Utilization of Supercritical Fluid Processing for Extraction and Purification Mike Favaloro Phasex
Contents Supercritical Fluid Process Description Some Applications Extraction of Monomers and Contaminants Polymer Fractionation Purification of Reactive Monomers Particle Formation Summary
Process Description What is a Supercritical Fluid? An SCF is any substance above its critical point Liquid-like dissolving properties Gas-like transport properties Small changes in P and T can change density and dissolving power of SCFs CO 2 is ideal because of it s low Tc & Pc FLUID T c, C P C, atm CO 2 31 73 H 2 O 374 218
Process Description Where are SCFs Used? SCFs Process Products that we use in daily life SCF Processing is used to Purify Medical Devices Extract Valuable Compounds Remove Impurities Create New Products Decaffeinate coffee and tea Herb and Spice Extracts Richer hops for brewing beer
Process Description Supercritical Fluids..Simplified Solubility starts to increase at Pc Solubility of a material is dependent on pressure
Solubility, wt% Concentration wt% Process Description Solubility of Naphthalene is Pressure Dependent All soluble compounds exhibit solubility behavior shown Pressure, MPa Temperature, C
Process Description SCF Extraction Process Dissolve solids in a gas Reduce pressure, solids come out as precipitate Re-use gas
Process Description Motivations for Examining SCF Eliminate solvent and contaminant residue Replace certain organic solvents Increase product performance Develop entirely new products
Process Description Why SCF vs Other Processes? No Residual Solvents When Compared to Solvent Extraction Process Preferable for internal medical devices and ingestible materials Highly Efficient Process for Purification Low Temperature When Compared to Steam Distillation Reduce or Eliminate Impact on Chemistry of Product Clean, Green Process
Applications Some Applications for SCF at Phasex POLYMERS (Purification, Fractionation) LOW VAPOR PRESSURE OILS (Volatility Control) SURFACTANTS (Purification) REACTIVE MONOMERS (Purification) NUTRACEUTICALS (Extraction and Concentration) TISSUE SCAFFOLDS (Purification)
Applications Extraction of Monomers and Contaminants from Polymers and High MW Oils SCF is an economic approach to this process Applications at Phasex Include Removal of volatiles from adhesives for high vacuum (Space) applications Removal cyclic and linear siloxanes from high MW siloxane polymers Purify polymers for internal medical applications Removal of Low MW Oligomers from Polyvinylsilane
Applications Polymer Fractionation SCF can fractionate polymers that cannot be separated by molecular distillation Narrow MW Fractionation is achievable Viable for solid and liquid polymers Process for Production of Narrow MW Fractions
Applications Purification of Reactive Monomers SCF can purify at low temperatures to very low impurity levels Vapor phase separation is not viable in many cases Low Temp prevents premature polymerization and degradation PDMS Contact Lens Macromonomer separated at 16 MPA and 60C Parent Purified Difunctional Impurity
Applications Controlled Particle Formation Polymer or organic material is dissolved in SCF Pressure is reduced and material precipitates at controlled particle size distribution Recrystallization of Beta-estradiol to controlled PSD
Applications Cannabidiol Extraction & Concentration CO2 extraction from hemp Achieve CBD concentration ~5-10% Hemp extract can be concentrated By distillation to ~35-40% max By CO2 to ~50-55% Further high pressure CO2 concentration Achieve ~85-90% CBD Can be xtallized directly to~100%
Summary The Supercritical Fluid Process is a valuable, yet underutilized tool for the materials engineer This enabling technology is being exploited for many commercial applications Nutraceuticals and dietary supplements Purification of medical polymers and implantable devices A significant database (35+ years) is available to support process and product development
Thank You! For further information and/or a free trial, contact Val Krukonis val@phasex4scf.com Mike Favaloro mike@phasex4scf.com