pt/Co(OH)2 anode and 76.91% Platinum anode. The presence of cobalt (II) in solution which is oxidized to cobalt (III) which further oxidizes amoxicillin in the electrochemical cell. For application in separate electrochemical cell, the electro-oxidation process gave the percentage of degradation for 6 hours was 20.73% for Pt anode, 31.43% for Pt/Co(OH)2, and 42.83% for Pt/Co. The aims of this study are to provide an alternative antibiotics wastewater treatment and expected to provide information about the process of oxidation that can be applied to an amoxicillin sewage treatment effluent coming from the pharmaceutical or water containing amoxicillin originating from animal livestock farming or hospital wastewater and other organic wastewater in our environment.