Black tea waste as natural and eco-friendly adsorbent for methylene blue dye removal

Dyes are used extensively in many industries making the research on colour production more important. Despite that, dyes are important class of pollutant in which it is disposed in water resources and causes major environmental problems due to toxicity and carcinogenic property of dye. However, the dispose of dye into the environment can be treated by several alternatives. Agricultural waste is one of the alternative that is widely used for being a potential adsorbent in dyes removal. Researches and studies has been made and found out that the used of tea waste as adsorbent in the removal of MB dye proved to be more economical compared to other dye removal methods as the method of production is relatively easy. In this study, BTW activated carbon and raw BTW was investigated by comparing both samples using various parameters which were contact time, different concentrations, adsorbent dosage and pH to determine the optimum conditions and effectiveness of the adsorbent. The calibration curve of methylene blue dye was plotted. From the results obtained for BTW activated carbon, the optimum contact time was 50 minutes with the percentage removal of 97.95%, the optimum MB concentrations was 20 mg/L with percentage removal of 96.88%, the optimum adsorbent dosage was 0.8 g with percentage removal of 98.23% whereas the optimum pH of the solution was pH 9 with percentage removal of 99.88%. From the results obtained for raw BTW, the optimum contact time was 50 minutes with percentage removal of 97.23%, the optimum MB concentrations was 20 mg/L with percentage removal of 97.73%, the optimum adsorbent dosage was 0.8 g with percentage removal of 97.30% and for optimum pH of the solution there was no optimum point reached. The experimental data were analysed using percentage removal and efficiency of BTW activated carbon and raw BTW. Based on the study that has been made, BTW activated carbon has the potential to remove and adsorb MB dye that cause environmental problems and health effectively was proven.