Show: 25 50 75 100 Results

Search results: 25 out of 1,020

فعالية عامل مساعد محضر ومحفز بمعادن مختلفة لعملية ازالة الكبريت بالهدرجة لزيت الغاز العراقي == Activity of A Prepared Catalyst Promoted By Different Metals For The Hydrodesulfurization of Iraqi Gas Oil

Author name: طارق محمد نايف
Supervisor name: Abdul | Halim A.K. Mohammed | Hussein K. Hussein
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Doctorate
University: University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: The present work deals with the improvement of Iraqi gas oil containing 1.402 wt. % sulfur by hydrotreating process using different prepared hydrodesulfurization catalysts (Ni - Mo/? - Al2O3, Co - Mo/? - Al2O3, Co - Ni - Mo/? - Al2O3, Ti - Ni - Mo/? - Al2O3 and Re - Ni - Mo/? - Al2O3). All catalysts were prepared under vacuum impregnation to ensure efficient precipitation of metals within the carrier ? - Al2O3. Physical adsorption by nitrogen was investigated, and used for determination of the surface area and pore size distribution of prepared catalysts.The results showed that modified catalysts Ti - Ni - Mo/? - Al2O3 and Re - Ni - Mo/? - Al2O3 have a high surface area 225.1 and 235.23 m2/g respectively, as compered with conventional prepared catalysts Ni - Mo/? - Al2O3 and Co - Mo/? - Al2O3 which their have surface area 178.5 and 191.4 m2/g respectively, and exhibits behavior of type four according to Brunauer, Emmett and Teller (BET) classification, and type H1 according to de Boer classification for hysteresis loop, so, it was concluded that the pores of these catalysts are cylindrical. The performances of all the synthesized catalysts for removal of sulfur and aromatic saturation gas oil were tested at different LHSV (1 to 4 h - 1), temperatures ( 275 to 350 °C), constant pressure 40 bar, and H2/HC ratio 500 ml/ml. The results showed that the sulfur and aromatic content were decresed at all operating conditions for all prepared catalysts. It was found that the sulfur removal from gas oil increases with temperature and decreasing with the space velocity, and the temperature has higher effect on the process of sulfur removal than the space velocity. It was found also that Ni - Mo/? - Al2O3 catalyst is slightly better in sulfur removal (61.5 wt. % ) with than Co - Mo/? - Al2O3 (59.2 wt. %) at the same operation conditions (350 °C and LHSV 1 h - 1), and hydrodesulfurization over Ni - Mo/Al2O3 was improved remarkly by adding Ti and Re promoters. Maximam sulfur removal was 76.81 wt. % using Re - Ni - Mo/? - Al2O3 at temperature 350?C, LHSV 1 h - 1, while minumum aromatic content value is 15.44 wt. % for Ni - Mo/ ? - Al2O3. Calculations showed that the hydrodesulfurization rate expressions fitted with second order reaction kinetics model.The rate constant varied from 0.005 to 0.144 liter/kg.h and the values of activation energy varied from 50.0 to 93.59 kJ/mole for all prepared catalysts. Thiele modulus, for all prepared catalysts was calculated.The lower values of the Thiele modulus (> 0.4) gives strong evidence of negligible pore diffusion limitation.

ازالة المحتوى الكبريتي من وقود الديزل بواسطة الاكسدة والاستخلاص بالمذيب == Desulfurization of Diesel Fuel By Oxidation And Solvent Extraction

