Enhancement corrosion resistance of mild steel in 15% HCl solution by a novel bio-based polyurethane for oil well acidizing

Synergistic effect of Canarium strictum leaves extract and KI on the corrosion protection of mild steel in 15% HCl solution

The inhibitory potential of an alcoholic extract derived from Canarium strictum leaves (CSL) was evaluated as a corrosion inhibitor for mild steel (MS) in 15% HCl solution. Furthermore, to enhance its inhibition effectiveness, the influence of potassium iodide (KI) was also examined. The corrosion inhibition and adsorption characteristics of CSL were comprehensively analysed through weight loss measurement, electrochemical impedance measurement (EIS), potentiodynamic polarization (PP), UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS). The effect of temperature and immersion time on corrosion inhibition was also investigated. The studied CSL extract exhibited maximum inhibition efficiency of 92.2% at 700 ppm alone, while adding 5 ppm KI 96.8% inhibition efficiency was observed. Moreover, with KI, an efficiency of 98% was observed at extended immersion of 48 h. The PP results showed that CSL and CSL + KI were good mixed-type inhibitor system. Adsorption data was best fitted to the Langmuir isotherm model, and thermodynamic, kinetic, and surface analyses shed light on the inhibitory mechanism.

Corrosion Inhibition of Carbon Steel in a Sour (H2S) Environment by an Acryloyl-Based Polymer

Corrosion poses safety and operational challenges in the oil and gas field, particularly in a sour environment. Corrosion inhibitors (CIs) are thus employed to protect the integrity of industrial assets. However, CIs have the potential to dramatically impair the effectiveness of other co-additives, such as kinetic hydrate inhibitors (KHIs). Here, we propose an acryloyl-based copolymer, previously used as a KHI, as an effective CI. The copolymer formulation provided a corrosion inhibition efficiency of up to 90% in a gas production environment, implying that it can reduce or even eliminate the need for an additional dedicated CI in the system. It also demonstrated a corrosion inhibition efficiency of up to 60% under field-simulated conditions for a wet sour crude processing environment. Molecular modeling suggests that the enhanced corrosion protection is imparted by the favorable interaction of the heteroatoms of the copolymer with the steel surface, potentially displacing adhered water molecules. All in all, we show that an acryloyl-based copolymer with dual functionalities can potentially overcome issues caused by incompatibilities in a sour environment, resulting in significant cost savings and operational ease.