Carbon Dioxide → Terephthalic Acid

Participants

Reaction Conditions

Reaction Steps

In a heated autoclave, provided with a mixer and filled partially with water, disintegrated poly/ethyleneterephtalate/ wastes in a form of scraps of bottles and textiles were placed in the amount of 1000 g together with a solution of 1043 g of potassium bicarbonate (KHCO3) in 10 liters of water, and then a content of the reactor was heated up to 190° C. and the temperature was kept till the digestion of poly/ethylene terephtalate/ was completed and the formation of carbon dioxide was stopped. Then the autoclave was relieved and carbon dioxide was separated, and a resulted solution was filtered hot through a filter with active carbon. The filtrate was neutralised with orthophosphoric acid and a precipitate of terephtalic acid was separated from a reaction solution using a centrifuge. The resulted product was washed with a distilled water and crystallised from water, giving 864,2 g of terephtalic acid. At the same time ethylene glycol was separated from the neutralised filtrate using distillation, obtaining 322,5 g of ethylene glycol and almost theoretical amount of inorganic salt.

Provenance & Evidence