Disk nebulizer

In the pneumatic nebulizers used in atomic spectrometry, the liquid flow is usually of the order of 1 to a few mL/min and the full efficiency of the nebulizer (a few %) can actually be realized at gas flows of 2 L/min. However, even with gas flows below 2 L/min, droplet diameters as low as about 10 pm and injection velocities below about 10 m/ s are obtained. Pneumatic nebulization can be realized with a number of types of nebulizers. For flame emission and atomic absorption as well as for plasma spectrometry, they include concentric nebulizers, so-called cross-flow nebulizers, Babington nebulizers and fritted-disk nebulizers (Fig. 40) [95]. 

Fig. 40. Pneumatic nebulizers for plasma spectrometry. A concentric glass nebulizer, B cross-flow nebulizer, C Babington nebulizer, D fritted-disk nebulizer. (Reprinted with permission from Ref. [95].)...

FIGURE 32.8 Schematic representation of the different techniques for drop formation employed in gelation (a) droplet extrusion (b) electrostatic dripping (c) laminar jet breakup (d) jet-cutting (e) jet nebulizer and (f) disk nebulizer. 

A) Concentric glass nebulizer [741 B) Cross-flow nebulizer C) Babinglon nebulizer D) Fritted-disk nebulizer... 

Fritted-disk nebulizers have high nebulization efficiencies and low sample consumption (down to 0,1-0.5 mL/min). They are especially useful for plasma spectrometry of organic solutions, or for coupling with liquid chromatography [77]. However, in comparison with other typtes of nebulizer they suffer from memory effects rinsing times are much higher than the 10-20 s required for the other pneumatic nebulizers. 

The final type of Babington nebulizer is called the Lichte or fritted disk nebulizer. The configuration of this nebulizer is shown in Figure 5.17. The nebulizer consists of a glass-enclosed, medium to coarse fritted disk, configured so that argon nebulization gas passes through the frit. Sample pumped... 

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