Propane-to-acrylic acid

Abstract

Acrylic acid is an essential polymer raw material for many industrial and consumer products. Currently, acrylic acid is manufactured from propylene, which is created as a byproduct from fossil fuels manufacture and industrial cracking of heavy hydrocarbons. However, the discovery of new natural gas reserves presents new opportunities for the production of acrylic acid. A design feasibility study is presented to analyze the economics behind producing acrylic acid from the selective oxidation of propane to propylene over a mixed metal oxide catalyst, Mo1V0.30Te0.23Nb0.125Ox. The proposed plant is located in the U.S. Gulf Coast and produces 200MM lb/yr acrylic acid. Since the catalytic oxidation process has low propane conversion per pass, the process recycles unconverted propane and propylene back to the reactor to increase overall conversion. The acrylic acid is then separated and purified to the glacial-grade industrial standard for polymer raw material of 99.7% acrylic acid by mass. A major challenge of the separation process is the non-ideal behavior of the components, which produces three different azeotropes: water with acrylic acid, water with acetic acid, and acetic acid with acrylic acid. The separation process utilizes four distillation towers to navigate around the azeotropes. After a thorough economic analysis, the proposed process is found to be economically viable. It has an estimated IRR of 84.9% and NPV of $384,963,400 at a 15% discount rate using an acrylic acid price of $1.75/ lb. The process is predicted to become profitable in year 3. If the product price decreases by 45% to $1.20/lb (the current market price of acrylic acid), the estimated IRR will be 45% with a NPV of $114,552,700 at a 15% discount rate. The process will then become profitable in year 4. Disciplines Biochemical and Biomolecular Engineering | Chemical Engineering | Engineering This working paper is available at ScholarlyCommons: http://repository.upenn.edu/cbe_sdr/48 Department of Chemical & Biomolecular Engineering Senior Design Reports (CBE) University of Pennsylvania Year 2013 Propane to Acrylic Acid Amanda Culp University of Pennsylvania Kevin Holmes University of Pennsylvania Rohan Nagrath University of Pennsylvania Dan Nessenson University of Pennsylvania Propane to Acrylic Acid Amanda Culp |Kevin Holmes| Rohan Nagrath |Dan Nessenson School of Engineering and Applied Science University of Pennsylvania April 9, 2013 Advisor: Dr. John Vohs Primary Consultant: Bruce M. Vrana University of Pennsylvania Department of Chemical and Biomolecular Engineering 220 South 33 rd Street Philadelphia, PA 19104 April 9 th , 2013 Dear Dr. Vohs and Professor Fabiano, Enclosed you will find the proposed process design for the industrial production of acrylic acid as a solution to the design problem presented by Bruce Vrana of DuPont. The proposed design uses a mixed metal oxide catalyst, Mo1V0.30Te0.23Nb0.125Ox, in a fixed bed reactor to selectively oxidize propane to acrylic acid using propylene and acrolein inermediates. The product is separated using a flash distillation column from leftover starting materials, which are recycled back to the reactor. Then, the acrylic acid is purified from water, acetic acid, and trace amounts of unreacted materials using four distillation towers. The proposed plant will be constructed in the U.S. Gulf Coast and will produce 200 MM lb/year of industrial-grade acrylic acid. This report contains a detailed process design, an economic analysis, and conclusions and recommendations for the implementation of the plant. The proposed process is found to be viable and economically profitable with an estimated IRR of 84.9% with a total NPV of $384,963,400 at a discount rate of 15%. The process was modeled using AspenTech Plus v7.3. Economic analysis and equipment sizing was conducted using Aspen IPE and Aspen Economic Evaluation v7.3 along with the equations spreadsheets contained in Process Design Principles, 3 rd Edition, by Seider, Seader, Lewin and Widagdo. Thank you for your assistance with this project.