PHOSPHATE adduct, namely, 2-hydroxy-3-chloropropylphosphate was reacted with starch in presence of sodium hydroxide catalyst according to the dry process to yield starch hydroxypropyl phosphate. The reaction was conducted under a variety of conditions and the extent of reaction expressed as DS (degree of substitution), was found to rely on catalyst concentration and phosphate adduct concentration as well as duration and temperature of the reaction. In this way starch molecules bearing different amounts of hydroxypropyl phosphate groups could be achieved. Evaluation of these starch hydroxypropyl phosphates as flocculant for ferric laurate and kaolin was performed under different conditions including dose, phosphorus content, pH of the flocculation and molar mass. The results obtained advocate the namely synthesized starch hydroxypropyl phosphates as a good candidate for flocculation vis-à-vis the well known poly(acrylamide-co-acrylic acid) which is used as industrial flocculant.