Remoción de dodecano en suelo mediante el lavado con solución acuosa de tensoactivos sintéticos y biológico

Abstract

The efficiency of three surfactants is compared when a soil polluted with dodecane is washed using each of them in the process. To accomplish this objective, two bulks of soil, where polluted with 20 ml of dodecane/kg and 40 ml of dodecane/kg each. Three micelar solutions (prepared with CTAB, SDS and rhamnolipid), the three at two different concentrations (1 and 3 CMC) are used to wash the polluted soils. The clean (not polluted), polluted and washed soils where analyzed in order to make the comparative between them focalizing on their characteristics to determine the average of remediation that each had after the washings. The characterizations made by soil mechanics, show that the washings made to a soil polluted with 40 ml of dodecane/kg , with SDS had a performance slightly superior to those made by biosurfactant rhamnolipid and CTAB, using a micelar solution of 3 CMC. SDS recovered the soil’s porosity in a 91.9% against 88.7% of the other two. Analyzing these soils by DSC, the quantity of dodecane removed, under the same conditions, is 58.4% for SDS, 60.8% for rhamnolipid and 45.6% for CTAB. FTIR allows a qualitative analysis to what seems the adsorption of CTAB to the soil’s particles, making it a bad alternative for this soil’s remediation. The rhamnolipid is produced microbiologically; therefore it is environmental friendly, being less toxic in the washing of soil as the type used in this work (poorly-graded sand) polluted with dodecane, proving to have efficiency similar to that of SDS of synthetic origin.