Vanconol® ET-101 Corrosion Inhibitor for Oil and Gas Wells

Vanconol® ET-101 Corrosion Inhibitor for Oil and Gas Wells

1.  Product Overview

During oil and gas well production, metal equipment such as wellbore tubing, sucker rods, and production tubing is exposed to high-temperature, high-pressure, and high-salinity production fluids. Corrosive species including CO₂, Cl⁻, dissolved oxygen, and bacteria act synergistically, leading to severe uniform corrosion and localized corrosion that directly compromise production safety and equipment service life.

Vanconol® ET-101 is an alkyl imidazoline adsorption-film corrosion inhibitor specifically developed by our company for downhole oil and gas well service conditions. It rapidly forms a dense protective film on metal surfaces, effectively addressing corrosion caused by CO₂, Cl⁻, and dissolved oxygen, while also helping inhibit under-deposit localized corrosion. The product is non-toxic, environmentally friendly, and heavy-metal-free, making it suitable for a wide range of downhole conditions in both oil and gas wells.

2. 📊 Key Product Parameters

2.1 Physical and Chemical Properties

Property	Specification	Test Method
Appearance (25°C)	Yellow clear liquid, free of suspended matter	Visual inspection
Water solubility	Water-dispersible, no phase separation	GB/T 6324.1
Density d₂₀ (g/cm³)	0.9 – 1.1	GB/T 13378
pH (10% aqueous solution)	≤ 8	SH/T 0069
Kinematic viscosity (mm²/s, 40°C)	< 80	GB/T 265
Pour point (°C)	≤ −20	GB/T 3435
Corrosion inhibition efficiency (electrochemical, %)	≥ 80	GB/T 35509-2017
Corrosion inhibition efficiency (static weight loss, %)	≥ 70	GB/T 35509-2017

Chemical composition: A synergistic blend of alkyl imidazoline corrosion inhibitor + specialty surfactants + enhancer

2.2 Measured Corrosion Inhibition Performance Data

The following data were obtained from third-party laboratory evaluation of oilfield corrosion inhibitors (N80 steel substrate):

Product	Application	Dosage	Test Method	Test Conditions	Inhibition Efficiency	Corrosion Rate	Standard Requirement
ET-101	Oil well	30 ppm	Atmospheric static	Salinity 50,000 mg/L, H₂S-free, 60°C, 7 days	82.53%	5.38 g/(m²·h)	≥ 70% ✅

Key Findings: ET-101 achieved a measured corrosion inhibition efficiency of 82.53% at a dosage of 30 ppm and 60°C, exceeding the standard requirement of ≥ 70%. This test condition represents an H₂S-free oil well scenario, suitable for conventional oil well downhole corrosion protection.

Comparative Measured Data for Vanconol® Corrosion Inhibitor Series:

Product	Application	Dosage	Test Method	Test Conditions	Inhibition Efficiency
ET-101	Oil well	30 ppm	Atmospheric static	Salinity 50,000 mg/L, H₂S-free, 60°C	82.53%
ET-102	Produced water	30 ppm	Atmospheric static	Salinity 62,400 mg/L, CO₂-saturated, 50°C	96.16%
ET-102	Gathering system	200 ppm	High-pressure static	Salinity 62,400 mg/L, CO₂ partial pressure 0.8 MPa, total pressure 2 MPa, 50°C	90.62%
ET-102	Gathering system	200 ppm	High-pressure dynamic	Salinity 62,400 mg/L, CO₂ partial pressure 0.8 MPa, total pressure 4 MPa, 150 rpm, 50°C	96.00%
ET-103	Produced water	30 ppm	Static coupon	Total salinity 62,400 mg/L, 50°C	72.18%

3. 🛠️ Mechanism of Action

The corrosion inhibition mechanism of ET-101 is based on a dual action of chemical adsorption film formation and electrochemical suppression:

3.1 Adsorption Film Formation

The heteroatoms (e.g., N atoms) and metal-anchoring groups within the molecule rapidly adsorb onto active sites on the metal surface via coordinate bonds, forming a dense monomolecular adsorption film. This film exhibits the following characteristics:

• Density: Imidazoline rings align parallel to the metal surface, with intermolecular van der Waals forces promoting close molecular packing

• Selectivity: Preferentially adsorbs on anodic active sites, blocking the anodic dissolution process (Fe → Fe²⁺ + 2e⁻)

• Stability: Maintains adsorption strength under high-temperature (≥ 60°C) and high-salinity conditions, with minimal desorption

3.2 Electrochemical Suppression

The adsorption film simultaneously affects both cathodic and anodic processes of corrosion electrochemistry:

• Cathodic suppression: Reduces the diffusion rate of H⁺ toward the metal surface, slowing the cathodic hydrogen evolution reaction (2H⁺ + 2e⁻ → H₂↑)

• Anodic suppression: Blocks direct contact between corrosive species (Cl⁻, CO₂) and the metal surface, inhibiting anodic dissolution

• Synergistic effect: Specialty surfactants lower interfacial tension, while enhancers reinforce the stability of the adsorption film under high-temperature, high-salinity conditions

3.3 Measured Data and Mechanism Correlation

Test Conditions	Measured Efficiency	Mechanism Interpretation
Atmospheric static, 60°C, 30 ppm, H₂S-free	82.53%	At elevated temperature of 60°C, imidazoline molecules retain effective adsorption, achieving an inhibition efficiency 12.5 percentage points above the standard requirement

4. 📋 Application Guide

4.1 Suitable Application Scenarios

Scenario	Typical Conditions	Suitability
Oil well downhole	Salinity ≤ 50,000 mg/L, CO₂ environment, H₂S-free, temperature ≤ 80°C	✅ Recommended
Gas well downhole	CO₂-dominant, relatively high temperature	✅ Suitable (simulation testing recommended)
Surface gathering lines	CO₂/H₂S co-existence, salinity ≤ 80,000 mg/L	⚠️ ET-102 recommended (dedicated surface gathering formulation)
Produced water treatment	High salinity, scaling tendency	⚠️ ET-103 recommended (combined scale/corrosion inhibition)

4.2 Differentiated Positioning vs. ET-102 / ET-103

Comparison Dimension	ET-101 (Oil & Gas Well Corrosion Inhibitor)	ET-102 (Surface Gathering Corrosion Inhibitor)	ET-103 (Produced Water Scale/Corrosion Inhibitor)
Application Scenario	Downhole wellbore / sucker rod / tubing	Surface gathering lines / stations	Produced water treatment / reinjection
Core Function	Pure corrosion inhibition (downhole high-temperature)	Pure corrosion inhibition (surface gathering)	Integrated scale inhibition + corrosion inhibition
H₂S Adaptability	For H₂S-free oil wells	Handles H₂S/CO₂ co-existence	Handles H₂S/CO₂ co-existence
Measured Efficiency (30 ppm)	82.53% (60°C, salinity 50,000 mg/L)	96.16% (50°C, CO₂-saturated)	72.18% (50°C, salinity 62,400 mg/L)
Scale Inhibition	None	None	Scale inhibition efficiency ≥ 90%
Pour Point	≤ −20°C (superior low-temperature flow)	≤ −10°C	≤ −10°C

Product Selection Guide:

– Downhole oil wells (H₂S-free) →ET-101

– Surface gathering (H₂S/CO₂ co-existence) →ET-102

– Produced water treatment (corrosion + scaling combined) →ET-103

4.3 Recommended Dosage

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Operating Conditions	Recommended Dosage	Remarks
Conventional oil wells (temperature ≤ 65°C)	≥ 15 ppm	Based on produced water volume
High-temperature oil wells (temperature > 65°C)