646 SEC. 13. CHEMISTRY. 



From the appended analysis by Kopp of a sample it will be seen that a 



large quantity of sulphur is present in the waste. A part of this can be 

 profitably extracted by Mond's and other processes. 



Sulphide of sodium - 2,880 



Carbonate of lime - - 13,630 



Silicate of lime - - 5,680 



Hydrate of lime - 8,588 



Monosulphide of calcium - 22,162 



Alumina, magnesia - 1,466 



Sulphide of iron - - - 2,670 



Carbon - - 1,800 



Sand - - 2,000 



Water - - 36,700 



Combined water and loss - 2,418 



2478. Oxidized Soda, Alkali, or Vat Waste. 



John Hutchinson fy Co. 



In Mond's process a current of air at the ordinary temperature is forced 

 through the waste as it lies in the vats, directly the last soda liquors are 

 drained away. The waste becomes hot, oxydizing, and forming polysulphides 

 of calcium, hyposulphite and hydrosulphate of calcium. The waste is then 

 lixiviated, and the liquid removed, the residue being again treated as above 

 several times. 



2479. Sulphur Liquor, the soluble portion of Oxidized 

 Alkali, or Tank Waste. John Hutchinson fy Co. 



The oxydized waste, lixiviated in the vats with warm water, gives a yellow 

 solution containing polysulphides of calcium, hyposulphite of calcium, and 

 hydrosulphate of calcium. 



Liquor generally contains equal to 5 '0 of sulphur, distributed as follows: 

 2 ' hyposulphite of calcium. 

 2 polysulphide do. 

 1 hydrosulphate do. 



2480. Precipitated Sulphur, formed when sulphur liquor 

 and muriatic acid are mixed. John Hutchinson fy Co. 



Sulphur liquor is mixed with common hydrochloric acid from the con- 

 densers, the mixed liquors being heated to 140 Fahr. and well stirred. 



The muriatic acid forming chloride of calcium in the liquor, sulphur is 

 deposited as a yellow flocculent precipitate. 



In a good sample of liquor all the sulphide of hydrogen disengaged by 

 decomposition of the sulphides reacts on the sulphurous acid liberated at the 

 same time from the hyposulphite, sulphur and water being the products. 



2481. Lump Sulphur, prepared by melting the moist 

 sulphur of a previous stage of the process in a strong cast-iron 

 vessel. John Hutchinson S>* Co 4 



After washing out the chloride of calcium from the moist sulphur, the 

 drained product is put into a strong cast-iron cylinder, the filling-in aperture 

 screwed down, and steam of a pressure of 35 Ibs. admitted through a coil of 

 cast-iron pipe. The sulphur rapidly melts, and at the expiration of a certain 

 time, found out by experience, the whole charge is forced by the pressure of 

 the steam through the discharge pipe into tight wooden wagons, and when 

 cool broken up for sale. 



