الفهرس 
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Abstract
In recent years there have been a growing interest to find out a new
and better ways to prepare oxides of high surface area and thus high.catalytic activity.The objective of this work is the Preparation and characterization.of microporous TiO’ and V 2 O:ITi02 materials that having shape selective.properties like zeolites.This thesis consists of three chapters Chapter 1 deals with a general introduction of the subject and literatures
survey.
Chapter 2 includes the materials, preparation of the samples by
conventional and novel methods by using micelle-template Techniques,
in which different types of surfactants were utilized such as:
1-Cationic surfactants: CTAB, TB and CPB.
2- Anionic surfactants: SDS.
3- Poly -01 group’s compounds: xylitol, sorbitol and glucose.
All of these compounds are used in the preparation processes at
different conditions, pH, varying surfactant concentrations and
calcination temperatures.
Also, this chapter includes experimental procedures and techniques that
are used for samples characterization ’
Chapter 3 deals with the obtained results and discussions; this chapter
consists of six parts that are reported as follows:
Part (A): Surface properties that were determined by measuring the
adsorption of nitrogen at 77 K using conventional volumetric apparatus.
The general trend of the surface characteristics indicates the followings:-
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a) All the TiO’ and V 205ITi02 samples prepared with different methods
show high surface areas.
b) The prepared catalysts show type II, with hysteresis loop of type Fl. 4
that indicates the presence of micro-and mesoporsity, which was also
ascertained by V j-t plot. The percent of microporosity changes with the
conditions of the preparations, type of surfactants, pH and calcination
temperatures.
Part (B) Structural characterization of the catalysts and the phase
changes were determined using thermal analysis and X-ray diffraction
techniques. The results obtained from both techniques supported each
other and indicate:
a) The formation of a rutile phase at low temperature (623 K) when using
cationic surfactants and in the presence of vanadium. where the sample
prepared by using CPB in the presence of vanadium showed an anatase
phase. This indicates the role of both surfactant type and the presence of
vanadium in the formation of the phase formed.
b) The formation of anatase phase was depicted when using anionic
surfactant at different preparation conditions, except the sample prepared
at lower pH (pH=2.0). from thermal analysis data, this phase showed a
high thermal stability.
c) The formation of anatase phase was also shown with poly-ol groups at
different conditions, except the sample prepared by using glucose
showing the formation of mixed phases (rutile and anatase). This is
ascertained by thermal analysis data which indicates the presence of
peaks related to the phase transformation and rather indicates the stability
of the phase formed up to higher temperature (l073 K).
d) the absence of any peaks related to V,O; in X-ray patterns confirms.
the well dispersion of vanadium oxide in Ti02.
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e) from X-ray results, it can be seen that all the samples are in the
nanoparticle size range, and the cn.stallinity of the formed phases differs
according to varying the preparation conditions.
Part (C): Includes the results obtained by the scanning electron
microscope and showed the micrograph of the surface of the prepared
samples which indicate the variation of the surface morphology and the
particles size distribution as a result of varying the preparation conditions
Part (D): Deals with the results obtained from studying the FTIR-spectra
of the prepared samples in high wavenumbers region (3500-3800 cm -1) as
well as in low wavenumbers region (400-1000 cm ), that were
characteristic for the phase formed.
a) The results obtained supported those derived from X-ray data.
b) The shift of the bands and the variation of its intensity depend on the
preparation conditions
c) The results also confirm that there are no peaks characteristic for the
V205 phase, as revealed from X-ray results.
Part (E): Deals with the results obtained from the surface acidity
measurements of the prepared samples by adsorption of pyridine at 300 K
and traced by FTIR spectroscopy. The results obtained revealed the
presence of Bronsted and Lewis acid sites and their concentrations varied
with varying the preparation conditions.
Part (F): Includes the results obtained from the studying the
photocatalytic activity of the samples toward the reduction of Hg(II) from
the waste water. The data indicates that:
a) The samples that show higher photoactivity are the samples prepared
by using SDS at pH=7.0 (TsDs ti’O.7.())) and that prepared by glucose.
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b) The photocataMic activity was studied at different conditions for the
T s ps sample: pH of the Hg(II) solution. initial concentration of
Hg(II) solution, amount of catalyst, addition of surfactant and source of
radiation. from this data, it was found that the best conditions for having
the maximum reduction efficiency were when using 0.1 g of catalyst and
pH=5.5 of solution without surfactant and with 50 ppm as the initial
concentration.
c) It was found that the sample prepared with glucose show high
durability since the performance of the catalyst was almost same in three
runs while using fresh Hg(II) solution in each run achieving complete
photoreduction of Hg (II) in about 80 illumination time.