There is a common misconception that solids and flow chemistry do not mix and should be avoided at all costs. Our founders realised a long time ago that in order for flow chemistry to truly take on batch reactors then it was absolutely fundamental that the flow reactors be as versatile as possible without requiring significant alterations to existing chemistry. This meant that handling heterogenous chemistry involving solid slurries was absolutely essential due to the abundance of reactions such as hydrogenations and reductions with metal catalysts or reactions that form a precipitate for example.
The Coflore® range of flow reactors have been engineered specifically to achieve this goal and as such they are particularly capable at handling a wide-range of solid slurries accommodating a range of attributes such as whether the solids are fast-settling or slow-settling and the solid particle size.
Our in-house operator, Matthew Eccleson, has been running internal testing throughout November to allow us to provide data on the solids handling performance for a wide range of scenarios (such as varying slurry % w/v and slurry type) for our customers. A simple experiment to assess a flow system’s ability to handle slurries is to make up a suspension of calcium carbonate in water and compare the slurry % w/v that enters the system with the slurry % w/v that is recovered at the outlet of the system. Our in-house testing labs allow us to carry out full characterisation of our reactors along with complementary equipment such as Huber temperature control units so that we can better support our customers. We can also offer more bespoke feasibility testing centred around a customer’s specific chemistry- you can find out more about that here: https://www.amt.uk/flow-testing-services
In addition to our internal testing, we have recently added a publications section on our website (here) that lists a range of publications from our existing customers highlighting work that they have performed in their Coflore® systems. One paper by researchers at Apotex Pharma in Canada titled “Continuous Flow Process for Reductive Deoxygenation of ω-Chloroketone in the Synthesis of Vilazodone” highlights how the Coflore® ACR successfully handled a 23.5% w/v suspension. You can access the paper through the ACS here: https://doi.org/10.1021/acs.oprd.8b00145.
A second paper, by researchers at ECUST in China, involved a phosphorylation reaction within the ACR that precipitated triethylamine chloride. At the outlet of the ACR cell block, the solid mass fraction concentration was found to be 10.9%. No blockages were observed within the cell block even after 8 h of continuous operation. You can access the paper through the ACS here: https://doi.org/10.1021/acs.oprd.1c00105.