SPE ware CEREX SYSTEM 96-II Operating Instructions Manual

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OPERATING INSTRUCTIONS

CEREX® System96-II

MULTI-CHANNEL SPE

CEREX 96-II manual rev B

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INSTALLATION

CAUTION

The SPE Processor does not include a filter on the source gas input. A clean, oil-free gas source is essential to prevent sample contamination.

Compressed nitrogen is the recommended pressure source in order to assure inert atmosphere operation. If this is not a consideration, the unit can operate using high purity filtered instrument air.

This instrument is supplied with an installation kit which includes 6 feet of 1/8” i.d. (1/4” o.d.) polyethylene tubing and connectors to 1/8” NPT or 1/4” NPT.

Using the tubing and fittings provided connect the unit to a regulated oil free gas source.

Optimum Source Pressure is 80 psig.

Min Pressure is 50 psig

Max Pressure is 100 psig

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TRAY CONFIGURATIONS

The System 96-II Pressure Processor provides the means to batch process solid phase extraction columns in the 96-position format. The System 96-II will accommodate both the integrated and the modular SPE plates stacked onto a variety of collection plates. The modular SPE plate is a CEREX® Holder plus plugin columns. Rimless CEREX® 1cc columns have been especially designed to fit into the 96-position footprint by insertion into the CEREX® Holder.

The re-usable CEREX® Holder interfaces to several collection plates which are also in the 96-position format. Depending upon the volume of the effluent, the appropriate collection tray can be selected from the ancillary products available.

The CEREX® Holder is keyed to the collection plates so that sample position is preserved throughout the SPE sequence. Both the CEREX® Holder and collection plates are keyed to match so that when they are correctly aligned, the assembly sits level on the slide tray platform.

Figure 1. Integrated CEREX collection plate assembly (right), Rimless CEREX

plate and collection plate assembly (left), Modular CEREX® SPE plate and

1cc columns (center)

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COLUMN COMPRESSION

Assemble the appropriate SPE column plate and collection plate and position the assembly on the System 96-II Pressure Processor slide tray platform. Each column will be pressurized equally even if columns are omitted. Refer to “Manifold Operation” in the following section for further explanation. Slide the slide tray to the rear of the processor until it reaches the stop locating it under

the manifold.

The two blue push buttons used to activate the compression mechanism are located on opposite sides of the front panel. Both push buttons must be pressed at the exact same time to open or close the compression mechanism. Activate the column compression mechanism by depressing the push buttons until the manifold has stopped moving (2 to 3 seconds). If you let go too soon the manifold mechanism will automatically open. This is a safety feature designed to keep your hands clear of moving parts during the compression and decompression cycle.

Decompression of the rack assembly is activated similarly. Both push buttons must be depressed simultaneously until the manifold has stopped moving. Slide the rack assembly forward until it reaches the stop and proceed with the next

step of the SPE method.

The compression speed been pre-set and is not adjustable. The pressure applied to the compression system has been pre-set and is not adjustable.

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MANIFOLD OPERATION

Each of the 96 holes in the Processor manifold are restricted in order to maintain the manifold pressure even if all of the positions are not filled by columns. With no column in place, there is approximately 0.75 +/- .05 scfh of flow through a hole at 25 psig. The principle of the restrictor manifold design is discussed in the following diagrams.

Po sitive P ressure C on trol “w ith flow restrictors”

Initial state. M a nifold pressu re b uilds to

Fig A.

controller set pressure. The effect of the restrictors is

m in im al in lim itin g flo w fr o m m an ifo ld to c o lu m n

reservoir. Reservoirs start at atmospheric pressure.

manifold block

manifold pressure chamber

gas flow “restric tor”

Input Pressure

P = 30psi

column seal

Sh o r tly af ter th e in itial s ta te, th e p re ss u re b u ild s in th e

Fig B.

column reservoir due to the fluid being held up by the flow

characteristics of the column sorbent bed. Restriction still has

m in im a l ef fe ct. E v e n tua lly th e p re ssu re b u ild s e no u g h to overcome the fluid flow resistance and the fluid begins to

pass through the sorbent bed.

Input Pressure

P = 30psi

30 psi

psi

Depending on flow characteristics of column

Fig. C.

psi

solvent or sa m p le flu id

so rb e n t b ed , p r es su r e in c o lu m n re s er v o ir sta b iliz e s.

Input Pressure

P = 30psi

30 psi

24 psi

30 psi

24 psi

30 psi

24 psi

SPE column rese rv oir

sorbent bed

Fig. D.

