298 CHAPTER XVI 



The influence of the particular acid used to obtain acidity was found 

 to be neghgible. The indicator used in this experiment is not specified. 



Zerban^^ has, too, recently operated on large-scale experiments with 

 Norit in combination with kieselguhr, and in the absence of lime treatment. 

 He obtained normal working, and observed very great adsorption of pectins 

 (alcoholic precipitate) and very small adsorption of ash. 



These vegetable carbons are recommended for use in quantity greater 

 than necessary for decolorization, the material being used repeatedly until 

 ineffective, when revivification is necessary. The quantity stated to be 

 used is 5 per cent, on dry substance, used ten times in succession. Partial 

 revivification is effected by washing with sodium carbonate, but eventually 

 a heat treatment is required. 



These carbons have not yet come into standard practice. They have 

 been used to some extent in refineries in Scotland, Holland and Portugal, by 

 some confectioners on a minor scale, and in isolated cases in raw sugar houses 

 in Java and Mozambique and Louisiana. A material due to Peck and Lyon, 

 and prepared by the action of sulphuric acid on molasses absorbed by 

 kieselguhr, is also in use in at least one house in Hawaii. 



Other Agents. — In addition to those already quoted may be mentioned 

 hypochlorites, chlorine, ozone. Von Lippmann^^ j^^s made a complete 

 collation of all the proposals which may most conveniently be read in the 

 fifth edition of Spencer's " Handbook for Cane Sugar Manufacturers." 

 Other than those mentioned above, none is of importance. 



REFERENCES IN CHAPTER XVI. 



1. La. Ex. Sta., Bull. 157. 



2. " Practical White Sugar Manufacture," London, 1915. 



3. Jour, de Phys., 1810, 71, 455. 



4. Ann. Chim. Phys., 1849, 27, 273. 



5. La. Ex. Sta., Bull. 91. 



6. S.C., 1897, 29, 346. 



7. Jour. Ind. Eng. Chem., 1919, 11, 157. 



8. Int. Sug. Jour., 1918, 20, 191. 



9. Int. Sug. Jour., 1918, 20, 309. 



10. Jour. Soc. Chem. Ind., 1919, 38, 396 T. 



11. La. Bull. 173. 



12. Deut. Zuckerind., 1909, 34, 9. 



