IODINE AND OTHER CHEMICALS 69 



During the World War the shortage of acetone 

 and other organic solvents suitable for use in the 

 manufacture of smokeless powder was acute. The 

 Hercules Powder Company endeavored to partially 

 fill their own requirements by manufacturing cal- 

 cium acetate and acetone from kelp. This was car- 

 ried out at San Diego on a tremendous scale by an 

 ingenious process involving the fermentation of 

 the kelp and the separation of the fermentation 

 products. 



The process involved the following steps: The 

 macerated kelp was brought to the plant in barges, 

 from which it was pumped by rotary pumps to large 

 redwood tanks, where it was diluted and allowed to 

 ferment under the proper conditions of temperature 

 and acidity. About 150 tanks of 50,000 gallons 

 capacity each were required to hold the enormous 

 amount of kelp which was harvested. After two 

 weeks practically all of the kelp was in solution. The 

 solution was then filtered and evaporated. As the 

 evaporation proceeded, a mixture of calcium acetate, 

 propionate, and butyrate separated; then calcium 

 acetate and potassium chloride crystallized succes- 

 sively. Iodine was obtained from the mother liquor. 



The products of this remarkable process included 

 potassium chloride, acetone, acetone oils, organic 

 esters and acids, iodine, algin, and common salt. 

 Acetone and certain mixed ketones, which possess 

 much value as solvents for the smokeless powders 

 and airplane dopes, were obtained by heating the 

 calcium acetate in retorts. Algin or alginic acid was 

 obtained from the leaves of the kelp which remain 



