[mclean] 



ADSORPTION OF GASES 



195 



3. Test of Possible Chemical Combination of 

 Lignite and Gases 



To find out whether any chemical action or permanent adsorption 

 takes place, the apparatus shown in Fig. 5 was set up. Five samples 

 of lignite carbonised at different temperatures were put in the tubes 

 at Z. These samples were: raw lignite and lignite carbonised at 

 105°C., 350°C., 450°C. and 550°C. They had not been exposed to 

 the air since carbonisation except where they were transferred to 

 these tubes and then they were immediately heated to their respec- 

 tive temperatures and each tube exhausted. 



The weight of each tube was found and the lignite exposed to 

 the gas for a time sufficient for saturation to take place. The tubes 

 were then weighed, heated out, exhausted and weighed again. If 

 the last weight was appreciably different from the first, then chemical 

 action or permanent adsorption must be taking place. 



Readings were made for three gases: dry nitrogen, dry oxygen 

 and moist oxygen. The results are given in Tables VII, VIII and IX. 

 In the first column is given the temperature at which the lignite was 

 carbonised; column 2 gives the net weight of the lignite and column 

 3 the weight after the lignite was saturated with the gas at atmos- 

 pheric pressure, the difference denoting the gas absorbed is given in 

 the next column. Column 5 repeats column 2, and column 6 gives the 

 final net weight of the lignite after it had been heated and exhausted. 

 The last column gives the difference between the initial and final 

 weights of the. samples, and consequently shows the net gain or loss 

 in weight during the whole operation. 



Table VII 



Dry Nitrogen 



