Tetraethyl Lead Reaction Mass: Lead-Sodium Alloy Activated with Aluminium Chloride, Treated with Ethyl Chloride at 35-90 °C (Calcott, du Pont, US 1,962,173)

Tetraethyl lead is made by letting ethyl chloride attack a lead-sodium alloy under pressure. Du Pont found that a trace of aluminium chloride melted into the alloy makes it react better. Result: a reaction mass holding the tetraethyl lead, to be steam-distilled out (next blueprint). Variable: the alloy with or without aluminium chloride. Without it, the usual practice at 35-100 °C gave about 80 % of the theoretical yield; with it the patent says the yield is higher, without a figure. Source: Calcott, Parmelee & Meschter, US 1,962,173 (1934). Not given: pressure, amount of ethyl chloride. Danger: tetraethyl lead is a deadly poison that goes through skin; sodium burns in contact with water. Picture drawn by Youblob.