Spectroscopic Study of Nitric Acid and Water Adsorption on Oxide Particles:  Enhanced Nitric Acid Uptake Kinetics in the Presence of Adsorbed Water

2001 ◽  
Vol 105 (26) ◽  
pp. 6443-6457 ◽  
Author(s):  
A. L. Goodman ◽  
E. T. Bernard ◽  
V. H. Grassian
Keyword(s):  
Nitric Acid ◽  
Spectroscopic Study ◽  
Water Adsorption ◽  
Adsorbed Water ◽  
Uptake Kinetics ◽  
Acid Uptake ◽  
Oxide Particles

scholarly journals Enhanced Adsorption of Methanol by Oxidised Nutshell Carbon

2000 ◽  
Vol 18 (3) ◽  
pp. 261-266 ◽  
Author(s):  
Alan Bailey ◽  
Mike Williams ◽  
Lyndsay Dunne ◽  
Lynne Beames
Keyword(s):  
Nitric Acid ◽  
Water Adsorption ◽  
Opposite Effect ◽  
Kinetics Of Adsorption ◽  
Dry Air ◽  
Low Concentrations ◽  
Methanol Vapour ◽  
Adsorption Reduction ◽  
Enhanced Adsorption ◽  
Kinetics Of

A nutshell charcoal was oxidised and reduced and the effect of the treatments on the water adsorption isotherms and methanol vapour penetration noted. Oxidation with 6 M nitric acid increased the penetration times for methanol vapour in dry air, not by just raising the dynamic capacity at low concentrations but also by improving the kinetics of adsorption. Reduction caused the opposite effect. The improvement in the adsorption kinetics is thought to be due to surface diffusion on to the oxidised surface of the transport pores.

scholarly journals Oxidized BPL Carbons

1993 ◽  
Vol 10 (1-4) ◽  
pp. 75-84 ◽  
Author(s):  
S.S. Barton ◽  
M.J.B. Evans ◽  
J.A.F. Macdonald
Keyword(s):  
Nitric Acid ◽  
Surface Area ◽  
Water Adsorption ◽  
Adsorption Properties ◽  
Bet Surface Area ◽  
Adsorption Sites ◽  
A Value ◽  
Nitrogen Desorption ◽  
Oxidized Carbon ◽  
Increasing Temperature

A series of oxidized carbons has been prepared by treatment of the carbon with concentrated nitric acid at various temperatures, and the surface and adsorption properties of the prepared carbons studied. Water adsorption was modelled using a recently derived equation capable of predicting a value for the primary adsorption sites on the surface of a microporous carbon while fitting the experimentally determined isotherm at high relative pressures. The concentration of primary sites was seen to increase with increasing temperature of oxidation. The very highly oxidized carbon samples were found to have a significantly lower BET surface area determined from nitrogen desorption at 77 K and higher apparent density measured from mercury displacement.

scholarly journals Calorimetric and Spectroscopic Studies of Water Adsorption onto Alkaline Earth Fluorides

2005 ◽  
Vol 23 (6) ◽  
pp. 425-436
Author(s):  
Toshinori Mori ◽  
Yasushige Kuroda ◽  
Ryotaro Kumashiro ◽  
Koji Hirata ◽  
Hidehiro Toyota ◽  
...  
Keyword(s):  
Alkaline Earth ◽  
Water Adsorption ◽  
Adsorbed Water ◽  
Spectroscopic Studies ◽  
Water Molecules ◽  
Earth Fluoride ◽  
Alkaline Earth Fluoride ◽  
Pretreatment Temperature ◽  
Argon Adsorption ◽  
Ir Bands

Interactions between the surfaces of alkaline earth fluorides (CaF2, SrF2 and BaF2) and water molecules were investigated by calorimetric and spectroscopic methods. The exposed surfaces of the alkaline earth fluoride samples, with which the (100) crystalline plane is mainly associated, were found to be fully covered with strongly adsorbed water molecules, resulting in characteristic IR bands at 3684, 2561, 1947 and 1000 cm−1, respectively. This surface was homogeneous towards further water adsorption. The strongly adsorbed water molecules were almost completely desorbed from the surface on evacuating the sample up to 473 K. The heat of immersion in water also increased with increasing pretreatment temperature; this may be attributed to surface rehydration of the alkaline earth fluorides. The state of the surface changed drastically as the pretreatment temperature was increased and stabilized towards incoming water molecules. Thus, the surface formed after evacuation at temperatures greater than 473 K was resistant to hydration even after immersion in water at room temperature. This surface was relatively heterogeneous towards water adsorption, although it behaved homogeneously towards argon adsorption. These facts indicate that strongly adsorbed water molecules appear to be somewhat specific towards the adsorption of further incoming water molecules. The adsorption properties of the (100) plane of alkaline earth fluorides towards water and argon molecules depend strongly on both the electrostatic field strength and the extent of rehydration of the alkaline earth fluoride surface.

scholarly journals Evidence of nitric acid uptake in warm cirrus anvil clouds during the NASA TC4 campaign

2010 ◽  
Vol 115 ◽  
Author(s):  
Eric Scheuer ◽  
Jack E. Dibb ◽  
Cynthia Twohy ◽  
David C. Rogers ◽  
Andrew J. Heymsfield ◽  
...  
Keyword(s):  
Nitric Acid ◽  
Acid Uptake

IR and 31P NMR spectroscopic study of complexation of carbamoyl methyl phosphinates with UVI and ThIV in nitric acid solutions

2005 ◽  
Vol 54 (11) ◽  
pp. 2540-2544 ◽  
Author(s):  
T. A. Mastryukova ◽  
O. I. Artyushin ◽  
M. P. Pasechnik ◽  
E. V. Sharova ◽  
I. L. Odinets ◽  
...  
Keyword(s):  
Nitric Acid ◽  
Spectroscopic Study ◽  
31P Nmr ◽  
Acid Solutions ◽  
Nitric Acid Solutions
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