JournalTOCs

International Research Journal of Pure and Applied Chemistry
Number of Followers: 0

This is an Open Access Journal

Open Access journal
ISSN (Online) 2231-3443
Published by SCIENCEDOMAIN international

[65 journals]

Capillary Pressure Behavior of CO2 - Shale System at Elevated Temperatures
- Authors: Abrar Almutairi, Talal Al-Bazali
  Pages: 1 - 16
  Abstract: In this study, changes in capillary entry pressure of shale when interacting with CO2, under different temperatures have been investigated. The combined impact of temperature and petrophysical properties of shale (water content, water activity, permeability and porosity) on capillary entry pressure was addressed. Pressure breakthrough measurements were used to evaluate the minimum entry pressure of CO2 through shale. A heavy-duty oven was used to vary the temperature in order to investigate the impact of temperature on CO2 capillary entry pressure through shale. Results showed that capillary entry pressure of shale when interacting with CO2 was highly affected by temperature. Higher temperatures decreased capillary entry pressure of shale. We believe that pore dilation, where pore throat size expands due to the application of heat, may have caused this decrease in capillary entry pressure. However, in some cases higher temperature activated clay swelling that may have caused an apparent decrease in pore throat radii of shale which translated into higher capillary entry pressure. Results also showed that there exists no distinct relationship between petrophysical properties of shale and its measured capillary entry pressure when interacting with CO2 at different temperatures. Heat could alter pore throat radii and cause pore dilation which may alter measured capillary entry pressure. Interfacial tension decreases with increasing temperature and that can be attributed to the weakening of intermolecular forces at the two immiscible fluids interface. Swelling of clay could be related to temperature-induced transition from passive to an active clay.
  PubDate: 2022-05-05
  DOI: 10.9734/irjpac/2022/v23i230456
Comparative Evaluation of Industrial Phosphoric Acids Desulfation
Capabilities of Limes and Barium Carbonate
- Authors: Khouloud Kthiri, Mohamed Mehnaoui, Mustapha Hidouri, Khaled Boughzala
  Pages: 17 - 27
  Abstract: Industrial phosphoric acid is an omnipresent product in the food industry and in the production of fertilisers and detergents. The presence of impurities in the raw material results in a relatively charged acid with various chemical species at the expense of its quality and use. These impurities include sulfate ions that precipitate into phosphoric acid during its manufacture. A desulfation is thus necessary. This study focuses on the reduction of free sulfates in phosphoric acid as impurities. This resulted in the use of three different adjuvants: lime, limestone, and barium carbonate. Three initial sulfate levels mainly contained in phosphoric acid were investigated: 2%, 4% and 6%. After experimentation, the comparison between the resulting yields allows considering barium carbonate as the most effective adjuvant. The desulfation efficiency was 95% in a very short stirring time of 15 min, independently of the initial sulphate content of phosphoric acid. The tests carried out with lime and limestone also lead to very interesting desulfation rates for phosphoric acid with an initial sulfate content of 2 or 4%.
  PubDate: 2022-05-09
  DOI: 10.9734/irjpac/2022/v23i230457
Determination of Omeprazole, Esomeprazole and Pantoprazole by Quenching
the fluorescence of Eosin Y
- Authors: Ikram K. Othman, Theia’a N. Al-Sabha
  Pages: 28 - 39
  Abstract: A non-extractive, simple and sensitive spectrofluorimetric method with good selectivity has been described for the determination of the proton pump inhibitors namely; Omeprazole, Esomeprazole magnesium and Pantoprazole sodium that are used for the treatment of peptic ulcer disease. The method is based on the quenching the fluorescence intensity of the eosin Y dye, as the result of the ion-pair complex formation of the studied drugs with the dye in the presence of acetate buffer solution of pH 3.5. The quenching of the eosin Y fluorescence intensity was measured spectrofluorimetrically at 540 nm after excitation at 352 nm. At the optimum reaction conditions, the quenching values of fluorescence (∆F) and concentrations were rectilinear over the concentration ranges of 0.5–13.0, 0.7-15 and 0.3-15 µg/mL for Omeprazole, Esomeprazole magnesium and Pantoprazole sodium respectively. The recovery % values were in the range 99.92-100.56% and relative standard deviation values range was0.430-2.521 for all the studied drugs. The method was applied successfully for determination of above drugs in their pharmaceutical formulations as capsule, tablet and injectables. The method was free from interferences of common excipients.
  PubDate: 2022-05-14
  DOI: 10.9734/irjpac/2022/v23i230458