METHOD OF NEUTRALIZING WASTE DEVELOPING SOLUTION CONTAINING TETRAALKYLAMMONIUM HYDROXIDE

摘要

A method of neutralizing a waste developing solution which contains a tetraalkylammonium hydroxide and further contains, dissolved therein, an organic substance derived from a photoresist, by bringing the waste developing solution into countercurrent contact with carbon dioxide or a gas containing carbon dioxide in a neutralization column. In the method, bubbles generating in the neutralization column can be effectively removed without accumulating in the neutralization column. In this neutralization method, bubbles generating in a gas-phase part at the top of the neutralization column during the neutralization of the waste developing solution are taken out of the column and brought into contact with a heater to eliminate the bubbles.