preparation of phosphorylchlorideThe action of P
2O
5 upon CCl
4 was examined. While heating 1 mole P
2O
5 with 2 to 3 moles of CCl
4 at 200-210°C for 48h the P
2O
5 disappears and COCl
2 forms by the equation:
P2O5 + 2 CCl4 __> COCl2 + CO2 + 2 POCl3 80% of the theoretical amount of phosgene were obtained. A part of the CCl
4 always remains unchanged. Reducing the amount of CCl
4 while that of the P
2O
5 stays the same, less COCl
2 is formed until finally only traces are obtained. The reaction would then be expressed by:
2 P2O5 + 3 CCl4 __> 4 POCl3 + 3 CO2After the POCl
3 is distilled off, a thick colorless mass remains, a product of reaction between POCl
3 and excessive P
2O
5Chem.Ber. - 5.1872;30
J. Am. Chem. Soc.; Vol. 63; ( 1941 ) 1782 - 1789. P
2O
5 w/NaCl at ~250°C gives POCl
3 H.A. Curtis, R.L. Copson and A.J. Abrams, Chem. and Met. Eng., 44, No. 3, 140-142 - 1937 Article referenced in the one above
Patent BP356238
Example IA mixture of tricalcium phosphate and carbon in excess is dried and mixed with 5% of zinc chloride. This mixture is heated to 500-600°C while a stream of chlorine is conducted over it. The reaction takes place easily, phosphorous-chlorine compounds being formed, which distil over with the carbon monoxide also produced, while calcium chloride remains as residue.
POCl
3 procedures:
Patent US2829031
: H
3PO
4 is sprayed onto residue from sugar cane and chlorinated at 550°C ;
Patent US2712494
: granular charcoal (soaked with H
3PO
4) is chlorinated between 500 and 700°C
C. A.; 1954; 9028 : 75 to 80 % H
3PO
4 is concentrated and with addition of granular, powdered charcoal dried and treated with Cl
2 at 400 to 500°C
Patent US1688503
: Ca
3(PO
4)
2 + 8 SiO
2 + 10 NaCl
__> 2 PCl
5 + 3 CaSiO
3 + 5 Na
2SiO
3 ; 1100 - 1400°C
--
psyloxy--