Preparation of the core/shell structure of magnetic chitosan particles and application in oilfield

Abstract

Contrary to the traditional surfactants, the novel magnetic NiFe2O4-chitosan nanoparticles have the advantage of excellent biodegradation. The NiFe2O4-chitosan nanoparticles with core-shell structure were prepared. The images of TEM and the SEM exhibited that the cubic-shape magnetic NiFe2O4 particles were encapsulated in the spherical chitosan nanoparticles. Sizes of all NiFe2O4-chitosan nanoparticles were below 100 nm. The saturated magnetization of NiFe2O4-chitosan nanoparticles could reach 75 emu/g and demonstrated the characteristics of superparamagnetism. Evaluation of the interfacial properties of the product indicated that the interfacial tension between crude oil and water could be reduce to ultra-low values (10−3 mN/m) upon the magnetic NiFe2O4-chitosan nanoparticles application in several blocks in Shengli Oilfield without other additives. The magnetic NiFe2O4-chitosan nanoparticles had good salt-resisting capacity.