Natural treatments for the removal of heavy metals and turbidity in the Pativilca river, Peru

Abstract

Objective: To determine the effect of natural and conventional treatments on removing turbidity, heavy metals, andcomplementary parameters of the Pativilca River water. Methodology: A pre-sampling was conducted to select a stretch of theriver with high concentrations of metals, followed by sampling at the identified point (EM.RPATI-I). Six treatments wereevaluated in each sample: two natural (powdered prickly pear mucilage and activated carbon from lignocellulosic fibre of pricklypear), two conventional (conventional activated carbon and aluminium sulfate), and two mixtures (powdered prickly pearmucilage plus prickly pear activated carbon and aluminium sulfate plus conventional activated carbon). The doses used were 0.7mg/L, 10 g/L, 0.1 g/L, and their combinations. The study was conducted over 150 days analysing the variables: turbidity, leadconcentration, iron concentration, pH, electrical conductivity, total dissolved solids, and water temperature. Results: The mosteffective treatments for turbidity removal were prickly pear activated carbon (98.79%), aluminium sulfate (98.72%), andconventional activated carbon (98.47%); for lead removal, they were aluminium sulfate plus activated carbon (94.89%) andconventional activated carbon (94.15%); and for iron removal, prickly pear activated carbon (73.67%) showed the best efficacy.Conclusion: The mucilage and lignocellulosic fiber from prickly pear, as a flocculant and activated carbon, showed a similareffect (p < 0.05) to that of conventional treatments in improving the water quality of the Pativilca River.