Continuous, efficient multistage extraction

Transcription

1 Continuous, efficient multistage extraction Andrea Adamo Zaiput Flow Technologies Department of Chemical Engineering, MIT Munich 01 February 2017

2 Back ground - MIT s efforts in continuous manufacturing Pharmacy on Demand - POD MIT-Novartis consortium:

3 The problem - Zaiput s solution Continuous Flow Synthesis of drugs, the future of complex chemical synthesis. (larger parameter space, more robust/repeatable processes, cost reduction) Wish Reagents Product Reality Reagents Product Currently, reaction steps are not linked, chemical work-up needed Zaiput provides the link thus enabling real continuous flow process 3

4 Inline extraction enabled by continuous separation Aqueous Non-wetting Phase Organic Wetting Phase Stretched diaphragm Water Outflow Toluene Outflow Pwater P toluene Membrane for separation High precision Pressure Control Integrated self tuning liquid-liquid separator P ( P P ) P cap water toluene per P P P cap diaphragm per P P P Inflow water diaphragm toluene 4

5 Integrated liquid-liquid separator Outflow Inflow 5

6 Summary of advantages NO need of manual adjustments, plug & play operation) Excellent chemical compatibility (wetted parts ETFE, PFA and PTFE) Operation under pressure (300 psi/20 bar max) and in line Easy to use Passive device Truly continuous No dead volume Scalable Low separation pressure differential (suitable for the majority of aqueous/organic pairs) GAS/LIQUID separation Separation of Emulsions Inherently safe 6

7 Integrated liquid-liquid separator 2 sizes already available. Forthcoming 3 liter/min version Small production/pilot plant Max flow rate 200 ml/min 1 cm Process development Max flow rate 12ml/min 27

8 Examples of applications Reaction followed by an extraction A B Reactor C- in Aqueous phase Separator Aqueous to waste Organic C in Organic Solvent Swap Organic #2 A - in Organic #1 Separator A in Aqueous Separator Aqueous to waste Aqueous Organic #1 to waste A in Organic #2 8

9 Examples of applications Analytical / process monitoring Bi-phasic stream Separator Phase 1 In line analytics Gas-liquid Liquid -liquid Phase 2 In line analytics C in Organic Typically used with small scale device Example of Analytics (IR, UV-Vis, Raman, etc ) 9

10 Examples of applications Continuous product isolation after Chromatographic purification Organic recycle Reverse phase Chromtografy ph adjustment Purified Compound in Aqueous Organic Extractant Separator Organic Evaporat or Dry pure product Waste Aqueous Waste 10

11 Example of applications Counter current extraction Aqueous + Chemical PUMP PUMP PUMP Organic Organic + Chemical PUMP Aqueous Adamo et al., Ind. Eng. Chem. Res., July

12 Current literature on Zaiput shows: Customers have written a variety of papers, types of uses are: Types of uses divided by chemistry need: Liquid-liquid extraction and simple in line work up Biphasic reaction and quenching Solvent Switch Homogeneous catalyst recovery Separation of hazardous material after in-situ production 12

13 Examples of applications Continuous-flow purification of atropine, 3 sequential extractions with in line ph adjustments (Acid base extraction) L-L Separators C. Dai et al. - J. Flow Chem

14 Example of use - Fluoxetine 1 (ketone reduction) 1. DIBALH 2. H 2 O, HCl Incompatible with 2 Al salt 2 MeNH 2 Water hinders 3 (amination) 3 (aromatic substitution) KO t BU Adamo et al. Science 2016 (Fluoxetine) 14

15 Fluoxetine - Complete process Flow Workup Flow Workup 1 Separator Al salt H 2 O Flow sequence operated at 1.7 MPa Water +HCl Separator 2 Separator 3 Water +HCl 140 C Water+NaCl+THF 140 C Multistage Extraction Possible because of device modularity 15

16 When do you use multi-stage extraction? Partition coefficient: K i = C i,organic C i,aqueous K i % extraction with 1 stage 1 50% 5 83% 10 91% % 1) Low or medium partition coefficient (K i < 10 for most ternary systems) 2) The system with molecules with similar partitions (i.e. Separation Factor SF A/B is close to 1) SF A/B = K A K B 16

