抄録
Phosphoric acid transfer phenomena along new or used porous carbon plates were investigated. Two adjacent 15cm sections of a 30cm porous carbon plate were filled with 105% phosphoric acid to different fill levels, kept at 180°C for between 2_??_85 hours and acid transfer from the acid-rich portion to the acid-poor portion was measured. Whereas a uniform decrease in the acid fill levels of the acid-rich portion was observed, unbalanced distributions of acid fill levels were observed in the acid-poor portion. The acid stopped to move within 24 hours despite the unbalanced distribution of acid fill levels in the acid-poor portion. As the initial fill levels of both portions decreased, the slope of the acid-poor portion fill level became steep. When the acid fill level in the acid-rich portion decreased below 30% in this used porous carbon, the acid showed no transfer. The slope of acid-poor portion fill level in new porous carbon plates was steeper than that of used porous carbon plates. These limitations on acid transfer can be explained by the difference between the forward and backward wetting angles on the acid/carbon materials boundary.
