Determination of the Adsorption Isotherms of Hydrogen on Activated Carbons above the Critical Temperature of the Adsorbate over Wide Temperature and Pressure Ranges

Langmuir ◽  
2001 ◽  
Vol 17 (6) ◽  
pp. 1950-1955 ◽  
Author(s):  
P. Bénard ◽  
R. Chahine
Keyword(s):  
Critical Temperature ◽  
Adsorption Isotherms ◽  
Activated Carbons ◽  
Temperature And Pressure

Determination of Critical Temperature of Compressed Non-Asbestos Fiber Sheet Gaskets

2004 ◽  
Author(s):  
Carlos F. A. Cipolatti ◽  
Ana M. F. de Sousa ◽  
Jose´ C. C. Veiga
Keyword(s):  
Critical Temperature ◽  
Industrial Applications ◽  
End Users ◽  
Leak Rate ◽  
Asbestos Fiber ◽  
Different Types ◽  
Fiber Sheet ◽  
Temperature And Pressure

Temperature and pressure limits of compressed non-asbestos gaskets have always been of interest to end users, as well as the gasket industry. Since flanges up to class 300 cover the majority of industrial applications of compressed fiber gaskets, a proposed procedure has been developed to clearly document the effect that temperature has on leak rate of the gasket at the maximum internal flange pressure. Different types of non-asbestos compressed gaskets were tested and results showed that for each material, there is a critical temperature after which leakage increases significantly.

Experimental Determination of the CH4 and CO2 Pure Gas Adsorption Isotherms on Different Activated Carbons

2018 ◽  
Vol 63 (8) ◽  
pp. 3027-3034 ◽  
Author(s):  
Deneb Peredo-Mancilla ◽  
Cecile Hort ◽  
Mejdi Jeguirim ◽  
Camelia Matei Ghimbeu ◽  
Lionel Limousy ◽  
...  
Keyword(s):  
Experimental Determination ◽  
Adsorption Isotherms ◽  
Gas Adsorption ◽  
Activated Carbons

Determination of the degree of adsorption and the heat of adsorption for 1-butylamine and ammonia on NaHY zeolites

1984 ◽  
Vol 49 (12) ◽  
pp. 2739-2743 ◽  
Author(s):  
Miloslav Křivánek ◽  
Pavel Jírů
Keyword(s):  
Lewis Acid ◽  
Adsorption Isotherms ◽  
Heat Of Adsorption ◽  
Brønsted And Lewis Acid

The degree and heat of adsorption of 1-butylamine and ammonia were measured on samples of NaHY zeolites activated at 400-600°C. The adsorption isotherms and calorimetric curves were compared for the two bases, and the amount of Bronsted and Lewis acid centres was determined from the calorimetric curves.

scholarly journals Computer Analysis of the Porous Structure of Activated Carbons Derived from Various Biomass Materials by Chemical Activation

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4121
Author(s):  
Mirosław Kwiatkowski ◽  
Elżbieta Broniek
Keyword(s):  
Porous Structure ◽  
Adsorption Isotherms ◽  
Computer Analysis ◽  
Activated Carbons ◽  
Chemical Activation ◽  
Adsorbed Layer ◽  
Dry Mass ◽  
Mass Ratio ◽  
Adsorption Volume ◽  
Homogeneous Surface

In this study, the preparation of activated carbons from various materials of biomass origin by activation with potassium hydroxide and a comprehensive computer analysis of their porous structure and adsorption properties based on benzene (C6H6) adsorption isotherms were carried out. In particular, the influence of the mass ratio of the activator’s dry mass to the char mass on the formation of the microporous structure of the obtained activated carbons was analysed. The summary of the analyses carried out based on benzene adsorption isotherms begged the conclusion that activated carbon with a maximum adsorption volume in the first adsorbed layer and homogeneous surface can be obtained from ebony wood at a mass ratio of the activator to the char of R = 3. The obtained results confirmed the superiority of the new numerical-clustering-based adsorption analysis (LBET) method over simple methods of porous structure analysis, such as the Brunauer–Emmett–Teller (BET) and Dubinin–Raduskevich (DR) methods. The LBET method is particularly useful in the evaluation of the influence of the methods and conditions of production of activated carbons on the formation of their porous structure. This method, together with an appropriate economic analysis, can help in the precise selection of methods and conditions for the process of obtaining activated carbons at specific manufacturing costs, and thus makes it possible to obtain materials that can successfully compete with those of other technologies used in industrial practice and everyday life.

scholarly journals Application of Bar Adsorptive Microextraction for the Determination of Levels of Tricyclic Antidepressants in Urine Samples

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3101
Author(s):  
Mariana N. Oliveira ◽  
Oriana C. Gonçalves ◽  
Samir M. Ahmad ◽  
Jaderson K. Schneider ◽  
Laiza C. Krause ◽  
...  
Keyword(s):  
Tricyclic Antidepressants ◽  
Matrix Effects ◽  
Activated Carbons ◽  
Process Efficiency ◽  
Gas Chromatography Mass Spectrometry ◽  
Selected Ion Monitoring ◽  
Experimental Conditions ◽  
Analytical Methodology ◽  
Low Efficiency

This work entailed the development, optimization, validation, and application of a novel analytical approach, using the bar adsorptive microextraction technique (BAμE), for the determination of the six most common tricyclic antidepressants (TCAs; amitriptyline, mianserin, trimipramine, imipramine, mirtazapine and dosulepin) in urine matrices. To achieve this goal, we employed, for the first time, new generation microextraction devices coated with convenient sorbent phases, polymers and novel activated carbons prepared from biomaterial waste, in combination with large-volume-injection gas chromatography-mass spectrometry operating in selected-ion monitoring mode (LVI-GC-MS(SIM)). Preliminary assays on sorbent coatings, showed that the polymeric phases present a much more effective performance, as the tested biosorbents exhibited low efficiency for application in microextraction techniques. By using BAμE coated with C18 polymer, under optimized experimental conditions, the detection limits achieved for the six TCAs ranged from 0.2 to 1.6 μg L−1 and, weighted linear regressions resulted in remarkable linearity (r2 > 0.9960) between 10.0 and 1000.0 μg L−1. The developed analytical methodology (BAμE(C18)/LVI-GC-MS(SIM)) provided suitable matrix effects (90.2–112.9%, RSD ≤ 13.9%), high recovery yields (92.3–111.5%, RSD ≤ 12.3%) and a remarkable overall process efficiency (ranging from 84.9% to 124.3%, RSD ≤ 13.9%). The developed and validated methodology was successfully applied for screening the six TCAs in real urine matrices. The proposed analytical methodology proved to be an eco-user-friendly approach to monitor trace levels of TCAs in complex urine matrices and an outstanding analytical alternative in comparison with other microextraction-based techniques.

Sign in / Sign up

Export Citation Format

Share Document