A 2-lon-per-day continuous pilot plant has demonstrated conclusively the chemical and mechanical feasibility of a process for iron-free alum production. Under optimum conditions of operation, an alcohol loss of 0.43% is realized. The estimated production cost of 839.91 per ton of alum in a commercial 20-ton-per-day plant indicates that, under present market conditions, the process would not be economically feasible. The basic significance of the process lies in the fact that an expensive organic chemical can, by proper engineering design, be utilized to produce a