Am^Jo^r  Pharm.|  Notes  on  the  Soda  Industry.  1 1 
NOTES  ON  THE  SODA  INDUSTRY. 
By  A.  Scheurer-Kestner. 
I.  Loss  of  Sodium  in  the  Le  Blanc  Process. — Eleven  years  ago  the 
author  established  that  the  loss  of  sodium  experienced  in  the  Le  Blanc 
process  is  proportional  to  the  quantity  of  chalk  employed.  It  is  thus 
to  the  interest  of  the  manufacturer  to  avoid  excess  of  chalk,  but  at  the 
same  time  to  use  a  quantity  sufficient  to  ensure  perfect  whiteness  of 
the  finished  product.  The  author  put  forward  the  hypothesis  that  the 
loss  is  occasioned  by  the  formation  of  a  sparingly  soluble  calcium- 
sodium  carbonate;  this  view  has  been  confirmed  by  the  researches  of 
Jurisch,  Watson  Smith,  and  Liddle  and  Reidemeister.  The  latter  has 
found  in  the  lixiviating  vats  crystals  of  the  composition  of  gaylussite, 
Na2C03,CaC03,5II20,  a  compound  insoluble  in  sodium  carbonate  and 
hydrate,  mixed  in  the  proportion  in  which  they  occur  in  the  crude  lye; 
it  dissolves  slowly  in  water,  the  crystals  becoming  opaque  from  the 
ready  dissolution  of  the  sodium  carbonate. 
Reidemeister  has  further  shown  that  gaylussite  is  formed  not  only 
in  the  lixiviating  vats,  but  also  in  the  anhydrous  state  in  the  soda 
pans  during  fusion;  it  probably  also  occurs  in  the  residues,  and  the 
deposit  of  the  caustification  process,  but  its  state  of  division  prevents 
its  detection  and  isolation. 
II.  Presence  of  Vanadium,  Fluorine,  and  Phosphorus  in  Crude  Soda- 
lyes. — In  1864  Rammelsberg  detected  the  presence  of  vanadium  and 
of  sodium  phosphate,  Na3PO4,10H2O,  in  crude  soda-lyes ;  Baumgarten, 
a  short  time  after,  found  fluorine  existing  as  a  double  sodium  phos- 
phate and  fluoride,  NaF2Na2P04, 1 8H20.  From  the  red  mother-liquors 
in  the  manufacture  of  the  carbonate  and  hydroxide,  Rammelsberg 
separated  crystals,  either  white,  or  red  from  the  presence  of  iron, 
which  proved  on  analysis  to  be  identical  with  Baumgarten's  compound; 
they  also  contained  about  1*2  percent,  of  vanadicacid.  It  is  probable 
that  the  chalk  and  coal  furnish  the  vanadium  and  phosphorus ;  the 
origin  of  the  fluorine  is  quite  uncertain. 
III.  Loss  of  Sodium  in  Caustification. — The  author  has  previously 
shown  that  the  loss  of  sodium  in  caustification  arises  from  the  same 
cause  as  the  loss  of  sodium  in  the  Le  Blanc  process,  i.e.,  the  formation 
of  a  double  sodium  calcium  carbonate.  Analyses  by  J urisch( C hemt 
Indust.,  1880,  377)  would  lead  to  the  conclusion  that  this  loss  is  less 
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