Author name: شيم بهجت عبد الكريم
Supervisor name: ودود طاهر محمد | رغد فريد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: يهدف البحث الى ازالة المحتوى الكبريتي من مقطع الديزل المهدرج للتخلص من المركبات الكبريتية الثايوفينية التي تتعذر ازالتها بواسطة عملية الهدرجة المعتمدة في المصافي النفطية. ودراسة افضل الظروف للحصول على اعلى نسبة ازالة.رست الظروف التشغيلية التالية : سرعة ال | Removal of sulfur species from fuels is an increasingly critical environmental issue. Hydrodesulfurization (HDS) removes sulfur compounds, such as mercaptans and sulfides from hydrocarbons; however, some sulfur - containing compounds (such as diebenzothiophene) are very difficult to remove and need deep desulfurization processes.This work was applied to the desulfurized diesel fuel produced from the conventional HDS process for ultra - desulfurization. The used fuel types in this investigation were either real diesel fuel or simulated diesel fuel, where sulfur - containing compound ( dibenzothiophene DBT) converted to its corresponding sulfone by oxidation using hydrogen peroxide as an oxidant and acetic acid as homogenous catalyst, and solvent extraction by using acetonitrile (ACN) or N - methyl - 2 - pyrrolidone (NMP) as extractants.Simulated diesel fuel according to British Petroleum 200B doped with dibenzothiophene (DBT) was prepared, the effect of stirring speed (150, 250, 350 and 450) rpm, temperature (30, 40, 45 and 50) ?C, oxidant/simulated diesel fuel ratio (0.5, 0.75,1 and 1.5) (v/v), catalyst/oxidant ratio (0.125, 0.25, 0.5 and 0.75) (v/v), solvent type, and solvent/simulated diesel fuel ratio (0.5, 0.6, 0.75 and 1) (v/v) were examined in order to obtain the maximum sulfur removal. The results of this work exhibit that the highest removal of sulfur 98.5% for N - methyl - 2 - pyrrolidone and 95.8% for acetonitrile were obtained under the conditions of operating in table below : Stirring Speed (rpm) 350 Temperature (?C) 50 Oxidant (hydrogen peroxide)/simulated diesel fuel ratio 1 Catalyst (acetic acid)/oxidant ratio 0.5 Solvent (ACN or NMP)/simulated diesel fuel ratio 1 Experiments with the above best conditions were carried out on Real diesel fuel obtained from Al - Dora refinery with 1000 ppm sulfur containing compounds. It was found that sulfur removal from real diesel fuel was 62.5% for acetonitrile and 75% for N - methyl - 2 - pyrrolidone.

تطبيقات الطرق العددية في التاكل الكلفاني للمعادن المزدوجة == Applications of Numerical Methods In Galvanic Corrosion of Coupled Metals

Author name: بسمة محمد كاظم الشاهر
Supervisor name: جمال مانع علي الربيعي
General topic: Chemical Engineering
Specific topic: Industrial Processes
Degree: Master
University: University of Technology - Department Of Chemical Engineering - Chemical Process Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: تم دراسة سلوك تاكل معادن النحاس والكربون الصلب والزنك في تراكيز مختلفة من حامض الهيدروكلوريكHCl) ) (0.025، 0.05 و0.075 مولاري ) عند درجات حرارة مختلفة (30، 40 و50 درجة مئوية) باستخدام القياسات الكهروكيميائية (Electrochemical Measurements) في حالة المعا | The corrosion behaviors of metals Copper, Carbon Steel and Zinc in a different concentrations of HCl acid (0.025, 0.05 and 0.075M) at different temperatures (30, 40 and 50°C) were investigated using electrochemical measurements in couple and single state.The galvanic behaviors of coupled metals (Cu - Fe),( Cu - Zn) and (Fe - Zn)were studied using Zero Resistance Ammeter (ZRA) technique, it has been used to measure the galvanic current (Ig) and galvanic potential (Eg) with time. The galvanic corrosion cells for all couples have equal areas of anode and cathode (2×2cm).The galvanic current density (ig) is increased with increasing solution concentration and temperature. The galvanic potential (Eg) is shifted to less negative with increasing solution concentration and temperature and it is close to the corrosion potential of the anode in the couple conditions.The potentiostatic polarization behavior of single three metals (Copper, Carbon Steel and Zinc) in different concentrations of dilute HCl acid (0.025, 0.05 and 0.075M) at temperature (40°C) is found under activation control. The corrosion current density is increases with increasing solution concentration and gives the following arrangement of metals : Cu> Fe > Zn A numerical analysis of galvanic corrosion was presented. The analysis was based on three numerical methods as the boundary element method (BEM), the finite element method (FEM) and the finite difference method (FDM).The potential and current density distributions on the galvanic elements are described by the Laplace equation. The Laplace equation was solved numerically, to determine the potential, current density, and corrosion caused by the galvanic cell using designed computer programs in MATLAB R2014a. The experimentally determined polarization curves have been used in order to define the nonlinear boundary conditions. This boundary value problem has been solved using Newton - Raphson iterative numerical procedure. For the three couple systems (Cu - Fe, Fe - Zn and Cu - Zn), the results obtained for galvanic potential and current density, using the numerical methods (BEM, FEM and FDM) with the overall deviations are 6.689, 10.818 and 18.846 respectively for galvanic current density and 0.631, 1.210 and 1.787 respectively for galvanic potential. From these results it can conclude that the galvanic current density and galvanic potential distribution calculated from the BEM model was in good agreement with the experimental measurements. These are because the main advantages of the BEM over the Finite Element Method (FEM) and the finite difference method (FDM) are high accuracy, discretization on the boundary only which results in a very small number of unknowns, easy dealing with non - regular boundaries and openings that only the domain boundary of interest is required to be discrete, also BEM needs fewer equations and a smaller matrix size than FEM and can solve both finite and infinite domain problems.

