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تحضير وتشخيص ودراسة بايولوجية لبعض مركبات ثنائية الازو الجديدة ومعقداتها واستخدامها كوثبطات لتاكل سبيكة الفولار الكاربوني في الوسط الحامضي == Synthesis,Characterization and Biological activity Study of Some Bis - Azo Dyes and their Complexes and the use of Bis - Azo dyes as Corrosion Inhibitors for Low Carbon - Steel in acidic media
Author name:
اسراء عبد الكاظم جاسم الشمري
Supervisor name:
ساجد حسن كسار | حسام محمد كريدي
General topic:
Chemistry
Specific topic:
Chemistry
Degree:
Master
University:
University of Thi-Qar - College Of Science - Chemistry Department
Language:
Arabic
University location:
Dhi Qar
Abstract:
As it used for dyes (A1,A3) P-Phenylenediamine ,while using for dyes (A2,A4) O Phenylenediamine. | here is X for dyes (A1,A2) 3-ethoxy salicylaldehyde ,while representing for | dyes 3-methoxy salicylaldehyde. | he prepared copmpounds were identified by FT-IR spectroscopy, CHN analysis, 1H-NMR spectroscopy and GC-Mass spectroscopy.Also, determination of melting pointsWhere,XIn the recent study, four azo dyes compounds were prepared (A1-A4) and tested as The inhibition efficiency of the synthesized compounds was studied , using | weight loss method in acidic solution by corrosion rate determination for | carbon steel without and with different concentratins | ) 1 , 5 , 1 , 5 ( M | of inhibitor at different immersion times (1-5) hrs ,303K and static condition | .The inhibition efficiency of synthesized compounds was calculated ,the | optimum concentration ( 5 M ) and immersion time (5 hrs) were | determined at the same conditions.The compounds have agood corrosion | inhibition with efficiency percentage of (86.47-88.26%) for azo dyes. | The effect of temperature variation on the corrosion rate for different | concentrations (1 -5 M) of the prepared compounds was studied | by using weight loss method at four temperature degrees (303, 313,323 and | 333)K and (1-5) hrs. | The experimental results of temperature effect indicated the following : | 1-The rate of corrosion inhibitors increased with the rise of temperature, while | the corrosion rate decreased with increasing of inhibitor concentration at the | certain temperature.For example ,the corrosion rate for carbon steel in the | presence of A2 inhibitor increased from 39.22mpy at 303K to 464.75mpy at | 333K.while the corrosion rate decreased from 70.50mpy at concentration of | 1 M to 39.22 mpy at concentration of 5 M at constant | temperature of 303K. | 2-All inhibitors had high inhibition efficiency in reducing the corrosion rate.The | inhibition efficiency was decreased by increasing the temperature ,for example | inhibition efficiency for A2 inhibitor was decreased from 88.26% at 303K to | 85.44% at 333K. | 3-The adsorption of the molecules on the metal surface obey Langmuir | isotherm.The adsorption constant and free energy of adsorption were | calculated for the studied inhibitors.The results showed that the adsorption | constants were decreased with increasing the temperature and the negative | value of free energy indicated that the adsorption process is spontaneous. | 4-Thermodynamic functions H and S and the activation energy Ea were | determined.The results indicated that the activation energy for acidic solution | without inhibitor (16.21 KJmol-1 )was less than of the activation energy value | with the presence of inhibitor s, (17.08-31.07 KJmol-1 ) for azo dyes .The | positive value of enthalpy indicated that the metal dissolution process is | endothermic , while the negative value of entropy reflected the reducing in the | entropy value and formation stable layer on the metal surface. | Electrochemical method (Tafel plot) was used to evaluate the inhibition | efficiency for the azo compounds using carbon steel corrosion in 0.5M HCl | solution. The percentages of inhibition efficiency were 86.84%, 93.68%, 86.70 | and 93.06% for the inhibitors A1, A2, A3 and A4, respectively, at 303K and | concentration of 5 x 10-3M. Tafel plot results indicated that the prepared azo | dyes compounds are the doublet inhibitors type. | Studying of the growth inhibition against three types of pathogenic bacteria | namely for some pigments lecture(A1,A2) and their Nickel(II) complexes by | using diffusion method and measurement inhibition zone by using (DMSO) as a | solvent , using in this study three types from bacterial two its Gram negative | bacterial strains, Escherichia coli, Pseudomonas Aeruginosa and the other is Gram positive bacterial strains , Staphylococcus aureus , We notice that the biological activity against this bacterial showed a positivity results. | Ciprofloxacin were used as standard bactericide and compared inhibition this | bacterial with Ciprofloxacin.corrosion inhibitors in acidic medium ,0.5M HCl. These compounds have general chemical structure :
