Injection pump assembly for a combinatorial reactor and related method

An injection pump assembly 10 in a chemical delivery system for simultaneously delivering reagents into a combinatorial reactor system having multiple injectors. The assembly 10 has a plurality of injectors 12, each injector 12 being in fluid communication with one of the multiple reactors. Each injector 12 has (1) a pump 14 in which a plunger 18 sealingly moves to ingest, store and discharge a flushing solvent 20; (2) a pipette assembly 22 for loading, storing, and discharging one or more reagents into one of the reactors in the combinatorial reactor system, first and second reservoirs for retaining some of the reagents; (3) one or more hollow needles 32, each for selectively delivering a reagent 24 to the first 28 or the second 24 reservoir; (4) a first valve 34 positioned downstream of the first 28 reservoir; and (5) a second valve 36 positioned downstream of the second 30 reservoir. When each valve 34, 36 is in a closed position, the reagents 24, 48 can be stored in isolation from each other. When each valve 34, 36 is in an open position, the reagents 24, 48 may flow through the pipette assembly 22. A 3-way valve 38 is positioned between the pump 14 and the pipette assembly 22. An actuator assembly 46 is in operable communication with each of the plurality of injectors so that the 3-way valves 38 of each injector may be repositioned in unison, thereby delivering precise amounts of the flushing solvent 20 and the reagents 24, 48 in varied or consistent amounts to each reactor in the combinatorial reactor system. The inventive method involves operation of the disclosed injection pump assembly.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an injection pump assembly in a chemical delivery system for simultaneously delivering reagents into a combinatorial reactor with multiple reactors. The invention also includes a method of using the assembly.

2. Background Art

The chemical engineer and researcher practice the art and science of, for example, screening catalysts, polymerization of polyolefins, hydrogenation, carbonylation, oxidation, and hydrothermal synthesis. Typically, such processes on a commercial scale occur in reactors with large tanks. In such applications, it is desirable to discover new materials and catalysts more quickly and optimize them. It is known that replication of the environment inside large volume reactors on a smaller scale may facilitate process development.

One approach is to use the techniques of parallel chemistry. This allows the chemical engineer to run more reactions in less time, collect more accurate data, reduce costs, and increase his rate of acquisition of new knowledge.

Depending on the type of research, the requirements for parallel synthesis tools vary. For example, traditional synthetic organic chemists need tools that increase personal productivity without requiring a fundamental change in their work processes. Combinatorial chemistry specialists prefer automation. They desire to implement systems having a higher throughput, combined with reliability and increasingly sophisticated capabilities. Process chemists have another set of needs: automation to control a large number of independent reaction variables.

Argonaut Technologies of Foster City, Calif. makes available a system called Endeavor™ which is used, for example, for catalyst screening. This system brings parallel methodology to catalyst discovery and optimization. It runs eight individual pressurized, gaseous reactions simultaneously, while tracking the gas uptake in each reaction vessel. Used, for example, for polymerization, the system also is applied to such processes as hydrogenation, carbonylation, catalyst screening and other applications where control of temperature, pressure and continuous stirring are vital. Argonaut Technologies, Inc. is licensed by Symyx Technologies of Santa Clara, Calif. to manufacture and sell the Endeavor™ eight-cell-continuous-stirred parallel pressure reactor. This technology has been applied successfully in polymer research efforts, and is applicable to the discovery and optimization of a wide range of materials.

Among the prior art identified in a search that preceded this application are such U.S. Pat. Nos. as 5,716,584; 5,888,830; 6,132,686; 6,045,671; 6,306,658; and 6,326,090. Each is incorporated by reference, to the extent not inconsistent with this specification.

SUMMARY OF THE INVENTION

Against this background, there is a need for a multi-barreled injection pump that can be used with multiple injectors and actuators which pump precise, consistent amounts of any liquid—varied or constant—under pressure, into a combinatorial reactor system.

Accordingly, an injection pump assembly according to the present invention is used to form a delivery system for simultaneously delivery reagents into a combinatorial reactor system (such as the Endeavor™, as noted above) with multiple reactors.

The injection pump assembly includes a plurality of injectors. Each injector is in fluid communication with one of the multiple reactors. Each injector has a pump with a barrel in which a plunger sealingly moves to ingest, store and discharge a flushing solvent.

A pipette assembly loads, stores, and discharges one or more reagents into one of the reactors in the combinatorial reactor system. The pipette assembly has a passage, and first and second reservoirs for retaining at least some of the reagents. The passage is in fluid communication with each reservoir.

A hollow needle extends along the passage for selectively delivering a reagent to the first or the second reservoir. When another reagent is needed, a different needle is used to avoid cross contamination. A first valve is positioned downstream of the first reservoir and a second valve is positioned downstream of the second reservoir. When each valve is in a closed position, the reagents can be stored in isolation from each other. When each valve is in an open position, the reagents and the flushing solvent may flow along the passage into the combinatorial reactor system.

