Removal of triclosan from aqueous solution by activated carbon and nylon 6,6 nanofiber

Abstract

Triclosan (TCS) is one of the biocide that functions as antibacterial and antifungal agent and has the ability to kill and hinder the growth of bacteria. Hence, it is used in many personal care and health care products such as in shampoo, detergent, first aid, deodorant and cosmetics. However, TCS can cause health and environmental problems such as environmental pollutions, carcinogenic impurities, acute toxicity and endocrine disruption. Due to rapid urbanizations and growth populations, TCS was detected in many sewage treatment plants, river, and soil. The conventional system that was used to remove TCS and other pollutants from water used a lot of chemicals, involved a time-consuming procedure and cannot effectively remove all the pollutants from water. Therefore, the effective method to remove TCS with high removal rate in shorter time was studied. The aim of this study was to investigate the removal of TCS from aqueous solution by combining the activated carbon (AC) with nylon 6,6 nanofiber. In this study, AC from coconut pulp waste (Cocos nuciefera) and nylon 6,6 nanofiber were used to remove TCS from aqueous solution. The effects of physico-chemical parameters and physical-chemical characteristics for both AC and nanofiber have been studied to determine the best possible conditions for maximum removal of TCS. The AC was prepared by using coconut pulp waste treated with Zinc Chloride and was carbonized under nitrogen flow at 300 °C for 1 hour. The nylon 6,6 nanofiber [14 wt.%] was prepared by using electrospinning machine with injection rate at 0.4 mL/h, tip-to-collector distance at 15 cm, rotation speed at 1000 rpm and high voltage at 26 kV. The parameters studied for AC and nylon 6,6 nanofiber during the adsorption test were contact time, adsorbent dosage, agitation speed, initial TCS concentration, pH and temperature of the TCS solution. Besides that, the filtration test was done by using flat sheet membrane test machine at pressure 1.0 bar. The characteristics of AC and nylon 6,6 nanofiber were analysed by using Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FTIR) and Brunauer–Emmett–Teller (BET). The experiments show that the adsorption method by using AC can remove 83.3 % of TCS within 20 minutes and the filtration method by using nylon 6,6 can remove 90.2 % TCS within 5 minutes. After combine the adsorption and filtration method of both AC and nylon 6,6 nanofiber, the removal of TCS increased to 100 % removal in less than 5 minutes. For isotherms study, the AC follow Langmuir isotherm and nylon 6,6 nanofiber follow Freundlich isotherm. While for kinetics study, both AC and nylon 6,6 follow pseudo-second-order model. This study proved that the combination of AC and nylon 6,6 nanofiber can increase the removal of TCS in water.