ON  THE  PURIFICATION  OF  ANTIMONY. 
65 
Liebig's  process,  to  which  some  authors  give  the  preference,  is 
as  follows  : — 
Sixteen  parts  of  metallic  antimony  are  mixed  with  one  part  of 
sulphuret  of  antimony  and  two  parts  of  dry  carbonate  of  soda, 
and  the  mixture  fused  in  a  Hessian  crucible.  The  button  of 
metal  which  results  is  powdered,  then  fused  with  one-and-a-half 
part  of  carbonate  of  soda,  and  the  product  of  this  operation  is 
again  powdered  and  fused  a  third  time  with  one  part  of  carbonate 
of  soda. 
I  have  found  that  this  process,  which  in  practice  is  rather 
tedious,  does  not  answer  well  if  the  antimony  contains  much  of 
the  foreign  metals.  It  is  also  subject  to  the  objection  that  it  is 
not  economical,  as  during  the  three  successive  fusions,  much  of 
the  antimony  is  lost  in  the  scoria  which  is  rejected.  Moreover, 
Mosander,  Berzelius,  Berlin,  Bucholz,  and  TrommsdorfF  assert 
that  they  have  always  found  arsenic,  even  after  fusing  the  metal 
many  times  with  carbonate  of  soda. 
I  have  endeavored  to  ascertain  whether  a  more  satisfactory 
result  may  not  be  obtained  by  substituting  a  wet  process  for  the 
dry  process.  In  fact,  I  have  found  that,  by  converting  the 
antimony  into  antimonic  acid  by  means  of  nitric  acid,  it  is  pos- 
sible not  only  to  dissolve  all  the  arsenic  in  the  state  of  arsenious 
acid,  but  also  to  convert  the  lead,  bismuth,  and  iron,  into  soluble 
nitrates. 
The  following  is  the  process  I  adopt  :— 
Into  a  porcelain  capsule  of  large  capacity  placed  under  a 
chimney,  I  put  500  grammes  of  commercial  nitric  acid,  and  add, 
in  small  quantities  at  a  time,  250  grammes  of  metallic  antimony 
reduced  to  a  fine  powder.  Each  addition  of  metal  causes  the 
disengagement  of  abundance  of  nitrous  fumes.  All  the  antimony 
passes  to  the  state  of  insoluble  antimoniate  of  antimony,  which 
is  quite  white,  while  the  foreign  matters  remain  in  solution  in  the 
supernatant  liquor.  The  product  of  this  operation  is  thrown  into 
a  large  precipitating  vessel  and  washed  several  times  by  decan- 
tation,  with  water  containing  one  per  cent,  of  nitric  acid.  After 
eight  or  ten  successive  washings,  the  deposit  is  drained  as  much 
as  possible,  and  then  mixed  with  thirty  or  forty  grammes  of 
powdered  sugar.    The  resulting  paste  is  put  into  a  Hessian 
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