A Multiconfiguration Valve for Uninterrupted Sampling from Heterogeneous Slurries: An Application to Flow Chemistry

Heterogeneous chemical reactions that produce precipitates are generally considered to be poor choices for adaptation to a flowed format. Among various complexities associated with working with slurries, sampling from a moving slurry is perhaps the most challenging task as the flow-paths inside the sampling device quickly become clogged by the heterogeneous reaction matrices. We report here a new sampling strategy using a multiconfiguration sampling valve that was found to be an effective alternative to conventional sampling methods. When a model reaction that produces crystalline solid byproducts was performed using a traditional two-configuration valve, the flow-paths inside the sampling valve quickly clogged, and the process had to be shut down. Using the new multiconfiguration sampling protocol, we could maintain clear flow-paths inside the valve for extended periods of operation. With this technology in hand, we could obtain reproducible data from sampling operations and build a sampling mechanism ca...