ABSTRACT Industrial activities, inadequate waste disposal, and poor control of discharges generated by mining and domestic activities are the primary causes of water pollution with numerous chemical substances, including heavy metals. Several methods have been proposed for removing metals from water, such as precipitation, membrane separation, ion exchange, solid phase extraction, flocculation, and others to address this issue. The metal bio-adsorption using biomass from crops is an alternative that has shown excellent results in recent years. In this work, We studied the bio-adsorption of five metals present in water on biomass from ground banana peel. We evaluated the retention capacity of copper, lead, cadmium, zinc, and mercury on the bio-adsorbent material subjected to acid hydrolysis, basic hydrolysis, and the material without treatment. The material with the best-obtained results was selected to execute a 2k experimental design. The factors were pH, adsorbent dose, and contact time between the adsorbent and the metal ion solution. We used the anodic stripping square wave voltammetry for the mercury determination and adsorptive stripping by square wave voltammetry for copper, zinc, cadmium, and lead quantification. The maximum adsorption capacity ranged from 20 to 30 mg for each gram of material used for the five studied metals. The optimum pH value for mercury was 3.0 while for copper, zinc, cadmium, and lead was 5.0. The optimum contact time was 15 minutes. Mercury is captured differently from the other metals. The materials were characterized using the techniques of Infrared Spectroscopy, Scanning Electron Microscopy, energy-dispersive X-ray Spectroscopy, and thermogravimetric analysis.
SAMBONÍ-IMBACHÍ et al. (Mon,) studied this question.