In this study, removal of poisonous Pb (II) from artificially contaminated water has been investigated with the aim of detoxifying industrial effluents before their safe disposal onto land or into river waters. Five low-cost natural adsorbents, chalf, rice husk, sesame, sun flower and tea waste, were used to remove Pb from synthesized waste water. Kinetic study revealed that pseudo-first order model is suitable to explain our experimental data and intraparticle transport is not the only rate-limiting step. The adsorption equilibrium data correlate well with Freundlich model with regression, R2, range from 0.947-0.993. The results showed that efficiencies of chalf, rice husk, sesame husk, sun flower husk and tea waste for Pb ion removal were 85%, 90%, 100%, 86%, 98% repectively. High adsorption capacity of the tested adsorbents makes it preferable and very attractive alternative adsorption material. This field may therefore be utilized by developing countries to alleviate or at least, reduce the impacts of industrial water pollution on the aquatic environment.

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The suggested work included simple accurate diazo-coupling spectrophotometric method for the determination of phenylephrine-HCl (PHEPH) in pure drug and tablet formulation. The method was based on coupling of PHEPH with diazotized 2,4-dinitroaniline in alkaline medium. The sensitivity expressed by the value of molar absorptivity of yellowish-orange azo-dye was 1.915 ×10 4 L. mol-1. cm-1 , the maximum absorption at 455 nm and Beer's law obeyed within the range of 10-200 μg/10ml of PHEPH. The color of the product was highly stable and did not show a significant change in absorbance up to 60 min. with a recovery of 99.97% and a RSD% is 0.024%. The PHEPH in nose drop and syrup has been estimated with satisfactory results.

A simple and sensitive indirect spectrophotometric method was developed for the determination of folic acid in pure form and in its pharmaceutical formulations. The method was based on the oxidation of folic acid by iron (III) in acidic medium, then reaction of liberated iron (II) with 2, 2'-bipyridyl to produce a red complex which is water-soluble, stable, and has a maximum absorption at 520 nm against the reagent blank with a molar absorptivity of 2.8338 x 105 L .mol-1.cm-1. Beer’s law is valid over the concentration range of 0.5-18.0 µg/ml folic acid. The values of some thermodynamic parameters [free energy change (∆G), enthalpy change (∆H), and entropy change (∆S)] were estimated from the values of stability constants (K) at different temperatures .It was found  that  colored product formation was spontaneous, exothermic and accompanied by an increase of random. The proposed method has been applied successfully to determine folic acid in different pharmaceutical preparations.

Zeolites are compounds which have many applications in chemistry and industry; therefore, studies of synthesis of zeolites are of great importance. In this work, kinetic and thermodynamic study of hydrothermal crystallization for zeolite synthesis process performed at different time intervals (17, 20, 23 and 26 h) and various temperatures (70, 90, 110 and 125 0 C). By time intervals we got out the rate of the zeolite synthesis reaction in this research was first order. The synthesized zeolites were similar in their crystallinity according to the Zeolites synthesis at different of the time intervals. The thermodynamic parameters indicated that the change in Gibbs free energy was negative value. The degrees of crystallinity of the synthesized zeolites decreased with increasing the hydrothermal crystallization temperature. Moreover, the change of hydrothermal crystallization time and temperature caused synthesis of different types of zeolites. The synthesized zeolite samples characterized by Infra-Red (IR), X-ray diffraction (XRD), X-ray Fluorescence (XRF) and scanning electron microscopy (SEM). The variation of chemical compositions led to differences in morphologies and crystallinity of the synthesized zeolites.