Improved Method for the Production of Tetrahydrofuran From Biomass
Statement of the Problem: Tetrahydrofuran (THF) is a large volume, commodity chemical used as a basic building block for polyurethane stretch fibers (Spandex), other elastomers, solvents for PVC cements, pharmaceuticals, and coatings. Current THF production requires petroleum-based raw materials and significant energy inputs, representing inefficient use of petroleum resources and placing the U.S. at a manufacturing disadvantage compared to chemical manufacturers in other world areas. Pulp and paper manufacture is one of the largest industries in the U.S., representing about 6% of the manufacturing sector of the U.S. GDP. In recent decades, the pulp and paper industry has struggled with a declining market, poor profitability, and competition from other world areas, leading to the shutdown of many U.S. pulp and paper mills, and loss of U.S. employment. The production of chemicals, such as THF from pulp and paper waste hydrolysate, can provide new technologies and products from pulp and paper manufacture which can enhance industry profitability. The iCARD technology will produce and sell THF from selected pulp and paper byproduct hydrolysates without deleterious effect on ongoing pulp production of the mill. Overall Objective: The overall goal of this Small Business Innovation Research Phase II Project was to complete the research, development, and design tasks required to commercialize an innovative technology using catalytic reactive distillation to achieve process intensification for the manufacture of “green” THF from pulp mill waste hydrolysate. The new technology will benefit the U.S. pulp and paper industry by providing new technologies and products from pulp and paper manufacture, which can enhance industry profitability, and increase industry employment. Development of commercially competitive biomass based technologies will reduce consumption of scarce hydrocarbon resources, and improve long term U.S. competitiveness in global markets. Conclusions: The novel catalytic reactive distillation technology successfully demonstrated the technical and economic feasibility of the manufacture of THF production from dilute aqueous biomass solutions. New catalyst compositions were developed with catalytic activity for conversion of furfural to THF which exceed the activity of conventional catalysts by 2 to 3 orders of magnitude. The feasibility of achieving selectivity to the desired THF product approaching 100% was demonstrated. The novel catalysts also demonstrated catalyst stability far superior to conventional furfural decarbonylation catalysts. The novel technology also demonstrated the ability to produce other valuable commercial products such as tetrahydrofurfuryl alcohol, 1,5-pentanediol, 2-methyl furan, and 2-tetrahydromethylfuran as co-products with THF. Based on the use of waste pulp mill hydrolysate as the biomass raw material source, the new technology will produce THF for a total manufacturing cost less than the raw material cost for the hydrocarbon-based feed stocks for conventional THF production. Commercial Applications: Selective catalytic reactive distillation of pulp mill waste hydrolysate will allow commercial production of “green” THF from biomass feedstocks for the production of “green” elastomer fibers, and industrial solvents. The new technology will benefit the U.S. pulp and paper industry by providing new technologies and products from pulp and paper manufacture, which can enhance industry profitability, and increase industry employment. Development of commercially competitive biomass based technologies will reduce consumption of scarce hydrocarbon resources, and improve long term U.S. competitiveness in global markets.