Pilot testing a reaction process, alone or as part of a multi-step process, is often a vital part of the design for the commercial scale plant. Even with available reaction kinetics there is additional information that can be gathered from testing. KMPS
has experience in the following types of reaction studies:
- Homogeneous Batch/Semi-Batch Reactions
- Homogeneous Continuous Reactions (Plug Flow)
- Reactive Distillation – Homogeneous
- Reactive Distillation – Heterogeneous
Homogeneous batch/semi-batch are the most common reaction type. They can be as simple as adding measured quantities of two or more reactants to a vessel and mixing. Heat is normally removed or added through a jacket, heating mantle or external heat exchanger.
Often they require constant removal of a product via distillation in order for the reaction to progress.
Homogeneous continuous reactions are typically plug-flow. The liquid reactants are mixed together continuously and residence time in the reactor is very short. This style is very useful for fast reactions where high throughput is essential. A reactor
for this service could be as simple as a piping loop, with or without an in-line mixer. It could also be an agitated extraction column such as SCHEIBEL®or KARR®column. Miscible or non-miscible reactants are fed to the bottom of the column, flow up through the agitated zone and exit at
the top of the column. Heating or cooling jackets are used to control the reaction temperature. In one application, a KARR®Column reactor
has replaced a series of CSTR’s and is providing higher yield and higher purity.
Homogeneous reactive distillations make use of the good mixing and heat transfer inside a distillation column. The residence time can be adjusted and the rate of reaction can be enhanced by constant removal, via distillation of the resulting products.
Typically tray columns are used for homogeneous reactive distillation. Two unit operations, reaction and distillation are performed in the same piece of equipment, which can be a considerable cost savings.
Heterogeneous reactive distillations are performed in distillation columns that have three sections. The reactor section is the middle section where a special packing Katamax® is used which contains a solid catalyst. The liquid phase reaction takes place
as the liquid film passes across the surface of the packing / catalyst. Above and below the reaction section is a rectifying and stripping section of traditional packing. Once again, two unit operations, reaction and distillation are performed in the
same piece of equipment, which can be a considerable cost savings.