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Article
Prediction of Zinc Consumption as Sacrificial Anode in Cathodic Protection of Steel in Sea Water Using Artificial Neural Network

Author: Aprael S. Yaro
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2008 Volume: 14 Issue: 2 Pages: 2495-2508
Publisher: Baghdad University جامعة بغداد

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Abstract

Corrosion has gained special attention due to its significance, when predicting corrosion rates. However, the complexity and variability makes it hard to model its effects. This study evaluates the usefulness of Artificial Neural Networks (ANN) to predict the corrosion rate as a function of several factors which have been related in previous studies to the protectiveness of low carbon steel in sea water, i.e. Temperature, Flow rate, pH, and time. Results showed that neural networks are a powerful tool and that the validity of the results is closely linked to the amount of data available and the experience and knowledge that accompany the analysis. Statistical analysis showed that the proposed correlation has an Average Absolute Relative Error (AARE) of 0.09% and Standard Deviation (S.D) 0.46%

ان ظاهرة التآكل تكتسب اهميه خاصة عندما يتعلق الأمر بالتنبؤ بمعدلات التآكل. من ناحية ثانية ان التعقيدات و المتغيرات اثناء حدوثها تجعل من الصعب نمذجة تأثيراتها. هذه الدراسه تقيم فوائد شبكة الأعصاب الأصطناعية للتنبؤ بمعدلات تآكل الحديد الكاربوني في عملية الحمايه الكاثودية في ماء البحر و بدلالة عدد من المتغيرات كدرجة الحرارة،سرعة جريان ماء البحر و حامضيته اضافة الى زمن تعرض النموذج للوسط. أظهرت النتائج ان تقنية شبكات الأعصاب الأصطناعيه اداة فعالة و ان صحة النتائج تربط و تعبر بقوة بين كمية النتائج المتوفرة و الخبرة المعرفة المرافقة لتحليل النتائج. التحليل الأحصائي اظهر ان العلاقة المقترحة في هذه الدراسة افرزت معدل الخطأ النسبي المطلق يساوي 0.09% و الأنحراف القياسي يساوي 0.46% .


Article
A Galvanostatic Polarization Investigation of Steel Corrosion in Alkaline Solutions

Author: Aprael S. Yaro
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2008 Volume: 14 Issue: 3 Pages: 2752 -2761
Publisher: Baghdad University جامعة بغداد

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Abstract

The electrochemical behavior of iron and steel in alkaline media is complex,not well understood.It is difficult to determine corrosion rates of steel in high pH solutions by extrapolation of Tafel curves.Polarization resistance (Rp) must be determined in some other way.In this study an attempt was made to find (Rp) values of steel corroding in saturated Ca(OH)2 by anodic currents impressed galvanostatically to the steel from a counter electrode placed together with a reference electrode(I.e. impressed anodic current densities were (10,20,40,and 100µA/Cm2 and duration time was about 25 minutes). It was found that this rapid and non destructive polarization technique yields accepted and reasonable information on corrosion behavior.

التصرف الكهروكيمياوي للحديد والفولاذ في الأوساط القاعدية معقد وليس واضحا بصورة جيدة.من الصعوبة ايجاد معدلات التآكل للحديد في المحاليل القاعدية بطريقة تافل لذلك لا يمكن ايجاد مقاومة الأستقطاب (Rp) ويجب البحث عن طريقة اخرى لأيجادها.في هذه الدراسة جرت محاولة لأيجاد قيم مقاومة الأستقطاب لحديد يتعرض للتآكل في وسط من هيدروكسيد الكالسيوم المشبع و الذي يشبه السمنت في أسه الهيدروجيني (pH>12.5) بتسليط تيارات كلفانية انودية ساكنة على الحديد من القطب المساعد (counter electrode) يرافقه قطب المرجع (reference electrode).(سلطت تيارات بقيم 10,20,40,100 مايكروامبير/سم2)خلال زمن يقارب 25 دقيقة.لوحظ من الدراسة ان استعمال هذه الطريقة افضت الى نتائج مقبولة و معقولة على تصرف تلآكل الحديد.


Article
Evaluation of the Performance of Some Chemical Inhibitors on Corrosion Inhibition of Copper in Acid Media

Authors: Anees Abdullah Khadom --- Aprael S. Yaro
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2008 Volume: 14 Issue: 2 Pages: 2350-2362
Publisher: Baghdad University جامعة بغداد

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Abstract

The inhibition of copper corrosion by Naphthylamine (NA), Ethylenediamine (EDA), Tetraethylenepentamine (TEPA), Diethylenetriamine (DETA), and Phenylenediamine (PDA) in 5% HCl have been investigated by weight loss technique at different temperatures. The results were compared with Benzotriazole (BTA), the common inhibitor used for inhibition of copper corrosion in different environments. The BTA film formed on the copper surface obeys Langmuir Adsorption Isotherm. While NA, EDA, TEPA, and DETA appear to obey the Freundlich Adsorption Isotherm. In the other hand, the two-adsorption isotherms were unsuitable to represent the data of PDA. Results also showed that the Kinetic-Thermodynamic Model was suitable to fit the experimental data of the most inhibitors of the present study.

