Multilayer adsorption of deuterium hydride on graphite

1998 ◽  
Vol 57 (11) ◽  
pp. 6720-6730 ◽  
Author(s):  
Hong Wu ◽  
G. B. Hess
Holzforschung ◽  
2002 ◽  
Vol 56 (1) ◽  
pp. 91-97
Author(s):  
Kei Morisato ◽  
Yutaka Ishimaru ◽  
Hiroyuki Urakami

Summary To understand the swelling phenomenon of wood in liquids,the saturated amount of adsorption of liquids onto wood and the standard free energy changes of the adsorption were determined. The saturated amount of adsorption obtained by regression for several liquids decreased with increasing molecular size of the solvents. The mechanism of wood swelling is discussed systematically taking all the liquids examined in previous experiments into account. Since methanol molecules require more energy for release from cohesive interactions within bulk liquids in the adsorption onto pre-swollen wood,the values of free energy change of adsorption for methanol were lower than the values for acetone,although the relative swelling with methanol was higher. These results suggest that although the cohesive interaction within the bulk liquids reduces adsorptivity,the phenomenon of wood swelling is influenced not only by monolayer adsorption but also by multilayer adsorption. Therefore,the cohesive interaction within the bulk liquids reduces adsorptivity but enhances the condensation which strongly influences the swelling of wood.


2015 ◽  
Vol 345 ◽  
pp. 81-89 ◽  
Author(s):  
Alexandre de O. Jorgetto ◽  
Adrielli C.P. da Silva ◽  
Marcos H.P. Wondracek ◽  
Rafael I.V. Silva ◽  
Edivaldo D. Velini ◽  
...  

2018 ◽  
Vol 7 (3) ◽  
pp. 966
Author(s):  
Kartik Kulkarni ◽  
Varsha Sudheer ◽  
C R Girish

The potential of agricultural waste cashew nut shells as an adsorbent for removing phenol from wastewater is presented in this paper. The adsorbent was treated with 3M sulphuric acid in order to improve the properties. The experimental parameters such as adsorbent dosage, concentration and temperature were optimized with response surface methodology (RSM). The isotherm data were tested with different isotherm models and it obeyed Freundlich Isotherm showing the multilayer adsorption. The kinetic data satisfied pseudo-first order kinetic model. The maximum adsorption capacity was calculated to be 35.08 mg/g proving the capability of cashew nut shells for removing phenol from wastewater.  


2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Qing Chen ◽  
Yuanyuan Tian ◽  
Peng Li ◽  
Changhui Yan ◽  
Yu Pang ◽  
...  

Shale gas is an effective gas resource all over the world. The evaluation of pore structure plays a critical role in exploring shale gas efficiently. Nitrogen adsorption experiment is one of the significant approaches to analyze pore size structure of shale. Shale is extremely heterogeneous due to component diversity and structure complexity. Therefore, adsorption isotherms for homogeneous adsorbents and empirical isotherms may not apply to shale. The shape of adsorption-desorption curve indicates that nitrogen adsorption on shale includes monolayer adsorption, multilayer adsorption, and capillary condensation. Usually, Langmuir isotherm is a monolayer adsorption model for ideal interfaces; BET (Brunauer, Emmett, Teller) adsorption isotherm is a multilayer adsorption model based on specific assumptions; Freundlich isotherm is an empirical equation widely applied in liquid phase adsorption. In this study, a new nitrogen adsorption isotherm is applied to simultaneously depict monolayer adsorption, multilayer adsorption, and capillary condensation, which provides more real and accurate representation of nitrogen adsorption on shale. In addition, parameters are discussed in relation to heat of adsorption which is relevant to the shape of the adsorption isotherm curve. The curve fitting results indicate that our new nitrogen adsorption isotherm can appropriately describe the whole process of nitrogen adsorption on shale.


2002 ◽  
Vol 20 (7) ◽  
pp. 669-681 ◽  
Author(s):  
Chih-Huang Weng

The adsorption characteristics of an anionic azo dye (New Coccine) on to sewage sludge ash were studied. Results showed that the ash could remove the dye effectively from aqueous solution. The adsorption rate was fast and could be expressed by the modified Freundlich equation. It was found that pH is the most important parameter affecting the adsorption characteristics. The experimental data were correlated well to the non-linear multilayer adsorption isotherm. The ash adsorption capacities for the dye were in the range 3.25–5.70 mol/g and were affected by the pH, ionic strength and temperature. Decreasing pH, ionic strength and temperature increased the adsorption density. The effect of electrical double-layer thickness on the adsorption was discussed. Thermodynamic parameters indicated that the adsorption was an exothermic process. Values of the first-layer adsorption energy, ΔG10, ranged from −6.86 to −7.45 kcal/mol, suggesting that the adsorption could be considered as a physical process simultaneously enhanced by the electrostatic effect. The multilayer adsorption energy, ΔG20, ranged from −4.33 to −4.51 kcal/mol, suggesting that the adsorption was of the typical physical type. On the basis of the monolayer dye adsorption capacity, the specific surface area of the ash was calculated as 3.84–6.73 m2/g.


2018 ◽  
Vol 5 (10) ◽  
pp. 2357-2367 ◽  
Author(s):  
Huan Tang ◽  
Ying Zhao ◽  
Sujie Shan ◽  
Xiaonan Yang ◽  
Dongmei Liu ◽  
...  

Two patterns for the multilayer adsorption.


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