Study on Extraction Mechanism of Oxalic Acid by TOA

摘要

Water-oxalic acid-TOA (n-octanol+ kerosene) was used as the experimentla system, TOA, n-octanol and kerosene as complexing agent, diluent and modifier respectively. The extraction mechanism of oxalic acid by TOA and influence of the concentration of TOA and solute on extraction equilibrium were investigated. The complex structure in the organic phase was measured by infrared spectroscopy, and that there are two types of compelxes in the orgnaic phase, 1:1 and 1:2 (acid: TOA) was proved. The models were proposed, and the reactive equilibrium constant, K_11 and K_12 were obtained by fitting the experimental data, where K_11 was much larger than K_12.