TECHNOLOGY FOR THE PRODUCTION OF DI-OCTYL PHTHALATE AND OTHER PLASTICIZERS
PROCESS FEATURES
CONSER offers a highly reliable and advanced technology for the production of di-octyl phthalate (DOP) practised in plants of the SISAS group.
The process uses a metal based catalyst which has brought huge benefits compared to the conventional process using a strong acid based catalyst.
The high selectivity of the catalyst has practically emiminated the formation of by products, making unnecessary any purge in the recycle of the excess alcohol.
No neutralization or washing steps of the product are necessary and the problems of waste management are substantially reduced.
The product meets high standards of colour, and decoloration is not necessary.
Know how can be supplied also for the production of other plasticizers, as dibutyl phthalate and maleate, diisobutylphthalate, dimethyl and diethyl phthalate, dimethylsuccinate, dioctylmaleate, etc.
REFERENCES
Location SISAS-CHEMICAL Italy PANTOCHIM Belgium 100000 EUROFTAL Belgium 70000
PROCESS DESCRIPTION
The technology offered by CONSER is based on the following main steps:
• Reaction
• Distillation
• Filtration
Reaction
The process may use a batch reaction section coupled with a continuous purification section or, in alternative, may be based on a fully continuous operation.
The main advantage of the batch reaction is the flexibility in operation, while the continuous process, making easier the process control, is preferred for high capacity plants.
The reaction takes place in two steps:
1) PA+2-EH ------------------> Monoester
2) Monoester + 2 EH ------------------> DOP + H2O
During the reaction a mixture of water and alcohol is distilled and the alcohol returnsto the reactor after phase separation.
At the end of the reaction excess alcohol is distilled by decreasing the pressure, at the same time the product is cooled.
Distillation
The raw product is fed to a column in which live steam is injected to remove all the remaining octanol as well as any other light component. The vapour steam is condensed and the organic phase is collected for recycling.
An additional column helps drying the ester.
Filtration
The filtration section completely removes the catalyst from the mixture, which can be sent directly to the product storage tanks.
No treatment for decoloration is required on the product.
