Which of the following reaction is NOT a step in the formation of sodium chloride

Aspirin (3) was synthesized by esterification reaction of salicylic acid (1) with acetic anhydride (2) catalyzed by aluminum dihydrogen tripolyphosphate/loaded sulfur diatomite. The effects of materials ratio[r = n (2) ∶ n (1) ], reaction time, temperature and catalyst amount on the yield of 3were investigated by the single-factor experiments. The results showed that the four main factors influencing the yield of 3 are in the following order: r reaction time reaction temperature catalyst amount. Under the optimum reaction conditions[1 was 50 mmol, the catalyst amount was 5%, r was3. 14, at 81 ℃ for 40 min], the yield was 88. 6%. The yield still reach 83. 3% after reuse for five times of the catalyst