Improving the physicochemical properties of Brazilian onshore and offshore crude oils using the production of blends

Use of the Comprehensive Two-Dimensional Gas Chromatography (GC×GC-qMS) to Characterize The Classes of Saturated Compounds in Brazilian crude Oils

“…On the other hand, Oil 7, the lightest oil, showed the highest content in saturated compounds and the lowest content in polar compounds, satisfying the general rule. 13 Its high pour point (6 °C with API gravity of 34.46), however, was not an expected result for a light oil, 13 but the result can be explained by the higher amount of heavy n-paraffins (C27 -C35) when compared the other oils studied (except for Oils 5 and 6 with no content of nparaffins) (Figure 2), as well as the larger amount of iso-paraffins ( Figure 3).…”

“…4 The study oils were classified as light (Oil 7, with API gravity greater than 31), intermediate (Oils 1, 2, 3, 4 and 8, with API gravity between 31 and 22), and heavy (Oils 5 and 6, with API gravity less than 22). 19 Heavy crude oils typically have higher content of polar compounds (resins and asphaltenes) in their composition, while light oils (greater than 31 and high API gravity) show higher content of saturated compounds. 20 In general, all oils analyzed had a relative percentage of polar compounds ranging from 8% to 13% (Table 1).…”

“…Brazilian crude oils with different physicochemical properties, ranging from light to heavy oil, were used in this study. During the oil treatment process, the free water (non-emulsified water) present in oil was separated by decantation for 1 h, as described by Sad et al 13 After that, the water content was determined in the water-in-oil emulsions. Samples with water content more than 2 %v/v were dehydrated.…”

“…18 The crude oil (200 mg) was dissolved in n-hexane and then adsorbed onto the surface of activated silica gel (230 to 400 mesh; SiliCycle® Inc., Quebec, Canada). 13 Particle sizes of 230 to 400 mesh (10 g), 100-200 mesh (5 g) and 70-30 mesh (5 g) were activated at 120 °C for 12 hours and poured into a glass column (250 x 18 mm). The oil adsorbed on silica gel (oil adsorbate) was transferred to the top of the column and successively eluted with n-hexane (200 ml), nhexane: dichloromethane 200 ml (1:1, v/v) and methanol (200 ml) to obtain saturated, aromatic and polar fractions, respectively.…”

Study of the Corrosive Behavior of the AISI 1020 Steel in Acid Crude Oil by Microscopic Techniques (LM, AFM and SEM/EDX) and Raman Spectroscopy

“…The naphthenic acidity and the degree of corrosivity of the petroleum are usually evaluated by the total acid number (TAN) measurements, which corresponds to the amount of KOH (in mg) required to neutralize 1 g of petroleum or its fraction. 7,8 A corrosion mechanism is proposed by equations 1, 2 and 3, in which the iron naphthenate is one of the corrosion products, being soluble in the crude oil, and thus, cannot protect against a continue corrosive process (equation 1). The naphthenic corrosion can also be associated with the H 2 S (equations 2 and 3), which is responsible for the reconstitution of naphthenic acids, due to its attack on the iron naphthenate, turning the process autocatalytic (equation 3).…”