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Article
Copper Recovery from Spent Etchant Cupric Chloride Solution by Electrowinning Method

Authors: Zuhaira N. Hanna --- Aprael S. Yaro
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2007 Volume: 13 Issue: 2 Pages: 1344-1353
Publisher: Baghdad University جامعة بغداد

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Abstract

Recovery of copper from actual spent etchant cupric chloride solution used in manufacturing of printed circuit board (PCB) containing 124 g/l Cu^+2 ions concentration and 60 g/l hydrochloric acid was investigated in a batch mode jacketed tank. This tank was constructed with inner dimensions of 19×10×15 cm^3. Cylindrical rode-shape titanium was used as cathode, while two rectangular shaped graphite were used as anodes. The parameters studied were: current density (0.16-0.30 A/cm^2), copper concentration in etchant solution (30-124 g/l) and the temperature (25-45 °C). The highest current efficiency obtained was about 92% and the lowest power consumption achieved was about 2.7 W.h/g within the temperature range 25-35 °C.

يهدف البحث الى استعادة النحاس بطريقة الترسيب الالكتروليتي من محلول كلوريد النحاس الفائض (المتخلف) من انتاج البطاقات الالكترونية، يحتوي المحلول على ايونات النحاس بتركيز 124 غملتر و حامض الهيدروكلوريك بتركيز 60 غماتر. تم البحث باستخدام نظام الوجبات في خزان ذو جاكيت لغرض التبريد و بابعاد داخلية 19×10×15 سم^3. استخدم قطب كاثود اسطواني الشكل من التيتانيوم و قطبي الانود مستطيلي الشكل من مادة الكرافيت. درست الظروف التشغيلية التالية: كثافة تيار (0.16-0.30 امبيرسم^2) و تركيز ايونات النحاس بالمحلول (31-124 غملتر) و درجة الحرارة (25-45 5^م). اعلى كفاءة تيار تم الحصول عليها كانت حوالي 92 % و اقل طاقة مستهلكة لترسيب النحاس على سطح الكاثود بالساعة كانت حوالي 2.7 واطزساعةغم ضمن درجة الحرارة 25-35 5^م.


Article
Sacrificial Anode Cathodic Protection of Low Carbon Steel in Sea Water

Authors: Khalid W. Hameed --- Aprael S. Yaro
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2007 Volume: 13 Issue: 3 Pages: 1780-1790
Publisher: Baghdad University جامعة بغداد

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Abstract

Cathodic protection is a corrosion-prevention technique which uses the electrochemical properties of metals to insure that the structure to be protected becomes the cathode of an electrolytic cell.Laboratory evaluation was conducted on zinc electrode as anode material that used for sacrificial anode cathodic protection (SACP)of carbon steel. Rate of zinc consumption during cathodic protection of carbon steel pipeline carrying seawater (4 % w/v NaCl solution) were measured by the loss in weight technique. Variables studied were seawater temperature (0-45o C), flow rate (5-900 lit/h), pH (2-12) and duration time (1-4 h). It was found that the rate of zinc consumption increases with increasing seawater temperature, flow rate and duration time and decreases with pH increase. Under the mentioned operating conditions, the rate of zinc consumption during cathodic protection of steel ranged from 5.65×10-3 to 98.9×10-3 g/cm2.day.For the system under investigation, the cell responsible for cathodic protection is Zn/NaCl/Fe.

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Article
Modelling and Optimization of Carbon Steel Corrosion in CO2 Containing Oilfield Produced Water in Presence of HAc

Authors: Khalid H. Rashid --- Aprael S. Yaro
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2015 Volume: 16 Issue: 2 Pages: 1-8
Publisher: Baghdad University جامعة بغداد

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Abstract

Previously, many empirical models have been used to predict corrosion rates under different CO2 corrosion parameters conditions. Most of these models did not predict the corrosion rate exactly, besides it determined effects of variables by holding some variables constant and changing the values of other variables to obtain the regression model. As a result the experiments will be large and cost too much. In this paper response surface methodology (RSM) was proposed to optimize the experiments and reduce the experimental running. The experiments studied effects of temperature (40 – 60 °C), pH (3-5), acetic acid (HAc) concentration (1000-3000 ppm) and rotation speed (1000-1500 rpm) on CO2 corrosion performance of the regression model calculated by RSM. The experiments were conducted in saturated solution of CO2 with 3.5 % NaCl solution. STATISTICA program version 10 was used for data analysis. In conclusion a quadratic model is proposed to predict the effect of mentioned variables in CO2 environment.


