Through a combination of Lurgi and Nippon Kayaku technology, Air Liquide Engineering & Construction enables customers to produce ester-grade acrylic acid (EAA), which is most frequently used in adhesives, paints and coatings as well as in diaper production. The process delivers high acrylic acid yields and a long onstream time. Raw material and energy consumption rates are low, and the impact on the environment is minimal.
Catalyzed oxidation of propylene
The process involves a two-stage tubular fixed-bed reactor system that produces acrylic acid (AA) through the catalyzed partial oxidation of propylene. Heat from the reaction is used to produce steam, and the reactors are maintained at a safe temperature by circulating molten heat transfer salt.
The product gas from the reactor is then sent to a quench tower, where the AA is recovered and AA solution is routed to an extractor. Further AA is recovered from uncondensed gases in an offgas treater, while overhead gas is recycled back to the first reactor.
In the next step, liquid-liquid extraction is used to separate water from the AA. This results in crude AA, which is passed further into two columns to remove the solvent and acetic acid. Finally, the crude AA is purified in an Ester grade AA column, delivering an extremely pure acrylic acid.
Throughout the entire process, a raffinate stripper is used to recover and recycle solvents from the waste water streams. This is one of the numerous cost and performance benefits offered by the solution.
Raw material and energy consumption is low, while onstream time and catalyst longevity is high. Furthermore, the process is environmentally-friendly and offers the benefit of relatively low production costs.
As acrylic acid is prone to polymerization, an inhibitor control system is installed at critical points in the plants.
Produces ester-grade acrylic acid from propylene
Low impact on the environment
High performance catalysts have outstanding longevity
Low energy and raw material requirements
Long onstream time
Competitive production costs
Capacity: up to 20 tons per hour (single reactor train)