Organofilization of Smectite Clay from Pedra Lavrada, PB, with Nonionic Surfactant

The petroleum industry has been investing for many years in the use of smectite as dispersant agent in the composition of oil-based and water-based fluids for drilling oil wells. The State of Paraíba is one of the largest producers of such clays and new deposits have been recently discovered in the regions of Cubati and Pedra Lavrada, causing many expectations for the expansion of the national mineral production. The objective of the present work is the organofilization of smectite clay from Pedra Lavrada, PB, through the addition of nonionic surfactant. After organofilization, the clay was characterized through X-ray diffraction and Foster swelling, so that the most suitable surfactant could be chosen for diesel as organic dispersant media. The results show that the incorporation of the surfactant used with the clay caused a significant increase in the interlamellar distance, and that the dispersions presented rheological properties that meet Petrobras' specifications for the use of organoclays in non aqueous based drilling fluids. Keywords: Smectite, drilling fluids, organofilization.