91成人短视频

Session Chair:

• Josh Taylor, SABIC

Session Description:

Novel chemical synthesis pathways are continually being discovered that produce dilute aqueous product streams. Many of these processes involve biosynthesis (such as fermentation) or specialty chemical synthesis, but all are faced with the same process development challenge: how to recover the product in a scalable and economically feasible manner. In this session, we will present talks that focus on novel separation approaches to recovering product from dilute aqueous streams while minimizing the associated scale-up risks.

Schedule:

Abstracts:

Efficient Biocatalytic Processes Developed for Chiral and Functional Intermediates Production by Using P450 Monooxygenase and Hydratase Technologies

Iwona Kaluzna*, Martin Sch眉rmann, Thomas Schmitges, Harrie Straatman, Monika M眉ller and Daniel Mink, Royal DSM

Synthesis of chiral and functional alcohols by using enzymatic hydration (hydratases) or oxyfunctionalization (cytochrome P450) technology have attracted significant academic as well as industrial interest in the past years. Next to the availability of enzymes with sufficiently broad substrate scope and high activity, efficient reaction concepts are required for the successful application of these catalysts in biocatalytic processes. In this presentation we will highlight report on the generation of cytochrome P450 and hydratase platforms as well as exemplify the developments of successful process strategies and scale-up of both reactions types up to kg  scale.

Development of P450 platform technology enabled sustainable production of an oxygenated intermediate, on a kilogram scale. Application has resulted in unprecedented product concentration of 10 g/L and space鈥搕ime-yield of 1.5 g/L/h. In addition, exemplarily hydratase technology was implemented at ton scale and delivered the hydrated product with a space time yield of more than 7 g/L/h.

Characterizing Impeller Performance with Examples of Process Results

Richard K. Grenville, Philadelphia Mixing Solutions

Impellers in agitated vessels are often described in terms such as high flow, high efficiency, high shear etc.  These terms are qualitative and are not helpful when carrying out an agitator design / sizing calculation.   The impellers are essentially pumps, they are machines that move fluid inside the vessel, and their performance characteristics can be defined in the same way as a pump; in terms of their power input, the flow and head generated and their efficiency.

Impellers are also required to generate shear, either to disperse a second liquid, gas or solids phase in order to generate surface area for mass transfer or to promote coagulation / flocculation of fine particles suspended in the liquid phase.

The region of highest shear in a stirred tank is found in the trailing vortex at the tip of the impeller blades.  The properties of the vortex must be taken into account in order to correctly calculate a local shear rate.  In this presentation a method for quantifying the flow and shear characteristics of impellers will be presented demonstrating how this method may be applied to shear driven processes.  The calculation method will be verified by comparing with results from droplet break-up and flocculation experiments.

The main conclusion of this work is that the Rushton turbine, traditionally considered 鈥渉igh shear鈥�, actually generates larger droplets and flocs than a Hydrofoil, traditionally considered to be 鈥渓ow shear鈥� at the same power input.  Understanding this is important when selecting the appropriate impellers for processes where high or low-shear mixing are requirements.