استخلاص الزيوت العطرية من قشور الحمضيات باستعمال التقطير البخاري بمساعدة المايكرويف == Extraction of Essential Oils From Citrus By - Products Using Microwave Steam Distillation

Author name: سارة جبير صالح
Supervisor name: ابتهال كريم شاكر
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: يهدف هذا البحث الى استخلاص الزيت العطري من ثلاثة انواع من قشور الحمضيات (البرتقال, الليمون, اللالنكي) بطريقتين : التقطير البخاري والتقطير البخاري بمساعدة المايكرويف.ودراسة تاثير عوامل الاستخلاص : (وزن القشور, وقت الاستخلاص,طاقة المايكرويف ونوع قشور الحمضي | The main objectives of this research is to extract essential oil from : orange( citrus sinensis), lemon( citrus limon) and mandarin( citrus reticulata) peels by two methods : steam distillation (SD) and microwave assisted steam distillation (MASD), study the effect of extraction conditions : weight of the sample( 398.56g, 281.8g, 116.76g), extraction time, microwave power( 135W, 265W, 445W) and citrus peel type( orange, lemon, mandarin) on oil yield and compare the results of the two methods, the resulting essential oil was analyzed by Gas Chromatography (GC).Essential oils are highly concentrated substances used for their flavor and therapeutic or odoriferous properties, in a wide selection of products such as foods, medicines and cosmetics. Extraction of essential oil is one of the most time and effort consuming process. Microwave - assisted extraction is a green technique for the extraction of natural products. (MASD) was better than (SD) in terms of rapidity, energy saving and yield. (MASD) gave higher yield than (SD) with shorter extraction time, yield of orange oil extracted by (MASD) was (1.150%) in (35min.) compared to (1.095%) in (45min.) by (SD) process, same results obtained for lemon and mandarin. It was found that the optimal microwave power was (135W) and the yield was : (1.150%, 1.115%, 0.940%) for orange, lemon and mandarin respectively, (MASD) increased extraction temperature in short time and to a higher level compared to (SD).It was found that the optimal weight was (398.56g) and the yield in (SD) was : (1.095%) and MASD (1.091%) for orange oil, same results obtained for lemon and mandarin.The best citrus peel type which gave the highest yield was orange followed by lemon then mandarin in both processes.Limonene is the most abundant component in citrus essential oil, (GC) analysis showed that the amount of limonene increased in low microwave power with long extraction time for mandarin oil it was (84.3891% at 135W in 60min.), while for (SD) it was (83.0271% in 75min.) and decreased with increasing microwave power for orange oil it was (80.9661% at 265W in 35min.) while for (SD) it was (83.2189% in 45min.), (SD) was more convenient to give high amount of limonene because of the graduate temperature rise, while in microwave extraction exposure to low microwave power for long time would give complete recovery and better quality of essential oil.

