Wikisheet Reactive Extraction

Transcription

1 Wikisheet Reactive Extraction Reactive Extraction Conventional L/L extraction + reaction Objective Contribute to energy efficiency program Background, Wikisheets Process Intensification within the PIN-NL program 2016 project Parties Focal points Phone Author Vincent Kroeze Co-author Henk van den Berg T h.vandenberg@utwente.nl M Second reading and comments Henk Akse, chairman PIN-NL T M henk.akse@traxxys.com Version, date 9 February 2017 Document: WikiRECv4 Status Version 4 Comments: Wiki Reactive Extraction Column version 4 9/2/17 1

2 1. Description In the Reactive Extraction process (RE), an extraction and reaction are combined in a single vessel, which reduces the number of required process steps. Figure 1: Schematic representations of the Reactive Extraction (RE) process, extraction and back extraction. C = carbocylic acid, S = Reactive Solvent. Retrieved from (Datta et al. 2015). The combination of extraction and reaction also increases the distribution coefficient and the separation efficiency, and intensifies solvent extraction compared to conventional Liquid-Liquid Extraction (LLX), see also Figure 2 below (Cascaval & Galaction 2004). The equipment required for RE is the same as with LLX: Mixer-settlers, centrifuges, nondispersive membranes and columns; the column types can be agitated or non-agitated (Bart 2007). Two types of RE systems are distinguished: solid-liquid and liquid-liquid, where the reaction can take place in one of the phases or at the phase boundary and can be catalyzed by either a homogeneous or heterogeneous catalyst (Lee & Lim 2013). RE also distinguishes 4 methods of operation (Lutze & Górak 2016): - Move/overcome mass transfer limitations: increasing the capacity of the solvent by reaction with the solute. - Setting mass transfer limitations: for example keeping a homogeneous catalyst in place by distributing the product and catalyst in separate phases. - Move/overcome reaction limitations: equilibrium limited reactions can be moved to the product side by selective extraction of products. - Set reaction limitations: If one reactant is poisonous for the catalyst or enzyme or when high concentrations can lead to unwanted by-products, e.g. dimers, it can be added in a second phase. RE is especially useful when the solute can be converted to another value added product, however regeneration of the reactive solvent allows for the recovery of the original extracted substance and recycle of the extractant (Datta et al. 2015). Figure 2 also shows the clear advantage of RE in diluted systems. Wiki Reactive Extraction Column version 4 9/2/17 2

3 Figure 2: Variation of the physical and reactive extraction degree with initial concentrations of monocarboxylic acids. Retrieved from (Cascaval & Galaction 2004) 2. Process envelope Currently RE has been applied in specific operations and occupies a niche within industrial separations/reactions. It has shown potential in extractions from diluted systems, reducing the energy cost by preventing the need for distillation or by intensification of the solvent extraction. Other benefits of RE are: smaller waste streams, higher degree extraction of value added products and smaller equipment size (Bart 2005; Talnikar & Mahajan 2014; Kiss & Bildea 2012; Datta et al. 2015). The use of RE also imposes some constraints on the design and operation of the column, as only a limited amount of extractions/reactions can be considered for this technology, see also the figure below (Wasewar 2012). Figure 3: Design window for Reactive Extraction, based on figure from (Wasewar 2012) Wiki Reactive Extraction Column version 4 9/2/17 3

4 As effective design rules are as of yet unknown, the implementation of RE still requires extensive design effort and bench- and pilot plant scale-up steps before a full scale system can be acquired (Bart 2005; Bart et al. 2008, Talnikar 2014). The conditions for the extractant can be summarized by (Datta et al. 2015): - Reacts with the solute - High distribution and selectivity towards the solute - Immiscible in second phase - Product is value added or the reaction is reversible - If second phase is aqueous: Non-aromatic - If pure extractant is corrosive, a diluent is required 3. Advantages summarized - In the Reactive Extraction process (RE), an extraction and reaction are combined in a single vessel, which reduces the number of required process steps. - The combination of extraction and reaction also increases the distribution coefficient and the separation efficiency, and intensifies solvent extraction compared to conventional Liquid- Liquid Extraction (LLX) - RE has shown potential in extractions from diluted systems, reducing the energy cost by preventing the need for distillation or by intensification of the solvent extraction. 4. Commercial status / TRL level Applications of RE are primarily found in the hydrometallurgy sector, but often use a more simple mixer-settler set-up. Chelation of the dissolved metals in aqueous phase and extraction to an organic phase is the applied method, for example Co/Ni can be separated by use of CYANEX by Cytec. Other examples include (Chadwick 2011): - Ni/Co/Cu, Vale-Inco, Voisey Bay (2011) - U, UraniumOne, Honeymoon (2008) and Dominion reefs (2007) - U, BHPB, Olympic Dam (2003) - Ni/Co/Zn, Preston, Bulong Nickel (1999) All of the mentioned examples make use of the Bateman Settler and/or Bateman Pulsed Column (BPC) technology. The amount of mining operations using extractive methods is increasing as the technology for metal leaching/extraction is reaching maturation and requires less energy compared to conventional methods. The TRL for mining applications is 9. Several publications report studies on separations for bio related systems, e.g. carboxylic acids from broths. The TRL for these systems is set at 7. Wiki Reactive Extraction Column version 4 9/2/17 4

