Spray chambers cyclonic

Cyclonic spray chambers greatly reduce matrix effects. 

From the sample solution to be analyzed, small droplets are formed by the nebulization of the solution using an appropriate concentric or cross-flow pneumatic nebulizer/spray chamber system. Quite different solution introduction systems have been created for the appropriate generation of an aerosol from a liquid sample and for separation of large size droplets. Such an arrangement provides an efficiency of the analyte introduction in the plasma of 1-3 % only.6 The rest (97 % to 99%) goes down in the drain.7 Beside the conventional Meinhard nebulizer, together with cooled or non-cooled Scott spray chamber or conical spray chamber, several types of micronebulizers together with cyclonic spray chambers are employed for routine measurements in ICP-MS laboratories. The solvent evaporated from each droplet forms a particle which is vaporized into atoms and molecules... 

Meinhard or MicroMist nebulizer and cyclonic spray chamber... 

Figure 5.1 Main parts of an inductively coupled plasma mass spectrometer sample introduction systems (left column), e.g., Meinhard or MicroMist nebulizer with cyclonic spray chamber, ultrasonic nebulizer, microconcentric nebulizer and laser ablation system (all from CETAC Technologies), ion source (middle column) and several types of mass spectrometers, (a) Agilent 7500 from Agilent, (b) Platform from CV Instruments, or (c) Element from Thermo Fisher Scientific. (Parts of this figure were reproduced with permission from CETAC Technologies, Agilent, CV Instruments and Thermo Tisher Scientific, respectively.)...

The APEX system (Element Scientific Inc., Omaha) as an improved Aridus nebulizer was introduced for ICP-MS in 2004 for more effective solution introduction at flow rates from 20-400 p,lmin-1.88 In this solution introduction system (see Figure 5.15), a microflow PFA nebulizer is combined with a heated cyclonic spray chamber followed by cooling of the nebulized aerosol in a condenser loop and using a multipass condenser cooled by a Peltier element. The APEX solution introduction system results in a significant increase of sensitivity (by a factor of ten in comparison to a standard nebulizer spray chamber arrangement) and a decreasing polyatomic formation rate.89... 

Figure 5.15 Experimental arrangement of microconcentric PFA nebulizer with heated cyclonic spray chamber and Peltier cooled multipass condenser APEX. (Reproduced by permission of Element Scientific Inc., Omaha).

On line additions of aqueous standard solutions for the calibration of LA-ICP-MS including a comparison of wet and dry plasma conditions are discussed by O Connor et al.ls For solution calibration of standard solutions the authors used a 100 (xl PFA nebulizer together with a cyclonic spray chamber or a MCN-6000 sample introduction system with desolvator, to study the wet and dry plasma, respectively. A polypropylene Y piece was applied to mix the laser ablated material and the nebulized standard solutions. The authors found that the on line addition of water is the preferred mode of operation for quantification by LA-ICP-MS, i.e., wet plasma is more stable (improved standard deviation of sensitivity ratios). 

Three different spray chamber designs (Fig. 3.6) are most often used for ICP-MS the Scott [15] (double-barrel) chamber, a conical chamber with an impact bead, and a cyclonic chamber [14,16,17]. The cyclonic spray chamber typically provides a slightly (up to about a factor of 2 or 3) higher analyte transport efficiency as well as somewhat shorter washout times. In some cases the spray chamber is cooled (such as on the HP 4500 ICP-MS double-pass spray chamber, which is cooled to 4°C) to reduce the amount of water vapor that enters the ICP further so that signals from polyatomic ions containing oxygen are reduced. The cooled spray chamber also helps maintain a stable spray chamber temperature. 

Figure 6 Spray chambers (a) Scott, double-pass design, (b) Conical chamber with impact bead, (c) Cyclone spray chamber (top view), (d) Cyclone spray chamber (side view).