تاثير الحماية من التاكل بواسطة الليزر على سبائك الالمنيوم == The Effect of Laser Surface Melting Corrosion Protection On Al Alloys

Author name: هبة خميس اسماعيل
Supervisor name: شذى احمد سامح
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Technology - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: يهدف هذا البحث الى دراسة تاثير المعاملة بالليزر على تاكل سبائك الالومنيوم (7075, 6061, 5083) المغمورة في محلول ملحي (كلوريد الصوديوم) بمختلف التراكيز. وقد تم اعداد عينات من سبائك الالومنيوم ذات ابعاد (2 ملم) سمك وقطر (25 ملم)، وكانت تجارب الاستقطاب في مح | The objectives of the present project are to generate uniform melted layers, free of large second phases to assess the corrosion resistance of the laser treated surface in comparison with the untreated alloy. So disc samples of (7075, 6061 and 5083) aluminum alloys of 2 mm thickness and 25 mm diameter, have been prepared. Polarization tests were carried out in (M lab potentiostat / galvanostat) (Germany) at 298K temperature and (1.5, 2.5 and 3.5) % wt of NaCl solution. The experiments were carried out before and after laser surface melting by (Nd : YAG, MED - 810) pulse laser, system (Q - Switched Nd : YAG 1064/532nm). Before laser surface melting the results showed that the value of the corrosion current density obviously increases with increasing the concentration of NaCl from 1.5% to 3.5%. As well as higher Cl - ions concentration more negative pitting potential (Epit) of aluminum alloys and decrease in the electrochemical stability of aluminum. The corrosion rate for the specimen 7075 is larger than that of 6061 and 5083 aluminum alloys under the same conditions. So it means that the specimens 6061 and 5083 have high resistance to corrosion in NaCl solution After laser surface melting the results showed that the surface of aluminum alloys became more homogenous and pure after treatment.It was found that the corrosion current density decreases after Laser Surface melting at about three orders than that of untreated samples, therefore, the value of the corrosion rate of laser - treated alloy is smaller than that of the untreated. As well as the pitting corrosion potential after Laser Surface melting obviously shifted to more positive direction for all aluminum alloys in different concentrations of the NaCl solution.

تطبيق اللابفيو والخوارزمية الوراثية في السيطرة على مبادل حراري من نوع الصفائح == Application of LabVIEW And Genetic Algorithm For Controlling of Plate Heat Exchanger

Author name: ايمن فوزي زوين
Supervisor name: زيدون محسن شكور
General topic: Chemical Engineering
Specific topic: Oil Refining and Gas Technology
Degree: Master
University: University of Technology - Department Of Chemical Engineering - Chemical Engineering and Oil Refining Branch
Language: English
University location: Baghdad
First pages:
Abstract: تم دراسة السلوك الديناميكي لمبادل حراري من نوع الصفائح ( يتكون من 24 صفيحة ) والسيطرة عليه. الموديل النظري للمبادل طور بالاستناد على الموازنة الحرارية لصفائح المبادل.نتائج الموديل توضح السلوك الديناميكي للمبادل حيث تبين انه من الدرجة الاولى بالتقديم ((le | In this work the dynamic behavior of a plate heat exchanger (PHE) (consists of 24 plates) both experimentally and theoretically and the control of the system were studied. A theoretical model for the plate heat exchanger was developed based on the heat balance. A step change is carried in the hot water flow which is considered as a manipulated variable.The results of plate heat exchanger (PHE) showed that the dynamic behavior of plate heat exchanger in this work is dynamically as a first order lead and second order overdamped lag with a significant delay time as shown below : G(p)=(T ?_co (s))/(m ?_h (s) )= ((0.2645s+1.411) e^( - 5.63s))/(0.2156s^2+12.34s+1) The experimental heat transfer measurements of the plate heat exchanger (PHE) indicated that the overall heat transfer coefficient (U) is related to the water flow rate (m) by a correlation having the form : U = 10637 m0.7307 To verify the presented model, temperature control was applied theoretically and experimentally to the plate heat exchanger using conventional P, PI and PID controllers with tuning of control parameters by different methods; Ziegler - Nichols, Cohen - Coon and genetic algorithm to find the best values of proportional gain (Kc), integral time (?I) and derivative time (?D). The time domain specifications like rise time, settling time, overshoot and the performance indices, Integral Squared Error (ISE) and Integrated Time - Weighted Absolute Error (ITAE) were used to evaluate the performance of different control strategies. The PID controller gave better control results of temperature than other controllers, while Ziegler - Nichols tuning method gave better control results than Cohen - Coon. GA technique is the best method in simulation by compare with Cohen - Coon and Ziegler - Nichols methods. Therefore, GA method is suitable as best technique for systems which have shorter constant time.Cohen - Coon and Ziegler - Nichols methods were used in the experimental work to calculate the controller parameters, while GA method was not used in this stage.