A 3-way valve is positioned between the pump and the pipette assembly. The 3-way valve has a first inlet port that receives the flushing solvent. A second port is connected to the pump, and a third port is connected to the passage.

An actuator assembly is in operable communication with each of the plurality of injectors. The actuator enables the 3-way valves of each injector to be repositioned in unison independently of the first and second valves, the first valves to be repositioned in unison independently of the 3-way valves and the second valves, and the second valves to be repositioned in unison independently of the 3-way valves and the first valves. In this manner, precise amounts of the flushing solvent and the reagents are delivered in varied or consistent amounts to each reactor in the combinatorial reactor system.

The method for simultaneously delivering reagents into the combinatorial reactor system includes operating the injection pump assembly discussed above.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Turning first toFIGS. 1a-1dand2a-2dof the drawings, an injection pump assembly10is depicted for use in a chemical delivery system which simultaneously delivers reagents into a combinatorial reactor system that has multiple injectors. The injection pump assembly10has a plurality of injectors12. Each injector12is in fluid communication with one of the multiple reactors (not shown). Each injector12has a pump14with a barrel16in which a plunger18sealingly moves to ingest, store and discharge a flushing solvent20.

Each injector also has a pipette assembly22for loading, storing, and discharging one or more reagents24into one of the reactors in the combinatorial reactor system. Each pipette assembly has a passage26and first and second reservoirs28,30for retaining at least some of the reagents. The passage is in fluid communication with each reservoir.

Extending along the passage26are one or more hollow needles32, each of which may selectively deliver a reagent24into the first28or second30reservoir.

A first valve34is positioned downstream of the first reservoir28. Likewise, a second valve36is positioned downstream of the second reservoir. When each valve34,36is in a closed position, the reagents24,48(FIG. 1c) can be stored in isolation from each other. When each valve is in an open position, the reagents may flow along the passage.

Positioned between the pump14and the pipette assembly22is a 3-way valve38. This valve has a first inlet port40that receives the flushing solvent20, a second port42connected to the pump, and a third port44that leads to the passage26.

In operable communication with each of the plurality of injectors12is an actuator assembly46(FIG.3). This assembly46includes 3 actuators which reposition the 3-way valves of the injectors in unison, reposition the first valves in unison and reposition the second valves in unison.

In this manner, the injection pump assembly10delivers precise amounts of the flushing solvent20and the reagents24,48in varied or consistent amounts to each reactor in the combinatorial reactor system.

The method using the subject invention is illustrated inFIGS. 1a-1dand includes the following:

(1) closing all valves except the second port42of the 3-way valve38;

(2) opening the first inlet port40of the 3-way valve38and operating the plunger18of the pump14so that the flushing solvent20at least partially fills the barrel16of the pump14;

(3) opening the second valve36and delivering a first reagent24into the first reservoir28through the needle32(FIG. 1a);

(4) withdrawing the needle32and inserting a second needle;

(5) closing the second valve36and delivering a second reagent48into the second reservoir22(FIG. 1b) through the second needle and withdrawing the second needle;

(6) closing the first inlet port40of the 3-way valve (FIG. 1c);

(7) opening the third port44of the 3-way valve38(FIG. 1c) (in practice, steps 5-7 reposition the 3-way valve from a fill to a discharge position; steps 6 and 7 are preferably performed in one operation);

(8) opening the first34and second valves36(FIG. 1d); and

(9) expelling the flushing solvent20from the pump14through the second42and third44ports, thereby discharging the flushing solvent20, the first reagent24, and the second reagent48from each injector10.

Preferably, the plurality of injectors equals eight (FIGS. 2a,2c), although it should be appreciated that in theory, any number of injectors is possible depending upon the application and spatial constraints.FIGS. 2a-2bdepict simultaneous filling of each injector assembly with the flushing solvent20.FIGS. 2c-2ddepict simultaneous discharge of the flushing solvent through the three-way valves38.FIGS. 2band2drespectively illustrate a representative of one of the injectors during the fill and discharge steps.

While two reservoirs28,30have been described with first34and second36valves, it should be appreciated that it is possible to deliver more then two reagents by using the same or additional reservoirs and valves as needed.

Preferably, as illustrated inFIGS. 2a-2d, the actuator assembly46is communicated with one or more means for energizing the assembly such as cylinders50that contain a pneumatic fluid. Preferably, the pneumatic fluid is air, although other methods including mechanical and hydraulic can be used.

FIG. 3depicts one embodiment of an actuator assembly46. The 3-way valves38are deployed in operable communication with a 180° pneumatic actuator60. A 90° pnuematic actuator62(depicted in a closed position) provides a linkage between the second valves36. Another 90° pneumatic actuator64(depicted in an open position) links the first valve34of each injector. While a mechanical linkage has been disclosed inFIG. 3, it will be appreciated that hydraulic, electronic or electrical linkage system will usefully be deployed in alternative embodiments.

Such hydraulic, electronic and electrical embodiments are intended to be included within the disclosed means for energizing the actuator assembly.