Other elements were measured by a Perkin-Elmer SCIEX ELAN 6100 DRCII Inductively Coupled Plasma Mass Spectrometry (ICP-MS) instrument equipped with a cyclonic spray chamber, a concentric nebulizer and a dynamic reaction cell (DRC). In the vented (standard) mode, no reaction gas is present in the cell and the instrument shows the typical characteristics of a quadrupole-based ICP-MS apparatus. When the gas is introduced into the cell an ion-molecule reaction takes place that can be tailored so as to eliminate spectroscopic interferences. Experimental conditions are summarized in Table 10.2. 

To quantify the trace elements of interest plasma-based techniques were used, namely (i) ICP-AES using an Optima 3100 instrument (Perkin-Elmer, Norwalk, CT, USA) equipped with a cross-flow nebulizer and a Ryton Scott spray chamber (ii) Dynamic Reaction Cell (DRC) Q-ICP-MS using an Elan 6100 spectrometer (PerkinElmer, Norwalk, CT, USA) equipped with a quartz cross-flow Meinhard nebulizer and a cyclonic spray chamber (iii) SF-ICP-MS using an Elementl (ThermoElectron, Bremen, Germany) with a pneumatic nebulizer and a Ryton Scott spray chamber. 

Apparatus Use a suitable Inductively Coupled Plasma Emission Spectrophotometer set to 226.502 nm for cadmium and to 371.029 for yttrium (internal standard) with an axial view mode. (This method was developed using a Perkin-Elmer Model 3300 DV equipped with a sapphire injector, low-flow GemCone nebulizer, cyclonic spray chamber, and yttrium internal standard.) Use acid-rinsed plastic volumetric flasks and other labware. 

In the cyclonic spray chamber droplets are discriminated according to their size by means of a vortex produced by the tangential flow of the nebulizer. Smaller droplets are transferred with the sample aerosol into the ICP-MS, while the larger droplets collide with the walls and exit by gravity via a drain tube. If compared to the Scott design, the cyclonic spray chamber typically shows higher sensitivity. 

Spray chamber - cyclonic spray chamber for organic solvent. 

A frilly de-mountable ABC TJA IRIS Radial torch was equipped with a Twister cyclonic spray chamber for the non-hydrofluoric (HF) acid analyses. Both are available from Glass Expansion Inc, Pocasset, Massachusetts, USA. When analyzing samples prepared with a dilute HF acid solution, an alumina center tube and HF resistant spray chamber (Glass Expansion) were substituted. The nebulizer used was a Teflon Mira Mist that is available from Burgener Research Inc., Mississauga, Ontario, Canada. 

Figure 7.33 (a) The components of a liquid sample introduction system for ICP glass concentric nebulizer, demountable three piece quartz torch, torch body, and glass cyclonic spray chamber, (b) The components assembled for use. This torch design is typical of that used in Jobin Yvon ICP instruments. [Courtesy of Glass Expansion Pty, Ltd., Australia (www.GEICP.com).]... 

The following units are sized using approaches given in Section 5.2 for gas-solid separations wet cyclone, spray chamber, venturi, cross flow packed column. Steam traps ball float, open bucket, inverted bucket, liquid expansion and thermodynamic. Size on condensate flowrate. The cooler the condensate, the larger the flowrate. 

Protocol 2 is not instrument specific but, for the purpose of this discussion, will assume the use of a PerkinEImer Sciex Q-ICP-MS instrument, preferably with a PC3 or equivalent Peltier-cooled cyclonic spray chamber or dualspray chamber as the introduction system. In Protocol 2, elution of uranium from 1-mL TRU SPE cartridges is accomplished with 1% v/v (0.18 M) sulfuric add. 

Reproduced with permission of Wiley-VCH Verlag GmbH from [25]. (b) Cyclonic spray chamber. Reproduced with permission of Advanstar Communications from [27]. (c) Burgener nebulizer. Reproduced with permission ofWiley-VCH Verlag GmbH from [25]. 

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