تثبيط تاكل الحديد الكاربوني الواطئ في حامض الكبريتيك باستعمال كحول البولي فينيل ومستخلص نبات PIPER LONGUM == Corrosion Inhibition of Low Carbon Steel In Sulfuric Acid By PVA And Piper Longum Extracts

Author name: اياد بهاء الدين احمد
Supervisor name: ماجد ابراهيم عبد الوهاب | ابرائيل سركيس يارو
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Doctorate
University: University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: The inhibitive power of Polyvinyl Alcohol (PVA) and the synergistic effects added on the inhibition power of PVA by two types of Piper Longum (PL) Ethanol Extracts (PLEXT) were investigated toward the corrosion of carbon steel in (0.2N) H2SO4 solution in the temperature range (30 - 60?C) and PVA concentration range (150 - 2000 PPM).The corrosion rate measurements were carried out using the following two standard corrosion measurements techniques.1. Weight loss technique was applied on carbon steel plates to evaluate inhibition efficiency in presence and absence of these inhibitors.2. Electrochemical Techniques were used to validate and support inhibition efficiencies found in weight loss techniques.A detailed study of the experimental methods and results is reported for each test conducted.The weight loss results showed that PVA could serve as a corrosion inhibitor but its inhibition power was found to be low for the corrosion of carbon steel in the acidic media.It was shown that the inhibition efficiency for (PVA) decreased with increasing temperature at a given PVA concentration. On the other hand it was shown that at given temperature the inhibition efficiency of (PVA) was increased with increasing of PVA concentration until a PVA concentration of 2000 ppm PVA was reached then only a slight decrease in inhibition efficiency was observed when increasing PVA concentration further.The Maximum inhibition efficiency reached was about 71 % at 30?C & 2000 ppm (PVA) concentration, calculated by the weight loss techniques.In order to improve the inhibition efficiency of PVA, by adding 6 ml/l of ethanol extracts of piper longum (PL) to a liter of the acid solution in presence of concentrations of PVA 150,500,1000.1500, and 2000 ppm at temperatures (30,40,50, and 60?C) was investigated.Weight loss results showed a jump in inhibition efficiency (% IE) value of the modified inhibitor mixture compared with the presence of PVA alone at all (PVA) concentrations for temperature range considered in this investigation.This study demonstrated the extra inhibition power added by the (PL) fruit extracts to the organic polymer (PVA) used. Maximum inhibition efficiencies recorded were approximately 95% for Piper Longum Extract Number two (PLEXT2) at 30?C and 2000 ppm PVA.The kinetic and thermodynamic parameters regarding the adsorption process of inhibitors used was calculated.It was found that the changes corrosion rates correlates well with the Arrhenius equation in absence and presence of inhibitors.The Results showed that the adsorption of the polymer and the plant extract follows Langmuir adsorption isotherms and the adsorption of the inhibitor molecules on the metal surface is mainly physical, nevertheless the adsorption is believed to be slightly deviated from the Langmuir model at 30?C.Electrochemical analysis of the corrosion process of carbon steel in an electrochemical corrosion cell was investigated using 3 - Electrode corrosion cell coupled with a potentiostat interfaced with a computer which assisted polarization data interception and interpretation.Polarization technique was used to obtain polarization data which was recorded for carbon steel in 0.2N H2SO4 solutions in presence and absence of the inhibitors investigated. Electrochemical runs were done in the (PVA) concentrations of 150, 1000, and 2000 PPM and a temperatures of 30, 40, 50, and 60?C.Tafel slopes, Corrosion currents, and corrosion rates were calculated from polarization curves by Tafel extrapolation method. Results showed corrosion rate trends similar to findings by the weight loss method. It was indicated also that the corrosion of carbon steel in 0.2N H2SO4 is highly activity controlled.Results revealed that the inhibition action is occurring at both anodic and cathodic sites on the metal surface so that both corrosion reactions were affected, so that the composite inhibitor could be considered as mixed - type inhibitor.Electrochemical results confirmed that (PLEXT2) was more efficient as inhibition improvement additive to (PVA) than (PLEXT1) at all experimental conditions range encountered in this study.The highest inhibition efficiency recorded using Tafel polarization method was 83% obtained at 30?C and 2000 ppm of PVA with 6 ml/l PLEXT2.

