Reactor materials

The material of chose for the chemical reactor is crucial. In the lab, most of time we perform the reactions in glass reactors. Also during the scale up the most common choice is glass. There are several reasons for that choice: glass has excellent chemical resistance, smooth so allows easy stirring and it is also easy to clean.

For large systems, glass-lined steel units are common. The inner glass layer of a steel vessel is mecanically resistant and incorpores the advantages of the lab glass reactor (with the exception of visibility).

In spite of its advantages, it has obvious limitations. It's relativelly fragile, has low thermal conductivity, which can make it less safe than metallic reactors in large scale exothermic reactions. It is also advisable not to expose it at large temperature differentials (with the exception of borosicilated glasses). A rule may be de 50ºC rule for glass-lined steel, ie., not expose it to 50ºC variation in relativelly a short period of time so to preserve it from cracking or separation from its metal substrate.

Metal reactor vessels are often emploed. Several metallic materials are available, being the choice dependent on the use intended. 316 stainless steel is possibly the most common. Is durable, has excellent heat transfer characteristics and meets any temperature or pressure requirement.

Where acid are employed, Hastelloy is usually the choice. Is a more expensive, highly chemically resistant nickel alloy.

A very interesting general lecture on the topic of scale up, including reactor materials: www.pprbook.com