17 % Extraction of p-dioxane Countercurrent cascading is the most efficient Single stage Co-current Cross-current Counter-current % left in raffinate (K i is partition coefficient) K i K i 1 N n=0 (1 + K i /N) N 1 K i n Benzene p-dioxane Water L/L extraction system Extract (p-dioxane/ benzene) Raffinate (Water) 100.0% 90.0% 80.0% 70.0% 60.0% Crosscurrent Countercurrent Cocurrent (K i ) = C i,organic C i,aqueous K i =2.4 S/F ratio = % Number of equilibrium stages [1] J.D. Seader et al, Separation Process Principles, 2 nd edition, 2006 [2] R.J. Berdt et al., J. Am. Chem. Soc., 1944, 66,

18 Process development of CC LLE presents challenges K values are now interdependent, and varied over range of concentrations Equilibrium data generally obtained by thermodynamic models (e.g. UNIQUAC, NRTL) Inaccurate due to lack of equilibrium data Unavailable physical property data especially for unidentified molecular species Experimental data is needed Batch simulation of CC-LLE is too tedious U. Injarean et al., Energy Procedia, 2014, 56,

19 Toolbox for countercurrent LL extraction Easy experimentation of CC-LLE High mass transfer Complete separation Simple scale-up At full scale, eliminate current issues Kockmann N. and Holbach A., ICNMM2013,

20 Performance studies 1 Select model system 2 Perform experiment 3 Calculate efficiency 4 Run industrial example Low Interfacial tension High Ethyl acetate-acetic acid-water K ow ~ 0.84 σ < 6 dyne/cm titration Toluene-acetone-water K ow ~ 2.90 σ = 22 dyne/cm GC A.W. Islam et al., Chem.Process Eng, 2012, 33 (2), Recovery of acetic acid by means of liquid-liquid extraction. QVF, PDF. 20

21 % overall recovery % overall recovery The problem - Zaiput s solution 1 Select model system 2 Perform experiment 3 Calculate efficiency 4 Run industrial example Ethyl acetate-acetic acid-water Toluene-acetone-water 100% 100% 80% 80% 60% 60% 40% 40% 20% 20% 0% # stages 0% # stages Experimental ASPEN simulation with 100% efficiency 21

22 Case study : THF and Ethyl Acetate recovery Challenging system with very low interfacial tension, σ = 4 dyne/cm 1 Select model system 2 Perform experiment Water 3 Calculate efficiency 4 Run industrial example THF Ethyl acetate Water Methanol Ethanol Isopropanol Tert-butanol Feed Aqueous waste (containing alcohols) Organic stream (containing THF, EtOAc) Decane Very low interfacial tension (Low P cap ) Thermodynamic models are not good enough to simulate multicomponent L-L system Variation in flow rates between stage is unknown prior to experimental runs 22

23 Multistage extraction is needed Fractions in the Organic Fractions in the Aqueous Maximize removal of alcohols from the desired organic outgoing stream Maximize recovery of THF and ethyl acetate into the organic outgoing stream Steady state within 10 min Feed Decane Water Entering at Middle stage N th stage 1 st stage Flow rate (ml/min)

24 Multistep extraction Example and scale up Biphasic Catalytic Hydrogen Peroxide Oxidation of Alcohols in Flow: Scale-up and Extraction - recovery of Phase Transfer Catalyst (PTC) Separators (SEP-10, SEP-200) Separators (SEP-10, SEP-200) Peer et al. - DOI: /acs.oprd.6b00234 Org. Process Res. Dev. August

25 Multistage extraction - Comparison Flexible capacity Simple hydrodynamics Easy scale-up Mixer-settler Centrifugal Column Zaiput High extraction efficiency Handling of emulsions Liquids with similar density Dead volume (time to steady state) Cost Suitability for many stages? Presence of solids

26 Acknowledgements Nopphon Weeranoppanant Klavs Jensen Questions? 26