Problems with laboratory-scale

Although gas evolution is usually endothermic in open systems, and seldom a problem on laboratory scale, industrial batch reactors combine relatively far smaller vents with lower rupture pressures. This can give dangers with even endothermic evolutions. Exothermic gas evolving reactions readily become uncontrollable. A further hazard is nucleation and heating of saturated and supersaturated gas solutions when crystallisation of products occurs this is the cause of many reactions jumping... 

By their very nature, the vapor-phase oxidation processes result in the concentration of reaction heat in the catalyst zone, from which it must bfe removed in large quantities at high-temperature levels. Removal of heat is essential to prevent destruction of apparatus, catalyst, or raw material, and maintenance of temperature at the proper level is necessary to ensure the correct rate and degree of oxidation. With laboratory-scale apparatus, removal of this heat is relatively easy in some instances, it is even necessary to provide an external supply of heat in order to maintain the operating temperature at the proper level. With plant-scale operation and with reactions involving deep-seated oxidation, removal of heat constitutes a major problem. With limited oxidation, however, it may become necessary to supply heat even to oxidations conducted on a plant scale. 

The solution of these problems is based on a simple idea the developed laboratory-scale process is used for manufacturing of a chemical product by parallelization of many small units. Although promising great advantages over scale-up, this procedure, denoted numbering-up , is not trivial by far. It cannot be carried out in a simple way due to the tremendous technological effort necessary a chemical plant with hundreds or even thousands of small-scaled vessels, stirrers, heaters, pumps. 

These issues are really major ones in research laboratories dealing with specialty chemicals and first level scale-up. Filterability can be a problem with M catalysts supported on classic materials such as carbon, owing to their tendency to pulverisation to give nanometer-sized catalyst particles that turn out to be very difficult to be recovered and successfully reused. 

The laboratory-scale fluoride transport tests revealed severe attack on the Pt plating of the electrodes. AEA is now seeking resolution of this problem with electrode manufacturers. Pt and Ti released in these attacks may plug electrode cavities or impact membrane performance. 

Industrial heterogeneous catalysts and laboratory-scale model catalysts are commonly prepared by first impregnating a support with simple transition metal complexes. Catalytically active metal nanoparticles (NPs) are subsequently prepared through a series of high temperature calcination and / or reduction steps. These methods are relatively inexpensive and can be readily applied to numerous metals and supports however, the NPs are prepared in-situ on the support via processes that are not necessarily well understood. These inherent problems with standard catalyst preparation techniques are considerable drawbacks to studying and understanding complex organic reaction mechanisms over supported catalysts. (4)... 

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