Kinetics and Mechanistic Approach to the Oxidation of Inositol by Cerium(IV) in Aqueous Perchlorate Medium
Ismail Althagafi,
Ahmed Fawzy,
Ishaq A. Zaafarany,
Fahd A. Tirkistani,
Khalid S. Khairou
Issue:
Volume 5, Issue 5, October 2016
Pages:
87-93
Received:
7 September 2016
Accepted:
23 September 2016
Published:
11 October 2016
Abstract: Oxidation kinetics of inositol (INOS) by cerium(IV) has been studied spectrophotometrically in perchlorate medium at fixed ionic strength and temperature. The reaction showed a first order dependence with respect to [Ce(IV)] and less than unit order kinetics in both [H+] and [INOS]. Increasing both ionic strength and dielectric constant of the reaction medium increased the oxidation rate. Addition of Ce(III) product had no any significant effect on the oxidation rate. The oxidation product of inositol was identified by both spectroscopic and chemical tools as inosose. A plausible mechanistic scheme for oxidation reaction has been proposed and the rate law associated with the reaction mechanism was derived. The activation parameters of the second order rate constant were calculated and discussed.
Abstract: Oxidation kinetics of inositol (INOS) by cerium(IV) has been studied spectrophotometrically in perchlorate medium at fixed ionic strength and temperature. The reaction showed a first order dependence with respect to [Ce(IV)] and less than unit order kinetics in both [H+] and [INOS]. Increasing both ionic strength and dielectric constant of the reac...
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Evaluation of Characteristics of Activated Carbon from Rice Husk Impregnated with Zinc Chloride and Phosphoric Acid
Mohamed Ahiduzzaman,
Abul K. M. Sadrul Islam
Issue:
Volume 5, Issue 5, October 2016
Pages:
94-98
Received:
5 October 2016
Accepted:
14 October 2016
Published:
10 November 2016
Abstract: Activated carbon is essential in adsorption process of different dye and metals from waste streams. The molecular size of different species is different. So they could have some restriction to move into the pore in activated carbons smaller than their molecule size. In this regards a study is conducted to evaluate the adsorption characteristics of zinc chloride and phosphoric acid impregnated activated carbon. Methylene blue (MB) and nitrogen having two distinct molecular sizes are adsorbed to evaluate the adsorption characteristics of the activated carbons. Nitrogen molecules have access into smaller pores compared to MB molecules. Nitrogen adsorption test shows higher specific surface area compared to MB adsorption test. In methylene adsorption test, phosphoric acid impregnated activated carbon shows higher specific surface area (646 m2 g-1) compared to that of zinc chloride impregnated activated carbon (599 m2 g-1). In contrast zinc chloride shows higher specific surface area (927 m2 g-1) compared to that of phosphoric acid impregnated activated carbon (718 m2 g-1) in liquid nitrogen adsorption test. This happened because zinc chloride could develop smaller size pore in higher degree compared phosphoric acid during activation process. Results show that development of pore size is affected by two different agents. MB and nitrogen adsorption test reveals that zinc chloride activated material produced more number of small pores compared to phosphoric acid activated material. From this study it is concluded that the desired size of pores in activated carbon could be achieved for adsorption of species with specific molecular diameter by varying the type of activation agents.
Abstract: Activated carbon is essential in adsorption process of different dye and metals from waste streams. The molecular size of different species is different. So they could have some restriction to move into the pore in activated carbons smaller than their molecule size. In this regards a study is conducted to evaluate the adsorption characteristics of ...
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