24 psi

W hen fluid passes through (one or more columns)

24 psi

co m ple te ly , an d th e re is m in im a l p re ss u re d ro p a cr o ss th e

column bed, the effect of the restrictor is maximized. The

restrictor becomes the primary flow inhibitor of the gas as it

pa ss e s th ro u g h th e c o lu m n to th e a tm o s p h er e.

26 psi

18 psi

Input Pressure

P = 30psi

26 psi

18 psi

psi

10 psi

empty or dry column

Inh ibiting the flo w w ith the c on stricto rs a t this tim e is help ful in tw o w a y s

minimized as compared to a system with no inhibitors. (2) the pressure rem a ins high liquid as comp ared to the empty or dry column s.

CEREX 96-II manual rev B

: (1) the amount of gas

in the columns containing

used is

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EXTRACTION FLOW ADJUSTMENT

The System 96-II Pressure Processor has a two-level gas delivery system used to pressurize the SPE columns.

One part of the system is controlled by the rotameter located on the left side of the instrument panel. By switching the “SPE FLOW RATE” selector to the left, “ADJUST FLOW” setting, the gas is delivered to the SPE Column Manifold through the adjustable flow regulator and then thru the rotameter controlled by the needle valve located at its base. The rotameter route provides a very precise and slow flow through the SPE columns by limiting the gas flow to the manifold from 0 to 2.5 SCFH.

NOTE: The rotometer needle valve is for adjustment only and is NEVER to be used as an on off valve. Use the selector valve to turn off the nitrogen flow. .

The second part of the gas delivery system provides for rapid gas flow to the manifold. This flow is controlled by adjusting the regulator located below the pressure gauge labeled “MAX FLOW.” The pressure range is 0-80 psig and is used to maximize flow through the SPE columns for processing viscous or high particulate samples or to dry the columns in situ. By switching the “SPE FLOW RATE” selector to “MAX FLOW”, gas is introduced to the manifold at the pressure set on the “MAX FLOW” regulator as indicated by the gauge located directly above it.

By turning the “SPE FLOW RATE” selector to off, no gas will flow to the manifold. It should be in the off position during the compression and decompression cycles and when not in use.

Note that the regulator is of the “locking” type. The regulator can be adjusted by pulling out on the regulator knob and turning it to the desired pressure. Once the desired pressure is set, it can be “locked in” by pushing in on the knob.

MAINTENANCE

The System 96-II Pressure Processor is a rugged unit constructed of anodized aluminum, stainless steel and plastics. However, the following items should be observed during operation:

1. Solvent spillage or overflow should be cleaned immediately in order to prevent instrument damage.

2. The column seal is silicone rubber and can be cleaned with methanol.

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COLUMN SEAL REPLACEMENT

1. Use the enclosed hex key to remove the two 1/4-20 screws fastening the manifold to the unit.

2. Lift the manifold off the standoffs and place it upside down on the table.

3. Remove old column seal from the manifold.

4. Attach the enclosed screws to the threaded holes on each corner on the bottom of the manifold.

5. Remove the backing of the replacement column seal. Use the screws for aligning and adhere the replacement column seal.

6. Once the column seal is attached remove the four screws.

7. Take the manifold and carefully set it on the standoffs. Fasten the manifold with the screws. Be sure to tighten the screws using the 3/16 hex key.

8. The column seal is silicone rubber and may be cleaned regularly with methanol.

WARRANTY

The System 96-II Pressure Processor is warranted for 90 days. Warranty repairs will be made given that the product has not been abused. It is constructed primarily of stainless steel and anodized aluminum. Other materials include silicone rubber, polyethylene and polypropylene. The controls and gauges are not solvent resistant. Some components, including the column seal, may be replaceable under the warranty. If there are any problems with the Processor parts contact CERA Inc. Customer Service at 626.814.2688 for further assistance.

Spare parts or replacements beyond the warranty period for such components as plates, manifold seals, and plumbing items are available. Contact your sales representative or SPEware Customer Service for current options and pricing.

CEREX

is a registered trademark of CERA Inc.

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HEATED MANIFOLD OPTION

Figure 2. System 96-II processor with Manifold Heater option

The Manifold Heater option provides heated gas flow through the sorbent bed and assists in removing residual moisture. The temperature is preset on the Temperature Control Unit and requires minimal heat up time. This in turn not only yields higher analyte recovery, it also allows the sorbent bed to be eluted with a more selective solvent like hexane or ethyl acetate. The result is an extract that is highly purified and free of interferences.

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