Aspen Model Documentation
•About This Process
•Physical Property Models and Data
•Selected Simulation Results: Blocks
PEP Process Module 1 19 Aug 1999
This Aspen Plus model simulates the production of acetic acid by low pressure methanol carbonylation in the presence of a heterogeneous rhodium (Rh) catalyst and the promoter methyl iodide. It is intended to resemble the Chiyoda/UOP Acetica™ process, a novel heterogeneous methanol process for the production of acetic acid. This technology is based on a heterogeneous Rh catalyst in which the active Rh complex is chemically immobilized on a polyvinylpyridine resin. In the Aspen Plus model, the plant (base case) is designed to produce 800 million lb/yr (363,000 t/yr) of acetic acid from methanol carbonylation. The process consists of both the carbonylation and purification sections. Results from the Aspen Plus simulation shows that the purity of acetic acid obtained is 98.4%. Vent gas (4,304 lb/hr) from two absorbers and heavy by-products (1,150 lb/hr) from the bottom of the heavy-ends stripper are sent to incinerator. The process also generates approximately 65,000 lb/hr of low-pressure (150 psig) steam that supplies a significant portion of the plant energy requirements.
PEP Process Module 2 19 Aug 1999
About This Process
Current global capacity for acetic acid exceeds 6.4 million t/yr. Downstream applications for the acid are primarily as a precursor for vinyl acetate monomer synthesis, for acetic anhydride production, and as a solvent in purified terephthalic acid production. Methanol carbonylation to produce acetic acid using a homogeneous Rh catalyst accounts for more than 55% of global capacity,...