الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The obtained results of the present work can be summarized in the following points:
The possibility of producing zeolitic adsorbent of a micro porous nature (Zeolite-A) from a natural Egyptian source was achieved under mild reaction conditions and simple hydrothermal process. The application of the zeolitic product on contaminated water samples with different dyes; malachite green and methylene blue, was carried out.
The removal of the two mentioned dyes from contaminant water, using the synthetic zeolite-A, was proved efficient under the following optimum conditions for removal process: pH, adsorbent dose, initial dye concentration, contact time, ionic strength and temperature. Optimum conditions evaluation of kinetics, isotherm models and the thermodynamic study for the adsorption technique.
The present study also divided into four chapters: Chapter (І) Introduction, chapter (ІІ) Literature review, chapter (ІІІ) Materials and methods and chapter (ІV) Results and discussion.
Chapter (І) ”Introduction” that presented details about water pollution crisis and its effect on human health, also discussed the main contaminant we targeted (dyes) as their classification, effects and methods of removal.The chapter explains as well the main categories of zeolites as; natural, synthetic and our greater sorption featured synthesized zeolite-A (ZA) and its importance as; low cost, eco-friendly with high ion exchange capacity and high porosity adsorbent.
Chapter (II) ”Literature review” that illustrated briefly water contaminants as (organics and inorganics), both dyes malachite green (MG) and methylene blue (MB) elimination and adsorption classification as (chemisorption and physiosorption), also adsorption mechanism and fundamental awareness of the factors that influence adsorption as; (pH, adsorbent dose, dye concentration, contact time, temperature and ionic strength). The chapter explains as well previous studies data about different types of Zeolites and MG & MB dye removal.
Chapter (Ш) ”Material and methods” that partitioned into: The natural and modifying chemical materials to be used in this study for zeolite preparation and dye removal application, methods exhibited to prepare zeolite powder and the scientific procedures applied to prepare the adsorption batches for dye elimination processing, the characterization techniques, instruments utilized to identify the synthetic product and measuring of its efficiency in the pollutant adsorption and eventually, theoretical and practical adsorption batch experiments.
Chapter (Ⅳ) ”Results and discussion” This chapter is divided into two main sections. (I)-The characterization results, which may also be classified into starting material ”kaolin” and synthesized zeolite-A results. Four approaches were used to accomplish this characterization: (1) X-Ray Fluorescence testing, (2) Scanning Electron Microscopy, (3) Energy Dispersive X-ray Analysis, and (4) X-Ray Diffraction. (П)- The results of the batch adsorption technique, including malachite green and methylene blue dye results as; the effects of pH, zeolite dose, initial dye concentration, agitation time, temperature, ionic strength, kinetic and isotherm findings and these results could be summarized as;
1. Zeolitization process of metakaolinite into zeolite-A was carried out at 80 oC/ 4hours.
2. The zeolitic product was well-developed and the crystallite sizes were in the range of 1-10 micron.
3. The product was efficient with removing capacity MG and MB (98.0 and 22.7) mg/g respectively.
4. The main studied parameters and results for both dyes were:
The removal of MG and MB is improved by increasing the pH, the optimum pH value is 9.0 and 7.0. As adsorbent dose increased, the removal increased and the optimum ZA dose is 0.2g/50ml for both dyes. The removal efficiency decreases by dye concentration increase, the optimum initial dye dose is 800mg/L and 100mg/L while the maximum adsorption capacity (qmax) is 98.0 mg/g besides 22.7 mg/g respectively. The removal has been increased with ionic strength and by time, and the optimum contact time is 240 and 30 min respectively. Both dyes adsorption over ZA is best fitted with pseudo-second-order with R2=0.9853 and R2=0.9823 respectively as it also has been fitted with Langmuir isotherm model with R2= 1.0 and R2= 0.9986, which means that ZA surface is homogenous (monolayer coverage). The adsorption of MG and MB over ZA is a physical process, spontaneous and endothermic.
5. These results showed that the sorption capability of MG is higher than MB.
Finally, the produced zeolite-A showed an excellent ability in removing the two tested dyes from wastewater thus, it can be examined for the removal of other dyes at low cost and in a simple process.
CONCLUSION
This following data can precisely conclude the major outlines of this thesis:
The starting raw kaolin was subjected to a zeolitization process at mild hydrothermal lab conditions (3.0M NaOH, 80 oC, 4hours), resulted in an economic nanoporous adsorbent- zeolite-A.
The synthetic product was efficiently applied with 98mg/g and 22.7mg/g for MG & MB respectively dye removal capability, at lab optimum conditions for MG the pH 9.0, ZA dose of 0.2g/50mL, dye conc of 800 mg/L, and optimal period of 240 min. As for MB pH 7.0, ZA dose of 0.2g/50mL, dye conc. of 100 mg/L, in addition optimal period (30 min.).
The synthetic product reflected the low-silica and the high alkaline nature of the parent rock, without any negative (-ve) effect on its sorption capability for eliminating MG & MB dyes from the effluent soln.
The dye particulates linked on the adsorbent superficial via electrostatic interaction mechanism which confirmed by the reduced sorption effectiveness in existence of other cations alike (Ca+2) in MG else the existence of probable cations has a significant influence in MB uptake by dissociation of MB into MB+.
The Langmuir model was shown to be more appropriate than the other examined isotherm models, with correlation coefficients of 0.9823 as well as 0.9904, while it means that the dye is found as a homogenous monolayer over the synthesized ZA further with an elevated sorption capability that elevated with rising temp. Furthermore, according to Dubinin Radushkevich, the uptake of MG & MB found to be a physical process.
Thermodynamic considerations were determined; as spontaneous endothermic aspect sorption with a boost in the randomness of both MB & MG on the obtained zeolite-A.
The sorption kinetics found to followed second order model for both dyes. Therefore, from all previous findings in that worthy study that our synthetic zeolite-A can be considered as a promising adsorbent to eliminate cationic dyes with extraordinary sorption aptitude.
In conclusion; natural resources such as “Kaolin” was successfully utilized for preparing synthetic nano-porous adsorbent which efficiently used for MG & MB adsorption in addition, this could be applied for the removal of other types.