Methanol–HCl can also be prepared by adding concentrated sulfuric acid drop-wise to sodium chloride.The hydrogen chloride fumes generated should be absorbed in a solution of acetic anhydride and anhydrous MeOH [52]. Alternatively, liquid acetyl chloride can be added to anhydrous MeOH [293], if methyl acetate does not interfere with the analysis. The preparation of an alcoholic solution of HCl is given in detail by Darbre [294]. A mixture of n-butanol–H2SO4 has also been used [295]. The reaction is AAC1 mechanism (see Fig. 17).