Use of Chitosan and Chitosan-Magnetite Spheres for Arsenic Groundwater Removal. Factorial Designs as Tools to Calculate the Efficiency of Removal

The lack of access to drinking water is a problem that affects many towns in the Province of Santa Fe. Many people affected by this situation use groundwater for consumption, cooking, and irrigation. In this work, a colorimetric analytical technique is used to quantify arsenic. It is sufficiently sensitive, simple, and economical to apply to the towns of interest. This work synthesized a hybrid sorbent in the form of magnetite-chitosan spheres (M-Q). The sorption capacity of this new sorbent for As removal was 270% greater than that of chitosan spheres (Q), which was 30%. Another advantage of this hybrid sorbent is the capability of being sep-arated by its magnetic properties. The work was done with groundwater (Andino, Province of Santa Fe) with high conductivity (12.1 µS/cm), hardness (1125 mg/L CaCO3), and an As(V) concentration of 265 µg/L. The removal capacity from groundwater was optimized using a composite factorial design, and for the conditions of mass 0.49 g, pH 5.24, and contact time of 81.23 min, it was found to be 81%.