Phosgene as a reagent in inorganic syntheses

Phosgene has been employed in the modification of the surfaces of cellulose-acetate membranes used for water desalination and waste water treatment [1450]. Similarly, phosgene has been used to surface-modify porous diaphragms for electrolytic cells [324]. Aluminium and aluminium-based alloys can be etched at a high rate when COClj is used in a mixed gas plasma [1004], as can semiconductors (see Section 9.12). 

In the manufacture of SOClj from phosgene [ICI82], sulfur dioxide and phosgene are combined over a charcoal catalyst at about 170 C (see Section 9.4.6) [ICI10,ICI32]. This process at one time formed the basis for manufacture of thionyl chloride (SOClj) in ICI. 

The reaction of phosgene with cadmium sulfide is said to be a good method for the preparation of COS (see Section 9.5.7) [885], used in the manufacture of organic thio compounds, whilst reaction of COCl, with iron(III) phosphate at 300-350 C has been proposed as a synthetic method for POCI3 (see Section 9.4.5) [885]. 

Phosgene can be used as the starting material for the preparation of other potentially useful carbonyl halides and carbonyl pseudohalides. Reaction of phosgene with fluorspar, for example, gives COCIF (see Section 9.1.1 and Chapter 16). With aluminium(III) bromide, COBrj is formed (Section 9.1.2.6). Reaction of COClj with HF gives COFj (see Section 9.10.4 and Chapter 13), reaction with silver cyanide gives carbonyl dicyanide, CO(CN)j (Section 9.1.7), whereas reaction with a mixture of sodium fluoride and HCN gives the mixed carbonyl halide pseudohalide, COFCN (Section 9.1.7 and Chapter 13). The chemistry of these 

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