Soil is an important and complex environmental compartment and soil contamination contributes to the pollution of aquifers and other water basins. A simple and low-cost experiment is described in which the mobility of three organic compounds in an artificial soil is examined using dry-column flash chromatography. The compounds were applied on top of the soil surface, and the column was irrigated with a dilute solution of calcium chloride that mimics rain. The compounds were detected in column drainage fractions using classic qualitative tests in which the intensity of the color produced is related to the concentration of the analyte. The experiment replicates a leaching system in which organic substances migrate through soil at distinct rates as a result of differences in partition constants and water solubility, properties that are related to structural features.

This work addresses environmental applications of magnetic nanoparticles. We highlight the chemical design of filtration aids based on magnetic nanoferrites coated with specific ligands potentially used in magnetic separation of pollutants from water. From electrochemical measurements, we determined the concentration of the surface sites in function of pH for the precursor magnetic nanoparticles. Then, coupling the speciation diagrams of the precursor nanoferrite particle surface with that of the specific ligand, it was possible to provide a theoretical prediction of the optimal pH for particle surface-ligand complexation, leading to advances in nanosorbents developing.

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An undergraduate chemistry experiment on water pollution remediation is presented. It describes the use of electrocoagulation to remove phosphates from an artificial domestic effluent prepared with cola soft drink, using aluminum foil and aluminum metallic plates as electrodes. Phosphate concentrations in the electrolytic solution were determined by a standard spectrophotometric methodology. Results using the artificial effluent were comparable to those observed in an analogous procedure using a sample of urban domestic effluent. Besides, electrodes constructed with aluminum foil gave similar results to those observed with metallic plates, with the advantage of a lower experimental cost. Millimetric corrosion holes at the aluminum paper anode and adsorption of beverage-colored material on the flocs, formed during electrocoagulation, were easily visible at the end of the process. The experiment presents fundamental chemistry techniques for environmental sanitation issues while introducing students to the aspects of brazilian legislation regarding maximum allowable phosphor concentration in effluents.