Batch adsorption study for the removal of textile dyes from aqueous solutions using pandanus amaryllifolius (RAMPE) leaves

Abstract

With the development of the manufacturing industry in recent days, there are obvious advantages and some disadvantages to human beings. One of the leading disadvantages is environmental pollution. Water pollution continues due to the continual uncontrolled largescale release of dyes to water bodies mainly from the textile industry effluents. These dyes can threaten directly and indirectly human, plant and animal life. This research is focused on removal of selected textile dyes methylene blue, crystal violet, congo red, reactive red and reactive black B via adsorption. The adsorbent was dried leaf powder of flavouring plant Pandanus amaryllifolius, widely famous as ‘rampe’. Rampe leaves powder was chosen as the adsorbent due to its wide availability, simplicity in preparation and mainly due to its ability to remove poisonous substances. Batch adsorption experiments were carried out at room temperature to investigate the adsorption capacity, kinetics of adsorption and equilibrium data. The analytical instrument UV-Visible Spectrophotometer was used to determine the dye concentrations. Batch test results showed that the adsorbent removes Methylene blue, Crystal violet, Congo red up to 95%, 90%, and 81%. However, reactive red and reactive black B dyes did not show significant removal. Kinetic studies showed that the adsorption followed the pseudo-second order kinetic model. According to the intraparticle diffusion model, adsorption happened with two steps for all three dyes. The equilibrium data comply with Langmuir isotherm with maximum adsorption capacities of 38.46, and 20.33 mg g-1 for methylene blue and crystal violet respectively. Congo red complied with Temkin isotherm. FTIR and SEM analysis of the adsorbent before and after adsorption revealed MB, CV, and CR were adsorbed to PALP with chemisorption by creating hydrogen bonds and significant amount of the mass transfer were happened through papillose cells on the leave surface.