Micro-pore volume

Catalyst Micro-pore volume (cm /g) Meso-4macro-pore volume (cm /g) Total pore BET surf, volume area (cmVg) (cm /g) Pore size (A)... 

Table-. BET surface area, total pore volume, micro-pore volume, ignition temperature Tio% reduction temperature TR and average particle diameter of the Pd-ZSM-5 catalysts. ...

Samples Total micro pore volume (cm3 N2 NTP.g l) True micropore volume (cm. g-l)... 

Effect of Catalyst Properties on Regenerability Fig. 5 shows the effect of micro to macro poresurfaceareaSz/Sm on regenerability. It can be seen that there exists a strong relationship between the regenerability and Sz/Sm. It can be concluded that the increase in zeolite content (in terms of micro surface area micro pore volume) has a tendency to reduce the regeneration kinetic constant. 

Measurements of specific surfiice area and micro-pore volume... 

Nitrogen isotherms were measured by using an ASAP (Micromeritics) at 77K. Prior to each analysis, the samples were outgassed at S73K for 10 - 12 h to obtain a residual pressure of less than 10 torr. The amount on nitrogen adsorbed was used to calculate specific surface area, and the micro pore volumes determined from the BET equation [14] and t-plot method [15], respectively. Also, the Horvath-Kawazoe model [16] was applied to the experimental nitrogen isotherms for pore size distribution. 

N2 adsorption is also used to estimate the micro pore volume and the pore size distribution (see e. g. Glasauer et al. 1999) whieh ean be derived from a plot of adsorbed N2 vs. the thiekness of a statistieal monolayer, t, whieh is a function of the relative gas pressure (t-plot method). Mereury porosimetiy serves the same purpose (Celis et al. 1998). N2 adsorption isotherms have also been used to determine the fractal dimensions of Fe oxide particles (c. f.. Celis et al. 1998 Weidler et al. 1998). 

The micro pore volume (V, p.) was 32% less in the NB4MP) lfBF lPd(acac)/AC catalyst than in the AC support, At the same time the pore diameter anti the speciftc surface areas were 18% and 32% less than in the AC support material. 

Figure 15.1 Pore volume, micro pore volume, and BET surface area of various carbons from different raw materials and different modes of activation. A, wood, steam activated B, peat, steam activated C, coconut, steam activated D, wood, phosphoric acid activated.

The most important properties for the characterization of adsorbents are the porosity, the micropore and the macropoie volume, the timer specific surface, the pore size distribution, and the kind of the solid substance, compare Sect. 1. The micro-pore volume of pores below a width of 2 mu is in the range between 0.25 and 0.40 cm /g and is important for the adsorption capacity. Typical pore size distributions of oxide adsorbents show a maximum in the range of mieropores and a second maximum which is observed for macropores with diameters above 50 nm. In Fig. 9.1-1 the pore volrrme distribution is plotted a nst pore radius for the oxidic... 

Alloy Etching time [min] BET surface area [mVg] Micropore surface area [mVg] Micro- pore volume [cmVg] Total volume of pores (micro-and mesopores <100 nm) [cmVg] Average pore size [nm]... 

It can be seen from Table 6.50 that the total micro-pores volume (Vqdr) changes slightly at 1,300°C, while the Vodr changes from 0.33 to 0.036cm g at 1,900°C, and forms a kind of surface structure called as turbulent structure. Therefore, the micro-porous surface area (Sdr) is decreased from 890m to 62m g" ... 

In 1968, Sing introduced the as-analysis comparison plot methodology for specific surface area determination [2] the method found a wide application to identify the presence of porosity and evaluate (micro)pore volumes in test adsorbents. No detailed uncertainty analyses exist for pore volumes in porous materials no internationally recognized standard porous materials exist. The comparison of the amount adsorbed by standard and test adsorbents leads to a complex interplay of the combined standard uncertainty (m ) in the amount adsorbed and in the clamped cubic spline functions employed to interpolate common relative pressures and their dependent amounts adsorbed. 

NH4+ IEC moFg Al, moFg Specific surface area, mVs Micro-pore volume, mVg Meso- pore volume, mVg Ni, mol/g Ni/IEC... 

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