Manufacture of high active detergent particles

Abstract

A process for manufacturing detergent particles comprising the steps of: a) forming a liquid surfactant blend comprising a major amount of surfactant and a minor amount of water, the surfactant part consisting of at least 51 wt % linear alkylbenzene sulfonate and at least one co-surfactant, the surfactant blend consisting of at most 20 wt % nonionic surfactant; b) drying the liquid surfactant blend of step (a) in an evaporator or drier to a moisture content of at most 2 wt % and cooling the output from the evaporator or dryer; c) feeding the cooled material, which output comprises at least 93 wt % surfactant blend with a major part of LAS, to an extruder, optionally along with less than 10 wt % of other materials such as perfume, fluorescer, and extruding the surfactant blend to form an extrudate while periodically cutting the extrudate to form hard detergent particles with a diameter across the extruder of greater than 2 mm and a thickness along the axis of the extruder of greater than 0.2 mm, provided that the diameter is greater than the thickness; d) optionally, coating the extruded hard detergent particles with up to 30 wt % coating material selected from powdered inorganic material and mixtures of such material and nonionic material with a melting point in the range 40 to 90° C.