Reactors automated

As noted in the introduction, a major aim of the current research is the development of "black-box" automated reactors that can produce particles with desired physicochemical properties on demand and without any user intervention. In operation, an ideal reactor would behave in the manner of Figure 12. The user would first specify the required particle properties. The reactor would then evaluate multiple reaction conditions until it eventually identified an appropriate set of reaction conditions that yield particles with the specified properties, and it would then continue to produce particles with exactly these properties until instructed to stop. There are three essential parts to any automated system—(1) physical machinery to perform the process at hand, (2) online detectors for monitoring the output of the process, and (3) decision-making software that repeatedly updates the process parameters until a product with the desired properties is obtained. The effectiveness of the automation procedure is critically dependent on the performance of these three subsystems, each of which must satisfy a number of key criteria the machinery should provide precise reproducible control of the physical process and should carry out the individual process steps as rapidly as possible to enable fast screening the online detectors should provide real-time low-noise information about the end product and the decision-making software should search for the optimal conditions in a way that is both parsimonious in terms of experimental measurements (in order to ensure a fast time-to-solution) and tolerant of noise in the experimental system. 

The microfluidic system described above has two key features that make it especially amenable to creating such automated reactors firstly, the reaction conditions can be precisely and rapidly manipulated (which in turn means that it is possible to finely tune the physical properties of the reaction product), and secondly, the inline spectrometer provides immediate real-time information about the product. The only remaining element... 

Liotta, V. Sudol, E.D. El-Aasser, M.S. Georgakis, C. On-line monitoring, modeling, and model validation of semibatch emulsion polymerization in an automated reactor control facility. J. Polym. Sci. Pt. A Polym. Chem. 1998, 36 (10), 1553-1571. 

Scheme 8.48 Total synthesis of Grossamide utilizing a fully automated reactor with supported reagents and scavengers.

Mills, P. L., Nicole, J. F., Multiple automated reactor system (MARS). 1. A novel reactor system for detailed testing of gas-phase heterogeneous oxidation catalysts, Ind. Eng. Chem. Res., 44, 2005, 6435-6452. 

The search for improved productivity in data collection has concentrated on reactor automation and the use of parallel reactors coupled to a single analytical system. This produces efficiencies and increases productivity from a given setup by a factor of five or so - too small to be revolutionary and often not very attractive in view of the cost of the automation and the added complexity of the equipment. Automated reactors also tend to be designed for a specific purpose, a feature that narrows the reactor s ability to serve in more than one investigation. 

These spectra were obtained through the oil-filled heating jacket of a laboratory scale automated reactor. Although undoubtedly a useful tool, this head is not a solution to general reaction monitoring. It copes well with the presence of bubbles and is excellent for monitoring slurries during crystallisation, but if the reaction mixture is black, as is often the case in the presence of catalyst, no reflectance is measured. 

Kauchali, S., Hausherger, B., HUdehiandt, D., Glasser, D., Biegler, L.T., 2004. Automating reactor network synthesis Finding a candidate attainahle region for the water-gas shift (WGS) reaction. Comput. Chem. Eng. 28, 149—160. 

No.lO, 30th July 1998, p.1553-71 ON-LINE MONITORING, MODELLING AND MODEL VALIDATION OF SEMIBATCH EMULSION POLYMERISATION IN AN AUTOMATED REACTOR CONTROL FACILITY Liotta V Sudol E D El-Aasser M S Georgakis C Lehigh University,Emulsion Polymers Institute... 

Fully automated reactor start-up can be achieved by the LRM, yet another passive device incorporated in the RAPID concept. Figure XVII-5 shows the LRM basic concept. LRM is similar to LIM however, Li is reserved in the active core part prior to reactor start-up. The LRM is placed in the active core region where the local coolant void worth is positive, as is also the case with LEMs and LIMs. The RAPID is equipped with an LRM bundle in which 9 LRMs and an additional B4C rod are assembled. The reactivity worth of the LRM bundle is +3.45, once each LRM includes a 95% enriched Li enclosed in a 20mm-diameter envelope. A B4C rod is used to ensure the shutdown margin (-0.5 ). An automated reactor start-up can be achieved by gradually increasing the primary coolant temperature with the primary pump circulation. The freeze seals of LRMs melt at the hot standby temperature (380°C), and Li is released from the lower level (active core level) to the upper level to achieve positive reactivity addition. An almost constant reactivity insertion rate is ensured by the LRMs because the liquid poison, driven by the gas pressure in the bottom chamber, flows through a very small orifice. It would take almost 14 hours for the liquid poison to move into the top chamber completely. A Sn-Bi-Pb alloy is used as the freeze seal material to ensure the reactor start-up at 380°C. 

Plant dynamic analyses were undertaken to demonstrate the fully automated reactor start-up. The boundary conditions were as follows start-up duration 50 000 sec (13.9 hr) reactivity insertion rate 0.0069 cents/s. 

The transient characteristics are shown in Fig. XVII-6. An automated reactor start-up was initiated from a subcritical state by the insertion of reactivity at a constant rate (0.0069 cents/s). About 2 hours after the start-up, the reactor power comes to a peak (12% overpower). Quick LEMs are actuated by this overpower to counterbalance the LRMs positive reactivity addition. Then, the net reactivity is kept slightly positive and the reactor power gradually approaches the nominal value. 

Mills PL, Nicole JF Multiple automated reactor systems (MARS). 2. Effect of microreactor configurations on homogeneous gas-phase and wall-catalyzed reactions for 1,3-butadiene oxidation, Ind Eng Chem Rjes 44 6453—6465, 2005b. 

The use of an automated reactor and solution GC-MS analysis aided rapid project delivery... 

The design and execution of DOE studies does not require robotics in order to be effective. The combination of DOE and automation can simplify the generation, collection and interpretation of large amoimts of data within a short time frame. Automated reactors may improve the reproducibility of a study, but the conclusions drawn from a well-executed study should be the same with or without their use. Automated systems can reduce much of the redundancy involved in DOE work but they are no panacea for the thought that is involved in the selection of appropriate goals, experimental parameters and evaluation tools while studying a reaction. 

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