Article
The Inhibition Effect of Peach Juice on Corrosion of Low Carbon Steel in Hydrochloric Acid at Different Temperatures

Authors: Hadeel F. Ibraheem --- Aprael S. Yaro ابرائيل سركيس يارو
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2010 Volume: 11 Issue: 1 Pages: 65-76
Publisher: Baghdad University جامعة بغداد

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Abstract

The corrosion inhibition of low carbon steel in1N HCl solution in the presence of peach juice at temperature (30,40,50,and 60)°C at concentration ( 5, 10, 20, 30, 40and 50 cm3/L)were studied using weight loss and polarization techniques. Results show that the inhibition efficiency was increased with the increase of inhibitor concentration and increased with the increase of temperature up to 50ºC ,above 50ºC (i.e. at 60 ºC) the values of efficiency decreases. Activation parameters of the corrosion process such as activation energies, Ea, activation enthalpies, ∆H, and activation entropies, ∆S, were calculated. The adsorption of inhibitor follows Langmuir isotherm. Maximum inhibition efficiency obtained was a bout 91% at 50ºC in the 50 cm3/L inhibitor concentration. The polarization curves show that peach Juice is a mixed inhibitor


Article
Anodic Polarization of Mild Steel in Saturated Ca(OH)2 Contaminated with NaCL in Presence of NaNO2

Authors: Hany S. Hassan --- Aprael S. Yaro ابرائيل سركيس يارو
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2007 Volume: 8 Issue: 2 Pages: 39-42
Publisher: Baghdad University جامعة بغداد

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Abstract

The corrosion behavior of mild steel in saturated aerated and dc-aerated Ca(OH)2 solution was investigated using electrochemical measurements. The work was carried out with small coupons immersed in soIw ions containing dWèrent quantities of MaC in presence of various NaNO concentrations w corrosion inhibitors. It has been found that:(I) In presence of NaCI the time required to reach °2 evolution potential in dc-aerated Ca(0h9 polarized at lOpA/cm is function of inhibitor concentration and it becomes lass as NaNO increases compared with zero presence indicating the effectiveness of PIaNO as anodic corrosion inhibitor. (2) In absence of NaC1, the time required to reach 01 evolution potential in de solutions is less that in aerated solutions when inhibitor increases from 0 to 0.3 wt%. (3) In presence of sufficient chloride in dc-aerated Ca(OI-i9, solution, the passive film m broken down locally.


Article
Corrosion Inhibition of Aluminum Alloy 5083

Authors: Huda A. Dahyool --- Aprael S. Yaro ابرائيل سركيس يارو
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2009 Volume: 10 Issue: 4 Pages: 19-25
Publisher: Baghdad University جامعة بغداد

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Abstract

The corrosion inhibition of aluminum alloy .5083 by an environment friendly compound called (8- Hydroxyquinoline) in acidic and alkaline solutions ofpH (2 and 12) respectively were studied using weight loss and polariza techniques. Also to examine the main and combined effects of the inhibitor concentration, pH. and contact time using factorial experimental design. Results show that corrosion rate decreased with increasing both inhibitor concentration and contact time and increased with increasing pH value. The polarization curves show that 8-hydroxyquinoline is a cathodic inhibitor


Article
Phenyl Thiourea as Corrosion Inhibitor for Mild Steel in Strong Hydrochloric Acid

Authors: Aprael S. Yaro ابرائيل سركيس يارو --- Dhuha A. Abdulaaima
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2012 Volume: 13 Issue: 2 Pages: 1-9
Publisher: Baghdad University جامعة بغداد

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Abstract

The inhibitive action of Phenyl Thiourea (PTU) on the corrosion of mild steel in strong Hydrochloric acid, HCl, has been investigated by weight loss and potentiostatic polarization. The effect of PTU concentration, HCl concentration, and temperature on corrosion rate of mild steel were verified using 2 levels factorial design and surface response analysis through weight loss approach, while the electrochemical measurements were used to study the behavior of mild steel in 5-7N HCl at temperatures 30, 40 and 50 °C, in absence and presence of PTU. It was verified that all variables and their interaction were statistically significant. The adsorption of (PTU) is found to obey the Langmuir adsorption isotherm. The effect of temperature on the adsorption process showed that the adsorption process is exothermic, spontaneous and represents mixed chemical and physical adsorption for PTU on the metal surface.

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