5 5. Examples of application Some niche applications, with TRL 9, applying RE are (Lutze & Górak 2016): - SHOP (Shell Higher Olefins Process): produces linear alpha olefins from ethylene and a non-polar phase selectively removes the higher olefins. - Merox process: Mercaptan Oxidation from liquid fuels using a cobalt catalyst in basic aqueous solution, disulfides are removed in a gas phase. - PUREX process: recovery of Plutonium and Uranium from nuclear waste, these are chelated and extracted in an organic phase, the waste remains in the aqueous phase. Other applications of RE are still in the research phase, but the main focus is in the following topics: - Pharmaceutical o Antibiotics (Cascaval & Galaction 2004) o Amino acids (Cascaval & Galaction 2004) o Intermediates (Datta et al. 2015) o Vitamins (Datta et al. 2015) - Carboxylic acids from fermentation broths (Cascaval & Galaction 2004; Datta et al. 2015) - Inorganic acids recovery (Datta et al. 2015) - (Heavy) Metal recovery o From waste streams (Datta et al. 2015) o In mining operations (Datta et al. 2015; Chadwick 2011) o Environmental remediation (Datta et al. 2015) - Biodiesel production (FAME) (Kiss & Bildea 2012; Lee & Lim 2013) Relevant issues: recovery of high value products and/or avoiding pollution. TRL for above mentioned topics is 4 or more. 6. Technology and developments LLX and RE share the same type of technology and equipment, though RE will require stronger process control and has reduced flexibility compared to LLX. This is due to the required overlap of reaction and separation conditions, the resulting condition is a compromise of both. Design of a RE is difficult and limited by lack of accurate equilibrium models describing possible systems, kinetic models describing extraction with chemical reaction (Datta et al. 2015) and the requirement of computational power in CFD simulations (Bart et al. 2008). (Bart et al. 2008) describes that for the design of a REC the following is required: - Reactive equilibrium of the multicomponent feed - Microkinetics defining the chemical reactions - Macrokinetics defining diffusion and reaction - Parameters for hydrodynamic modeling of the column Currently there is some focus in developing models describing RE, by using coupled hydrodynamic, mass transfer and bivariate droplet population balance models (BDPBM) for the simulations of counter-current liquid liquid extraction columns, using experimental data from single droplet experiments (Bart et al. 2008). Wiki Reactive Extraction Column version 4 9/2/17 5

6 The technology for retrieving metal ions from aqueous solutions is reaching maturity and is finding new application in the recovery of metal ions from waste streams, such as Zn, Cd, Pt, Pd, etc. (Bart 2003, and more recent examples given above). New applications of RE are in the recovery of carboxylic acids from fermentation broths/waste streams (acetic, lactic, propionic, succinic, ), producing value added products or recovery of the pure acid via re-extraction (Joglekar et al. 2006; Kurzrock & Weuster-Botz 2010; Datta et al. 2015). Datta et. al give an overview of carboxylic recovery studies and findings. Another novel application of RE, currently under investigation, is the production of biodiesel/fame from biomass (Kiss & Bildea 2012; Lee & Lim 2013). Using either a sol-liq interface using pure biomass ((Lee & Lim 2013) Jatropha seeds) or a liquid-liquid interface and using an acid/base catalyst with methyl-/ethylacetate for the transesterification (Kiss & Bildea 2012; Kiss 2014). No known (demo) plants exist yet. RE has also been mentioned in more complex systems combining reactive separation methods in a single vessel, e.g. combination of RE with RD to recover 1,3-propanediol (Adams & Pascall 2012). Observations of the authors of this Wikisheet: RE research is more directed at novel sources for chemical building blocks, e.g. fermentation broths or biomass, than intensification of current processes. No recent sources were found mentioning energy/equipment savings by applying RE as process intensification in lieu of conventional processes. 7. Potential for industrial branches - Waste water treatment (MJA3) - Chemical process industries (MJA3 + MEE) - (hydro)metallurgic industry (MJA3 + MEE) - Oil and gas producing industry (MJA3) - Refineries (MEE) - Environmental Technology (MJA3) - Pharmaceutical industry (MJA3) - Bio based industries (MJA3) 8. Self assessment for application - First determine applicability of LLX by considering the following (de Haan & Bosch 2013): o Stream containing dissolved or complexed inorganic product in organic or aqueous solution o Removal or recovery of components present in small concentrations o Stream containing a high boiling product in relatively low concentrations o Recovery of heat sensitive product, requiring moderate process conditions o Separation of product according to chemical type rather than relative volatility Wiki Reactive Extraction Column version 4 9/2/17 6