تحضير الكاربون المنشط من نوى التمر باستخدام كاربونات البوتاسيوم كعامل منشط في ازالة صبغة المثيلين الزرقاء == Preparation of Activated Carbon From Date Stones By K2Co3 Activation For Methylene Blue Dye Adsorption

Author name: اسماء فاضل عباس
Supervisor name: مثنى جبار احمد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: Present study deals with the preparation of activated carbon (AC) from date stones by K2CO3 activation via microwave heating and the removal of methylene blue (MB) dye from aqueous solution by using such carbon as adsorbent. The influence of radiation time (4 - 12min), radiation power (540 - 700W) and impregnation ratio (0.5 - 2.5g/g) on the yield and MB uptake of such carbons were studied. Central composite design was used to determine the optimum preparation conditions and two quadratic models were developed to correlate the preparation variables for both responses.The optimum preparation conditions were reported as 8 min radiation time, 660 W radiation power and 1.5 g/g impregnation ratio resulting in 19.99% yield and 460.123 mg/g MB uptake. From the analysis of variance (ANOVA), it was found that the radiation time had the greatest effect on the yield while impregnation ratio had the greatest effect on MB uptake.The characteristics of AC were examined by pore structure analysis, scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR). The BET surface area and total pore volume were indentified to be 1144.25 m²/g and 0.656 m³/g, respectively. Batch adsorption study was adopted to determine the experimental adsorption isotherm data of different initial concentration of MB (50 - 450 mg/l). The equilibrium data were analyzed using Langmuir, Freundlich and Sips isotherm models. The results showed that the experimental data were well fitted with sips isotherm with maximum monolayer adsorption capacity of 484.7 mg/g. Pseudo - First order, Pseudo - Second order, and intraparticle diffusion models were used to analyze experimental kinetics data with high correlation coefficient for Pseudo - second - order model.

ازالة الكادميوم من المياه الملوثة بالترسيب الكهروكيمياوي باستخدام حزمة من الانابيب الفولاذية متحدة المركز == Removal of Cadmium From Wastewater By Electro - Deposition On Stainless Steel Concentric Tubes Bundle

