Zeolite concentrator

Cation in zeolite Concentration of the most strong pro-tic centres VoH=36I0on I [imol/g Concentration of aprotic ... 

Figure 11. V vs Ni - showing an empirical curve fit based on Ni1/3, zeolite concentration and Si/AI ratio.

This abstract definition will be explained with the actual example of gaseous permeation through a zeolite/alumina composite membrane. Here, we must investigate the effect of the five following factors on the rate of permeation the temperature (T) when the domain is between 200 and 400 °C, the trans-membrane pressure (Ap) when the domain is between 40 and 80 bar, the membrane porosity (s) ranging from 0.08 to 0.18 m /m, the zeolite concentration within the porous structure (c ) from 0.01 to 0.08 kg/kg and the molecular weight of the permeated gas (M) which is between 16 and 48 kg/kmol. With respect to the first... 

It is not difficult to observe that, by using this system of dimensionless coordinates for each factor, the upper level corresponds to -i-l, the lower level is -1 and the fundamental level of each factor is 0. Consequently, the values of the coordinates of the experimental plan centre will be zero. Indeed, the centre of the experiments and the origin of the system of coordinates have the same position. In our current example, we can consider that the membrane remains unchanged during the experiments, i.e. the membrane porosity (e) and the zeolite concentration (Cj.) are not included in the process factors. 

The purpose of this article is to review recent work concerning the characterization of the acid sites in zeolites, concentrating on the use of various techniques which can give detailed information concerning both the intensive and the extensive factors of acidity in zeolites. Due to the large number of papers being published in the area of zeolite catalysis, this review will certainly not be all-inclusive and the available literature will have greatly expanded by the time of publication. 

Metal scavengers reported to date have few cracking properties. Thus, their addition to a commercial FCC initially cause a decrease in cracking activity. However, as metals are selectively deposited on the scavenger surface, deactivation rates are significantly reduced and a cross-over point is reached at which the FCC mixture is more active (in the presence of high metals) than the parent (undiluted) FCC (Figure 15). Cross-over points depend on gas oil composition, feed metal levels, and zeolite concentration (and type) in the host FCC and on the properties of the diluents this data must be obtained experimentally. Other important concepts for residuum catalyst development have recently been reviewed by O Connor and coworkers[59]. 

Figure 2. Infrared spectra of zeolites B(P1), ZK-5, Q, and S right hand portion of figure represents a higher zeolite concentration in the wafer than in the left portion for Figures 2, 5, and 7...

Table 10. Dependence of rate of polymerization on zeolite concentration ...

Zeolite. Typical catalysts today contain 30-40% zeolite with some formulations reaching 50%. "Activity boosting" additives are currently available commercially with zeolite concentrations of 60% or more. 

Rare earth. Rare earth 38) is added to the zeolite as an activity enhancer, selectivity modifier, and to improve hydrothermal stability. Rare earth on zeolite concentrations typically vary from zero to 16 wt%. 

Figure 3.17. Kinetics of ion exchange of calcium and magnesium ions for zeolite A and zeolite X T — 25°C ion concentration = 5.36 x 10 mol/1 zeolite concentration = 1 g/1 (13)...

In the photoresist segment of the semiconductor process a very low concentration of VOC is generated. These low eoncentration VOCs can be removed by a concentration step followed by a catalytic oxidation process. The industrial application of this method is discussed below. Dilute VOC is fed to the rotating zeolite concentrator discussed in Section 22.2.2 (honeycomb rotor) where it is concentrated to 10 times of the original concentration and burned on catalysts at relatively low temperature. This saves fuel cost. The VOC is a mixture of IP A, acetone, MEK, toluene, ethyl acetate, n-hexane, propylene glycol monoethyl eflier, propylene glycol monoethyl ether acetate, andtetramethyl ammonium hydroxide. Themix-... 

Figure 22.2.3. Flow diagram of continuous air cleaning process by zeolite concentrator.

Figure 22.2.4. Continuous air cleaning unit by zeolite concentrator.

Table 1. Equilibrium uptake of methylene blue by composites having different zeolite concentration...

For diffusion in other microporous adsorbents, such as zeolites, concentration dependence is often successfully explained by this model (Ruthven, 1985)... 

---