The overall focus of this application is to develop nanofiltration membranes to recover the spent solvents generated from drug manufacturing processes allowing the solvents to be reused resulting in elimination of waste. This is also responsive to NIH RFP PA-09-100 entitled """"""""Energy Efficiency and Renewable Energy System Technology Research &Development"""""""". By using a pressure-driven nanofiltration versus a thermal-driven separation such as distillation for recovery of pharmaceutical spent solvents, we also are directly responsive to this NIH's RFP for energy efficient processes. Chemical syntheses in the pharmaceutical industry are often carried out in solvents and generate large amount of spent solvents. Extraction and purification of pharmaceutical ingredients and cleaning of the drug manufacturing equipment such as reactors also generate solvent effluents. There are numerous needs in the pharmaceutical industry that involve the treatment of these organic solvents. They include: i) production of high purity solvents for organic synthesis ii) recovery of spent organic solvents to reduce the amount of toxic waste produced. The current application is addressed to remove contaminants from spent organic solvents generated from the production of bulk pharmaceutical substances. Nanofiltration separation, driven by the applied pressure gradient, allows solvents to permeate selectively through the membrane retaining the solutes and non-selective solvents. Most of the waste solvents produced in the drug manufacturing processes contain low molecular compounds or solutes such as spent catalysts and by-products with molecular weight less than 1000 g/mol. The spent solvents often contain azeotropic solvent mixtures that can not be separated easily.
This project will develop a membrane product and process to remove dissolved oxygen and water from reaction solvents and reactants as well as unreacted chemicals, spent catalysts and byproducts from spent organic solvents. This development has considerable significance to reduce production costs related to pharmaceutical manufacturing.