MOLASSES 



451 



in the other, are small channels establishing communication with the interior 

 of the frame. If, then, water enters at B and molasses at D, the water will 

 flow along the canal formed by the openings B and into the interior of the 

 frames by the channels h, and the molasses will similarly flow- by way of D 

 and d ' . The water \vill discharge itself along the canal formed by the open- 

 ings C and c, and the molasses along that formed by the openings A ' and a ' . 

 There is thus a continual flow of molasses and water separated by a sheet of 

 parchment. The water which leaves the apparatus now charged with a 

 proportion of molasses is called water of exosmose, and it contains roughly 

 about half the salts originally present in the molasses. Although this 

 process has been largely used in times past and is still to a certain extent 

 employed in beet sugar factories, it is financially unsuccessful ; the large 

 size of the osmogenes required (500 square feet diffusion surface only being 

 sufiicient to treat three tons of molasses in twent3^-four hours) the extreme 

 dilution of the osmosed molasses, the expense of evaporation, and the small 

 extra jdeld of sugar, entirely discounting the monetan.' value of the process. 



Fig. 2- 



Precipitation Processes. — In Margueritte's process^' molasses was first 

 purified from " gums " and a part of the salts and then treated with a large 

 excess of alcohol, which was afterwards recovered. 



Glacial acetic acid is another precipitant of sugar ; its use has been 

 proposed b}' Wernicke and Pfitzinger.^^ The wxiter does not beheve that 

 this process has ever been used on the commercial scale. 



The Disposal of Molasses. By sale as such. — In certain places the sale 

 of molasses to distillers or for direct consimiption forms a pai t of the routine ; 

 in some cases, particularh^ in the muscovado process followed in Barbados, 

 this procedure is very profitable since fancy prices are still to be obtained 

 for these grades of molasses. Considered from the point of view of the 

 agricultural chemist, nothing can be said in favour of this scheme as it entails 

 the absolute removal from the soil of much valuable plant food, particularly 

 in the form of potash. With the very pure juices found in the Hawaiian 

 Islands the molasses amount to about 20 per cent, of the sugar shipped, 

 a figure rising to as much as 40 per cent, in the case of the impure juices 

 found in Demerara, and elsewhere ; molasses on an average contains about 

 4 per cent, of potash, so that the sale of the molasses implies the removal 

 from the soil of from 18 to 36 lbs. potash per ton of sugar shipped. 