7 o Separating mixtures that form azeotropes or exhibit low volatilities - Determine distribution/selectivity and separation efficiency in conventional LLX and optimal solvent. - For low distribution/selectivity/separation efficiency, RE has potential: o Identify a suitable solvent/reactant o Determine operational mode (e.g. batch, semi-batch, continuous) o Determine the connection (single/multi stage, crossflow or co-/countercurrent o Select equipment (Lutze & Górak 2016) - For LLX (or other separation) followed by esterification or etherification, RE has potential - For metal recovery, contact (hydro) metallurgy supplier - Other applications, initiate R&D process 9. Tags Process intensification, in the Reactive Extraction process (RE), an extraction and a reaction are combined in a single vessel, creating new and more efficient separation opportunities. 10. References Adams, T.A. & Pascall, A., Semicontinuous Thermal Separation Systems. Chemical Engineering and Technology, 35(7), pp Available at: [Accessed December 5, 2016]. Bart, H.-J., Reactive Extraction Columns High Throughput & High Selectivity, European Roadmap of Process Intensification, Technology report Bart, H.-J., Drumm, C. & Attarakih, M.M., Review: Process intensification with reactive extraction columns. Chemical Engineering & Processing: Process Intensification, 47, pp Available at: &db=edselp&an=s &lang=pl&site=eds-live. Bart, H.J., Reactive Extraction: Principles and Apparatus Concepts. In Integrated Chemical Processes: Synthesis, Operation, Analysis, and Control. pp Bart, H.J., Reactive extraction in stirred columns - A review. Chemical Engineering and Technology, 26(7), pp Cascaval, D. & Galaction, A.-I., New extraction techniques on bioseparations: 1. Reactive extraction. Hemijska industrija, 58(9), pp Available at: and Profesional Documents/Profesional Engineering Documents/Papers/Penicillin Papers/01- cascaval.pdf. Chadwick, J., SX/EW growth. International Mining, pp Available at: Datta, D. et al., Status of the Reactive Extraction as a Method of Separation. Journal of Chemistry, 2015, pp Available at: [Accessed December 5, 2016]. de Haan, A. & Bosch, H., Industrial Separation Processes, Fundamentals, Berlin, Boston: Wiki Reactive Extraction Column version 4 9/2/17 7

8 De Gruyter. Available at: file:// Joglekar, H.G. et al., Comparative assessment of downstream processing options for lactic acid. Separation and Purification Technology, 52(1), pp Kiss, A.A., Process Intensification Technologies for Biodiesel Production. Reactive Separation Processes, Kiss, A.A. & Bildea, C.S., A review of biodiesel production by integrated reactive separation technologies. Journal of Chemical Technology and Biotechnology, 87(7), pp Kurzrock, T. & Weuster-Botz, D., Recovery of succinic acid from fermentation broth. Biotechnology Letters, 32(3), pp Lee, K.T. & Lim, S., Reactive Extraction Technology. In Process Intensification for Green Chemistry: Engineering Solutions for Sustainable Chemical Processing. pp Lutze, P. & Górak, A. eds., Reactive and Membrane-Assisted Separations, Berlin, Boston: De Gruyter. Available at: ml [Accessed December 5, 2016]. Talnikar, V.D. & Mahajan, Y.S., Recovery of acids from dilute streams : A review of process technologies. Korean Journal of Chemical Engineering, 31(10), pp Wasewar, K.L., Reactive Extraction: An Intensifying Approach for Carboxylic Acid Separation. International Journal of Chemical Engineering and Applications, 3(4), pp Available at: Wiki Reactive Extraction Column version 4 9/2/17 8