A process for the preparation of a sulphur cement product is disclosed. Sulphur is mixed with a coupling agent and with a particulate inorganic material at a temperature at which sulphur is molten to obtain a molten sulphur cement product, which is solidified. The coupling agent is supplied as a solid composition comprising the coupling agent and at least 10 wt %, based upon the weight of the solid composition, of carrier material selected from one or more of wax, inorganic filler and polymer. The coupling agent is chosen from the group of organosilanes and organotitanates.