تحضير وتشخيص دقائق الفا - اوكسيد الحديديك النانوية بطريقتي السول - جل والضوئية وبعض تطبيقاتها == Synthesis and Characterization of ??Fe2O3 Nanoparticles Using Sol?Gel and Photo Methods and Some Applications
Author name:
اسماء جميل علي اللامي
Supervisor name:
احلام محمد فرحان | حسين اسماعيل عبد الله
General topic:
Chemistry
Specific topic:
Physical Chemistry
Degree:
Doctorate
University:
University of Baghdad - College Of Science For Girls
Language:
English
University location:
Baghdad
First pages:
25T1709 - p.pdf
Abstract:
This study includes a search for surface that is highly applicable forremoval of some industrial dye in order to be useful in the water pollutiontreatment . Hematite ( α - Fe2O3 ) nanoparticles have been synthesized bytwo methods ( sol - gel and photo methods ) using different carboxylic acidas chelating agent at different temperatures . The morphology , particlesize and structural properties are characterized well with scanning electronmicroscopy( SEM) ,Atomic force microscopy (AFM) and X - Raydiffractometry XRD . The thermogravimetric analysis of the complexesindicate that the system is exothermic in nature .The effect ofnanoparticles on activity of liver enzyme ( GPT and GOT ) is also studiedby using different concentration of NPs . It is found that the activity ofGPT and GOT enzyme increases with decreases in nano particlesconcentrations and decreases in inhibition percentage.The greateractivation of nano was demonstrated at concentration (10 - 1 M). A numberof physical and chemical techniques has been reported for the treatment ofdye in this direction. Advanced oxidation processes ( AOPs) based on thegeneration of highly reactive hydroxyl radicals ( HO˙ ) as primaryoxidant. In the present work we investigated that oxidative degradationand decolourization of cibacron red FN - R and Victoria blue R dyes byphoto degradation were carried out to investigate the process ̕s optimaloperational conditions : pH ,nano dosage ,dye concentration andtemperatures .To obtain the best results at low cost and completetransformation of the toxic organic compounds to inorganic ions and acid.Degradation was observed - 21.38 % under dark , 77.81 % under UVlight (15W) , 82.81 % under visible light(600W ) and 58.72 % undersolar light with optimized conditions i.e pH = 3, catalyst ( α - Fe2O3 NPs= 0.046 g / l ) , concentration of cibacron red dye 3 x 10 - 5 M and oxidantIIdose H2O2 of 30 % after 180 minute . and for victoria blue ( pH=9, NPsdosage 0.031 g/l , dye conc. 3 x10 - 5 M . The results of photo degradationof dye showed that it could be used as efficient and environmental friendlytechnique for the complete degradation of organic pollutants which willincrease the chances for the reuse of waste water .The rate of photooxidation process is more affecting by the following parameters : solutionpH , initial dye concentration , NPs loading and temperature underoptimum conditions the rate of photo degradation determines are ( 11.7 x10 - 8 , 18.3 x10 - 8 mole / L - 1 . min. - 1 ) for cibacron red and victoria blue dyerespectively . The kinetic of the photo degradation of these dyes are alsostudied. And it was found that undergo the first - order pattern , the valuesof rate constant (k) calculated from first order relationship for the photo degradation of all dyes are equal to (9.7 x10 - 3 , 6.1x10 - 3 min. - 1) for C.R and V.B dye respectively . The apparent quantum yield for the photo degradation of these dyes were also determined nd found to be ( Φ = 8x10 - 3 , 6.13 x10 - 3 ) for C.R and V.B respectively . Activation energy of photo degradation process are also deduced . They were equal to ( 7.518 , 14.29 KJ / mole ) for C.R and V.B dye respectively . The present photo catalytic system is also used for the photo degradation of dyes under sun light irradiation .The rate of photo degradation is slower than that using visible light or UV light and the photolytic products are inorganic ions and acids.The photolytic products and the rate of photo degradation for these dyes were monitored by UV - Visible spectrophotometry technique,together with FTIR and GC - mass techniques. According to the kinetic studies and the identification of the photo catalytic products (final products) the photo catalytic reaction schemes were suggested for the photo - oxidative degradation for these dyes under the experimental conditions employed.
