Chemical modification of cobalt ferrite nanoparticles with possible application as asphaltene flocculant agent

Abstract

Asphaltenes can cause enormous losses in the oil industry, because they are soluble only in aromatic solvents. Therefore, they must be removed from the petroleum before it is refined, using flocculant agents. Aiming to find new materials that can work as flocculant agents to asphaltenes, cobalt ferrite nanoparticles were chemically modified through acid-base reactions using dodecylbenzene sulfonic acid (DBSA) to increase their lipophilicity. Nanoparticle synthesis was performed using the co-precipitation method followed by annealing of these nanoparticles, aiming to change the structural phase. Modified and unmodified nanoparticles were tested by FTIR-ATR, XRD and TGA/DTA. In addition, precipitation onset of the asphaltenes was performed using modified and unmodified nanoparticles. These tests showed that modified nanoparticles have a potential application as flocculant agents used to remove asphaltenes before oil refining, since the presence of nanoparticles promotes the asphaltene precipitation onset with the addition of a small amount of non-solvent.

Controlled deposition of magnetic particles within the 3-D template of wood: making use of the natural hierarchical structure of wood

“…Cobalt ferrite particles have diffraction peaks corresponding to the spinel structure of an orthorhombic cell with values of 2q at 30.3 , 35.6 , 53.3 and 62.9 , corresponding to crystal planes (220), (311), (422) and (440). 33 There appeared to be no difference in the main peaks of the crystal structure of the magnetic particles in comparison to those that deposited in the modied wood samples, indicating that the constrained environment of particle formation in the wood did not affect the type of crystal growth. Due to this lack of a difference in the crystal structure of the particles that deposited in the wood structure versus freely in solution, only the cobalt ferrite system is shown as an example.…”

Synthesis, Characterization and Drug Delivery Profile of Magnetic PLGA‐PEG‐PLGA/Maghemite Nanocomposite

“…[2,19,23] Moreover, these nanoparticles have a crystallite size (Lc) equal to 12 AE 1 nm, determined by the Scherrer equation [24] using the peak corresponding to the (311) crystal plane. [19,25,26] The diffractogram of PLGA-PEG-PLGA copolymer, shown in Figure 3(b) presents only amorphous halos, mainly due to the presence of the small amount of the PEG, equal to 3.5% of the total mass. The diffraction of the sample BC-CTZ, shown in Figure 3 (c) presents the amorphous halo from the copolymer and the crystalline peaks from the drug cotrimoxazole, located at 2u equal to 12 .…”

Petroleum Sorbers Based on Renewable Alkyd Resin and Lignin

“…These peaks correspond to the (220), (311), (400), (422), (511) and (440) crystalline planes in an orthorhombic cell of the cubic spinel structure, respectively. [2,30] The XRD of the composites also showed the main peaks of the magnetic particles. In turn, the composite filled with lignin presented a new broad scattering center at 23.21 , which corresponds to the hardwoods fractions of lignin.…”