Modifying a Cuban bentonite and its application as oil adsorbent

Abstract

Inappropriate materials and hazardous waste management has caused a serious problem of pollution of soils all around the world. In Cuba, the oil industry has had a negative impact on environmental issues. The aim on this work is the structural modification of bentonite extracted from a cuban clayfield, in order to obtain a material with adsorbent properties to be apply in oils spilling situations. Ni(II) exchange capacity of the modified clay was determined as a preliminary test using atomic absorption technic. The same procedure was applied using two organic compounds: tetrabutylammonium iodine and hexamethylenetetramine. These materials were characterized by FTIR spectroscopy, and their surface properties were determined at liquid nitrogen temperature by BET method. Laboratory scale tests were conducted to determine their adsorption capacity, according to ASTM method for a type II absorbent. Finely, the obtained materials were tested in front of soils, contaminated with two types of oils (light and heavy). Three different doses of adsorbent clays were used. Best results were obtained for organicpolyoxycation-modified bentonites in front of heavy oil. The average adsorption capacity of these materials is acceptable in all cases, compared with some commercial products with similar structure.