PREPARATION  OF  ALUMINIUM,  SODIUM,  ETC. 
417 
PREPARATION  OF  ALUMINIUM,  SODIUM,  CHLORIDE  OF  ALUMI- 
NIUM, ETC. 
Mr.  Deville  has  just  published  a  detailed  account  of  the  ex- 
periments with  which  he  has  been  engaged  for  some  time,  with 
reference  to  the  production  of  aluminium,  in  such  a  state,  and 
at  such  a  cost,  as  to  be  practically  applicable  for  various  purpo- 
ses in  the  arts. 
The  method  that  he  adopted  is  essentially  the  same  as  that 
by  which  Mr.  Wohler  obtained  this  metal — the  decomposition  of 
chloride  of  aluminium  by  means  of  an  alkaline  metal.  Sodium 
was  chosen  as  the  decomposing  agent,  because  it  is  more  easily 
obtained  than  potassium. 
The  apparatus  used  is  represented  by  fig.  1.  It  consists  of 
three  cylinders  A,  B,  D,  connected  by  tubes  Y,  C,  and  heated 
by  furnaces  F,  G. 
Fig.  l. 
The  chloride  of  aluminium  is  introduced  into  the  cylinder  A  ; 
the  sodium  is  placed  in  trays,  holding  about  ten  pounds  each9 
within  the  cast  iron  cylinder  D.  The  intermediate  cylinder,  E, 
contains  about  a  hundred  weight  of  scrap  iron,  which  serves  to 
separate  iron  from  the  vapor  of  chloride  of  aluminium,  by  con- 
verting the  perchloride  of  iron  into  the  much  less  volatile  proto- 
chloride ;  it  also  separates  hydrochloric  acid  and  chloride  of 
sulphur. 
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