الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The corrosion problem is a great problem, which faced the world from the last years until now, we can’t hide this problem from our life but we can reduce “inhibit” it in the metals by several methods as the environment need. It is well known that Carbon steel are the most commonly used construction materials for pipelines in the oil and gas industry. The corrosion and corrosion inhibition of Carbon steel in oil wells formation water become very interesting and important owing to its wide applicability in industry. This work discusses the corrosion of C-steel in Formation water.
This work contains three basic chapters
Chapter one: “INTRODUCTION“
This chapter discusses: corrosion theory, causes of corrosion, forms of corrosion, corrosion migration, types of inhibitors, Literature survey of C-steel corrosion and aim of this study.
Chapter two: ”EXPERIMENTAL AND TECHNIQUES”
Deals with the experimental techniques, which includes the chemical composition of the investigated material, preparation of the used solutions, the instruments, the procedures used for the corrosion measurements.
Chapter three: ”RESULTS AND DISCUSSION”
It deals with the results obtained and their discussion and this chapter is divided into four sections:
Section (A):
The effect of polymer compounds on the cathodic and anodic polarization of C-steel in formation water was investigated. Corrosion rate decreased with increasing of concentration of the polymer compounds together with increase in both cathodic and anodic polarization, but the corrosion inhibition has a great effect on the cathodic polarization. Variation of inhibition efficiency with the structure of polymer compounds was interpreted in terms of the number of adsorption sites in the molecule and their electron charge density, molecular size, mode of adsorption and the polar effect of the substituent groups. The order of increased inhibition efficiency for C-steel corrosion in formation water at all concentrations in the range 50-300 ppm by polarization technique is
AMPS/AM > AMPS/AA > AMPS–Na
Section (B):
The results obtained from (EIS) show that the corrosion reactions in the absence and presence of polymer derivatives proceed under charge transfer control. The increase in concentration of the inhibitors leads to an increase in the value of the charge transfer resistance (Rct) i.e. a decrease of the corrosion rate of C-steel. The double layer capacitance (Cdl) of the corroding C-steel interface decreases with increase in the inhibitor concentration, suggesting an increase of the surface coverage of the inhibitor due to the adsorption of the inhibitor species at the C-steel surface.
The order of decreasing inhibition efficiency for the used compounds is:
AMPS/AM > AMPS/AA > AMPS–Na
Section (C):
The new technique electrochemical frequency modulation (EFM) was used as a rapid and non-destructive technique for corrosion rate measurements. Corrosion current densities (icorr) obtained with this technique were in good agreement with those obtained from Tafel extrapolation technique. In addition of the causality factors were good internal check for verifying the validity of data obtained by this technique.
Section (D):
Scanning electron microscopy (SEM) analysis showed that the inhibition of the polymer compounds were adsorbed on the metal surface forming a thin layer by which metal was protected from corrosion.
In conclusion,
The potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) measurements, electrochemical frequency modulation method (EFM) and SEM analysis support the assumption that corrosion inhibition primarily takes place through adsorption of the polymer compounds on the carbon steel surface.
Agreement among these different independent techniques indicates the validity of the obtained results.
This thesis contains also references, Arabic and English summaries.