In analogy to extraction of bulky organic acids by normal amines, strong temperature effects were predicted for extraction of strong mineral acids (of small molecular size) by bulky amines. Extractants, chosen according to analysis in previous papers, were found to show the required effect and thereby provide the basis for “temperature swing” LLX process for recovery and concentration of acids from dilute solutions. Diluent/modifier effects were utilized for the adjustment of extractant properties and maximizing temperature effect.