Corrosion is a major cause of the loss of hermeticity in oil and gas pipelines. Corrosion defects affect the remaining life of in-service pipelines and can lead to failures, ruptures, hydrocarbon leakage, product loss, interruptions, environmental damage, economic losses, or, in the worst cases, fatalities. The existence of localized corrosion defects is a significant issue in pipeline integrity analysis, mainly because these structures are commonly buried and cover large extensions, amounting to hundreds or even thousands of miles; thus, it is difficult to size and locate all minor but possibly deep defects. Consequently, probabilistic and statistical modeling methods have been widely used to assess the integrity of corroded pipelines. Statistical modeling methods used to estimate the remaining life of the pipeline have focused on three main aspects: applications to estimate the defect depths and rates of corrosion, Bayesian applications in pipeline integrity to update the probability distribution for corrosion defects (depth, length, and spatial distribution), and pipeline reliability estimations. This paper reviews several methods proposed in the literature for these issues as well as their applications in real life. In addition, some of the present and future challenges related to preventing corrosion in the oil and gas pipeline industry are described.

This paper reports a novel coating containing activated TiO₂ for improving corrosion resistance of Cu. In this study, three types of coatings were compared: one made from GPTMS (3-Glycidopropyltrimethoxysilane) (GC1), and two hybrid sol-gel coatings derived from G1 (solution organic) and activated with titanium. The Class I (GC2) coatings contained crystallized TiO₂ particles integrated into the matrix, while the Class II (GC3) coatings used the liquid precursor TTIP (titanium (IV) isopropoxide). The three coatings, with thicknesses of 0.777 ± 0.5 μm (GC1), 2.054 ± 0.5 μm (GC2), and 3.774 ± 0.23 μm (GC3), were analyzed using XRD, optical profilometry, and SEM techniques. GC1 and GC3 exhibited uniform structures, while GC2 showed cracks due to TiO₂ particles. After salt spray exposure per ASTM B117, the coatings were labeled GCE1, GCE2, and GCE3 for evaluation. Salt spray exposure caused SiO₂ precipitates, impacting coating performance. GC3, with TTIP, showed a uniform surface and controlled roughness, leading to superior corrosion resistance (95% efficiency, 2764 Ω), outperforming GC2 (94% efficiency, 1331 Ω) and the substrate (918 Ω). TTIP improved adhesion and barrier formation, while TiO₂ coatings (GC1, GC2) had increased roughness due to particle irregularities. GC3’s thicker, well-integrated structure contributed to its enhanced performance in corrosive environments.

Y2O3 gels co-doped with lanthanide ions (Ln3+) were synthesized based on the sol-gel process. Eu3+ was used in proportions of 2, 4, and 8 mol% and Tb3+ at a low and constant concentration of 0.075 mol% (Y2O3:Eu3+;Tb3+). The gels were subjected to supercritical drying (aerogel) at 73 bar and 34 °C and to thermal treatment at 800 °C to obtain crystalline materials (crystallized aerogels). Subsequently, each sample was sensitized in a novel way with 9 µmol of the compound 2-thenoyltrifluoroacetone (TTA) -- Y2O3:Eu3+;Tb3+/TTA, to provide an antenna effect in order to focus the morphological, structural-chemical, and luminescent changes assigned to the energy transitions of Eu3+. When the crystal structure by X-ray diffraction (XRD) and the morphology by scanning electron microscopy (SEM) were analyzed, no drastic changes due to functionalization were observed. However, infrared (IR) and Raman spectroscopies were performed to identify the rare-earth oxides vibrational modes, although its main function was to reveal the adhesion of TTA to materials. The excitation-emission spectra were studied to evaluate the energy transfer to the Eu3+ activator ion and the influence of both the Tb3+ sensitizer and the TTA ligand on the luminescent properties of the samples Y2O3:Eu3+;Tb3+ and Y2O3:Eu3+;Tb3+/TTA, also the quantum yield corresponding to the highest luminescence samples was calculated. Based on the results, this class of materials can have novel and useful applications when TTA functionalization is fully exploited.

Corrosion caused by the mixture CO2/H2S in the transport of hydrocarbons is one of the most important research areas in the energy industry due to the severe problems it produces during the wear and tear of the pipes. Based in previous studies, in the present investigation the corrosion of API 5L X-70 steel in media with CO2 and H2S is studied as well as mixtures of both media, by means of a rotating cylindrical electrode due to the need to know the behavior of corrosion products in metals. The corrosion rate is evaluated at different pressures of H2S and CO2 and at 30 and 60°C using the polarization resistance (PR) technique. From the results, it is observed that steel at the conditions of 0.8 bar H2S + 0.2 bar CO2 at 30°C, yielded the lowest corrosion rate. This behavior is attributed to the fact that when H2S predominates it allows the formation of a greater number of protective layers comprised by a mixture of oxides, sulfides, sulfates and carbonates as corrosion products