Author name: انس بديوي سلمان
Supervisor name: عباس حميد سليمون | بسمة عباس عبد المجيد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Doctorate
University: University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: تم دراسة انتقال الكتلة الخاص بايونات الكادميوم الثنائية الى سطح اسطوانة دوراة مصنوعة من مادة الفولاذ المقاوم للتاكل (كقطب كاثود) بواسطة قياس التيار المحدد لتفاعل اختزال ايونات الكادميوم الكاثودي في محلول كبريتات الصوديوم بتركيز مولار باستخدام خلية ثلاثية | 1 - Mass transfer of Cd+2 ions to a smooth stainless steel rotating cylinder electrode was studied by measuring the limiting current for the cathodic reduction of Cd+2 in 0.5 M sodium sulphate supporting electrolyte by three electrodes cell with stainless steel rotating cylinder electrode working in hydrodynamic voltammetry mode. The studied parameters were electrolyte pH (4, 5, 6 and 7), initial Cd+2 concentrations (50, 100, 200, 300 and 400 ppm) and rotation rates (100, 150, 200 and 250 rpm). Cadmium ions' reduction potential for mass transfer control conditions was found to be - 0.13 V. Diffusion coefficient was determined and correlated with the bulk concentration of Cd+2 in sodium sulphate solution. The increase in pH was found to enhance the mass transfer coefficient and this effect diminishes nearly at pH=7, and the experimental data were well fitted by an empirical dimensionless correlation among the Sherwood number, Reynolds number and Schmidt number. The obtained correlation was : Sh=0.047 ?Re?^0.769 ?Sc?^0.356 For (8015.519 < Re < 20587.07) Reduction potential obtained via the voltammograms constructed by the rotating cylinder cell was applied for the two pilot scale units in order to keep the process under mass transfer control conditions. Parameters studied in these units are : initial cadmium concentration, pH, and electrolyte flow rate. The first pilot scale unit was an electrochemical reactor with smooth stainless steel concentric tubes, and the second one was an electrochemical reactor with stainless steel mesh concentric cylinders.2 - For the stainless steel smooth concentric tubes cathode, mass transfer coefficient was calculated and correlated with initial concentration.Effect of pH on mass transfer coefficient was studied and correlated, and it was found that the effect of pH was found to be completely negligible at pH=7.On the other hand, effect of flow rate on mass transfer coefficient was studied and correlated. Performance of the reactor was analyzed by introducing figures of merit for fractional conversion, specific energy consumption, space time yield and normalizes space velocity. The experimental data were correlated in a dimensionless expression as flows : Sh=0.804?Re?^0.632 ?Sc?^(1/3) For 254 < Re < 1018.3 - For the stainless steel mesh concentric cylinders was adjusted to work under mass transfer control conditions by applying the reduction potential obtained in hydrodynamic voltammetry experiments.Effect of initial cadmium concentration, pH and solution flow rate was studied and analyzed. Mass transfer coefficient was correlated with these studied parameters.Similar to smooth cathode, the mesh cathode showed a negligible response to pH at pH=7.Noticeable enhancement in mass transfer coefficient was investigated by the action of flow rate, and the mass transfer coefficient was correlated with the solution flow rate.The mesh cathode showed a higher conversion than that adopted by the smooth cathode, and showed lower cumulative current efficiency than that of smooth cathode.Mesh cathode showed specific energy consumption, space time yield and normalized space velocity higher than that for the smooth cathode.Experimental data for the mesh reactor were correlated in a dimensionless relation as follows : Sh=1.898?Re?^0.514 ?Sc?^(1/3) For 235 < Re < 943 Cadmium ions reduction reaction was found to follow a first order reaction with respect to Cd+2 concentration, and reaction rate constant was predicted under different operating conditions.

التكسير الحراري والحفازي لمخلفات البولي اثيلين البلاستيكية في مفاعل شبه دفعوي == Thermal And Catalytic Pyrolysis Of Polyethylene Plastic Waste In Semi Batch Reactor

Author name: فهمي ابو القاسم محمد
Supervisor name: عمار صالح عباس
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

استخلاص خام فوسفات عكاشات العراقية بالحوامض العضوية واللاعضوية == Leaching Of Iraqi Akashat Phosphate Ore By Organic And Nonorganic Acids

Author name: محمد يعقوب عيسى
Supervisor name: سيسيليا خوشابا هاويل | بسمة عباس عبد المجيد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Doctorate
University: University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

اختزال مركبات الكبريت من المقاطع النفطية باستخدام تقنية الاكسدة والامتزاز == Reduction Of Sulfur Compounds From Petroleum Fractions Using Oxidation Adsorption Technique

Author name: بان جابر ابراهيم
Supervisor name: NADA SADOON AHMEDZEKI
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

دراسة ريولوجية تركيبية لمحاليل كاربوكسي مثل سليلوز == Structure Rheology Of Carboxymethyl Cellulose (CMC) Solutions

Author name: مصطفى جعفر نايف
Supervisor name: طالب بهجت عمر
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Chemical Engineering
Language: English
Full text from the source: https://nahrainuniv.edu.iq/sites/default/files/Thesis_64.pdf
University location: Baghdad
First pages:

تعزيز انتقال الحرارة باستخدام مسبباب شدة الاضطراب == Enhancement Of Heat Transfer Using Turbulence Promoters

Author name: عباس نوار زناد
Supervisor name: قاسم جبار محمد سليمان
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Chemical Engineering
Language: English
Full text from the source: https://nahrainuniv.edu.iq/sites/default/files/Thesis_65.pdf
University location: Baghdad
First pages:

