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In this work, we developed cetrimonium bromide (CTAB)‐grafted faujasite nanoparticles (C‐g‐F) as wax inhibitors for the deposits that were formed from a model oil system consisting of 5 wt.% paraffin wax in toluene. Our developed nanomaterials were fully characterized, hydrophobically modified, and their deposition inhibition performance compared with virgin CTAB was investigated in a model waxy oil through cold finger setup (CF), differential scanning calorimetry (DSC), cold flow yield strength, and cross‐polarized microscopy (CPM). Applying our nano‐inhibitors at a concentration of 100 ppm led to more than 50 wt.% inhibition and a 30% reduction of deposit cold yield strength. Interestingly, the presence of FAU nanoparticles in the core structure of C‐g‐F contributed to better dispersibility, enhancing surface wettability (reducing interfacial tension with wax crystals), facilitating inhibitions, and preventing co‐crystallization greater than the surfactant alone. The morphological analysis results showed that C‐g‐F, due to their novel surface features, could suppress the unordered wax crystals from networking, resulting in uniform spherical‐like wax aggregates. Hence, the application of tiny concentrations of C‐g‐F (10 to 300 ppm) outperformed stand‐alone surfactants in nucleating the wax crystals. [ABSTRACT FROM AUTHOR]

Adsorptive phenomena involving dispersed iron oxide superparamagnetic nanoparticles and asphaltenes in crude oil have been profiled as promising technological alternatives, particularly since these interactions can induce significant structural changes within the oil matrices, effectively inhibiting the formation of complex long-range viscoelastic structures. Furthermore, the effect of adsorbed asphaltenes on magnetic dipolar interactions among particles has been proven, showing the formation of multiple asphaltene layers that stimulate a steric repulsive barrier. Despite the discussed hindering phenomena, this research demonstrated the effectiveness of the sequence of physical processes framework to provide intra-cycle structure-rheological interpretations in large amplitude oscillatory shear of a ferrofluid-modified heavy oil, upon the application of an external magnetic field. The analysis proved that disordered nanoparticle/asphaltene aggregates are highly extended and naturally formed in the absence of magnetic forces. In contrast, in the presence of a perpendicular field applied by a controlled rate magneto-rheometer, the formation of interacting structural aggregates of several hundred nanometers was observed, analogous to magnetorheological fluids. These results were validated by adjusting a phenomenological model that effectively represented the intricate processes involved in the formation and reorientation of aggregates, based on the experimental data acquired from zero-field-cooled and field-cooled magnetization curves. This revealed a distinct blocking temperature distribution at around 274 K, which was linked to Brownian relaxation phenomena exhibited by nanoparticle aggregates. In this regard, this research provided a precise extended description of the effect of magnetic fields on the microstructural organization of complex fluids using nonlinear rheology and magnetometry. [ABSTRACT FROM AUTHOR]