A Polyaniline-Based Scale Inhibitor with Enhanced Retention and Exceptional Thermal Properties for Squeeze Treatment at HTHP Conditions

Sulphide scales have low solubility and are mostly observed in deep high temperature/high pressure (HTHP) reservoirs. Particularly, squeeze treatment for HTHP wells in sandstone reservoir, has always been challenging due to the thermal degradation of polymeric scale inhibitors followed by poor retention properties. To this date, identifying a squeezable scale inhibitor for sulphide scale deposition that compiles with these conditions is an ongoing research topic. A thermally stable Polyaniline-Co-Polymer based scale inhibitor (PANI-Co-Polymer SI) has been developed, characterised, and tested. Adsorption isotherms analysis, thermogravimetric analysis (TGA), dynamic tube blocking tests (TBT) and scanning electron microscopy (SEM) analysis have been carried out in order to assess the efficiency against zinc sulphide (ZnS) scale as well as adsorption and desorption properties of the newly formulated product. Based on adsorption isotherms analyses, PANI- Co-Polymer SI shows high adsorption on sand particles that follows the Freundlich adsorption model. Product performance was also evaluated by TBT and TGA. Monitored differential pressure values over a one-hour period, shows a minimum effective dose (MED) of <5mg/L for ZnS and thermal stability up to 385° C, respectively. For a better interpretation of the inhibition mechanism by PANI-Co-Polymer SI, transmission electron microscopy (TEM) images and selected area electron diffraction (SAED) were implemented. Results indicate secondary crystal nucleation and growth disruption for ZnS. These results show that PANI-Co-Polymer SI could be a successful candidate to be used as a squeeze treatment for preventing ZnS scaling issues under HTHP conditions

Fabrication of a Highly Tunable Graphene Oxide Composite through Layer-by-Layer Assembly of Highly Crystalline Polyaniline Nanofibers and Green Corrosion Inhibitors: Complementary Experimental and First-Principles Quantum-Mechanics Modeling Approaches

Three-dimensional graphene oxide (GO) nanosheets were utilized as a unique versatile platform for the fabrication of an effective anticorrosion system through a layer-by-layer (L-<i>b</i>-L) assembly technique. In this way, the highly ordered crystalline polyaniline (Pani) nanofibers and green corrosion inhibitors (GIs) were synthesized. Sustainable corrosion inhibitors were obtained from the extract of <i>Urtica Dioica</i> leaves. The GO-Pani-GI nanosheets were characterized by Fourier transform infrared spectroscopy, high resolution–transmission electron microscopy, field-emission scanning electron microscopy, UV–visible spectroscopy, and thermal gravimetric analysis. In addition, the adsorption features of Pani onto GO sheets and its binding propensity against GIs were assessed by applying first-principles quantum-mechanics (QM) modeling approaches. The anticorrosion properties of the GO-Pani-GI were then examined using electrochemical impedance spectroscopy and polarization test. The results achieved from QM modeling studies demonstrated that the Pani strongly anchored to GO surfaces via physisorption mechanism. Computations further declared that all GIs interacted with Pani through intermolecular H-bonds. Moreover, the experimental investigations revealed the superior anticorrosion performance of multilayered graphene nanocomposites