تفاعلات تحويل الميثان مع الاستيلين بالفعل المساعد للمناخل الجزيئية == Molecular Sieve - Catalyzed Conversion Reactions Of Methane With Acetylene

Author name: هيثم عودة مانع
Supervisor name: Shahrazad R. Raouf | Ahmed M. Barifcani
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Doctorate
University: University of Technology - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

انتاج الايثانول من الشرش باستخدام جنس خميرة الـ "Kluyveromyces"الحرة والمقيدة في مزرعة الدفعة الواحدة == Production Of Ethanol From Whey By Free And Immobilized Kluyveromyces Species In Still Batch Culture

Author name: ايناس جبار حسن
Supervisor name: Thamer J. Mohammed | Jasim Al-Hilo
General topic: Chemical Engineering
Specific topic: Biochemistry Engineering
Degree: Master
University: University of Technology - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

تنبؤ الخصائص الثرموديناميكية للنظام الثلاثي من بيانات المركب النقي == Prediction Of Thermodynamic Properties Of Ternary System From Pure Component Data

Author name: مريم خليل عودة
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

تحسين صفات البولي اثيلين عالي الكثافة لاستخدامات خاصة == Effecte Of Photo - Initiated Oxidation On Mechanical Properties Of Polyethylene Blends

Author name: نبيلة عادل محمد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Technology - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

دراسة الخواص الميكانيكية والحرارية لراتنج النوفولاك مدعم بانواع مختلفة من الالياف == A Study Of Mechanical And Thermal Properties Of Novolak Resin Reinforced With Different Types Of Fibers

Author name: صالح محمد علي سعيدان
Supervisor name: Najat J. Saleh | Abd al Ameer Al-Saidy
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Technology - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

تحسين الانتقال الحراري للغليان باضافة مواد للماء == Enhancement Of Boiling Heat Transfer By Additives To Water

Author name: محمد عبد الرحمن عبد الله محمد منصر
Supervisor name: Farqad Sami Rasheed | Abdullah A. Kandoush
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Technology - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

هيدروديناميكا الفقاعات النصف كروية == Hydrodynamics Of Spherical - Cap Bubbles

Author name: محسن عباس مشاي الحميداوي
Supervisor name: Abdullah A.Kendoush | BalasimA.Abid
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Technology - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

انتقال الحرارة بالحمل القسري من سطح كروي خلال جريان تقاطعي == Forced Convective Heat Transfer Over A Spherical Surface In Cross Flow

Author name: حسنين علي جابر الجبر
Supervisor name: عبد الله عباس كنـدوش | بلاسم احمــد عبـــد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: University of Technology - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

تنقيـة انزيـم الكوليـن استريـز البشـري مـن الـدم باستخـدام الترشيـح الهلامــي == Purification Of Human Cholinesterase Enzyme From Blood Using Gel Filtration

Author name: زينب علي عبد الجليل
Supervisor name: Majid S. Radhaa | Nahidh W. Kasser
General topic: Chemical Engineering
Specific topic: Biochemistry Engineering
Degree: Master
University: University of Technology - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

Isolation And Characterization Of A Bacteria Capable Of Degrading Some Petroleum Cuts

Author name: علي حسين الفتال
General topic: Chemical Engineering
Specific topic: Biochemistry Engineering
Degree: Master
University: University of Technology - Department Of Chemical Engineering
Language: English
University location: Baghdad
First pages:

التحقق محاكاتا ومختبريا لانتاج الديزل الحيوي عن طريسق التقطير الدفعي التفاعلي == Simulation And Experiment Investigation For Producing Biodiesel Using Batch Reactive Distillation

Author name: سارة رشيد غايب الكرخي
Supervisor name: ندى بهجت النقا ش
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Chemical Engineering
Language: English
Full text from the source: https://nahrainuniv.edu.iq/sites/default/files/Simulation%20and%20Experiment%20Investigation%20for%20Producing%20Biodiesel%20Using%20Batch%20Reactive%20Distillation.pdf
University location: Baghdad
First pages:
1 ... 20 21 22 23 24 ... 41