MOLASSES 449 



Dubrunfaut 7 was the first technicist to use these processes. He mixed 

 a hot saturated solution of baryta with molasses at 30 Baume. The 

 resulting saccharate which formed at once was washed with cold water, 

 suspended in water, and decomposed by a current of carbon dioxide. After 

 filtering off the insoluble barium carbonate a liquor of 98 to 99 purity was 

 obtained. A sample of sugar thus made obtained a Council gold medal 

 at the Great Exhibition of 1851. Difficulty in regenerating the barium has 

 prevented the extension of this process, which, however, still remains in 

 limited use. 



Following on Dubrunfaut 's work, Scheibler, Seyferth and Manoury, 

 all working about 1870, developed the schemes known as elution processes. 

 In these, milk-of-lime or dry lime was mixed intimately with undiluted 

 molasses. An impure saccharate resulted, which was purified by washing 

 with alcohol afterwards recovered. 



A somewhat similar process is the sucro-carbonate process of Boivin 

 and Loiseau, 9 in which a current of carbon dioxide is passed through a paste 

 obtained on intimatelyjnixing lime and molasses. The sugar is precipitated 

 as a complex lime-sucro-carbonate, which after washing is suspended in 

 water and broken up by further passage of carbon dioxide. 



The use of strontia was patented by F. Jiinemann Pierre de Rieu in 

 1866, and it was used in a secret process about this time in Germany. The 

 credit of making the process technically successful is due to Scheibler, 

 who devised two schemes. In the bibasic process 10 three equivalents of 

 strontia to one of sugar are mixed with hot dilute molasses. The saccharate 

 that forms is separated from the mother liquor by filtration and washed 

 with a 10 per cent, solution of strontia. In order to decompose the saccharate 

 it is placed in vessels set up in a battery, through which is passed a 2 per cent, 

 solution of strontia at a temperature of from 4 to 15 C. The bibasic 

 saccharate is decomposed into the monobasic body and strontia, the whole 

 operation taking forty-eight hours. The monobasic saccharate is decom- 

 posed by carbonation and the strontia used in the next series. In the mono- 

 basic process 11 a solution of strontia is mixed with molasses, the temperature 

 not being allowed to rise above 20 C. The monobasic saccharate which 

 forms is separated by nitration and decomposed by carbonation. 



The strontia process due to the Austrian, Steffen, is known as the sub- 

 stitution process. 12 The five operations in the cycle of this scheme are : 



1. Formation of a soluble bibasic saccharate in the cold. 



2. Transformation of the bibasic saccharate into sugar and insoluble 

 tribasic saccharate by boiling. 



3. Separation by filtration of the tribasic saccharate. 



4. Regeneration of the mother liquors by the addition of fresh molasses. 



5. Periodic reduction of the mother liquors. 



In outline the different processes are worked as follows : 



1. Molasses diluted to n-i2 Brix are mixed with continued agitation 

 with powdered quicklime in the proportion of one part of sugar to one of 

 lime. The mixture is then filtered to remove scums. 



2. The filtrate is heated in autoclaves to a temperature of io5-iio C. 



3. The tribasic saccharate formed on heating is filtered, the cakes washed 

 with boiling water, and the saccharate used instead of lime in the treatment 

 of the raw juice. 



4. The mother liquors coming from the filtration of the saccharate are 

 used to dilute a further portion of molasses. 



2H 



