In this work, glycerol oligomerization to produce dust suppressants in the presence of acids (H2SO4 or H2SO4) and basic (NaOH) catalysts was investigated. The obtained results showed that kind of catalyst and its concentration are critical to obtain good yield for olygomers, as verified by Thermogravimetric Analysis. Under optimized condition it was possible to obtain reaction solutions with viscosity greater than 160 times that of glycerol and good suppressive action of dust, with only molar rate of 3% H2SO4, 140 degrees C/1 h. Since using crude glycerol derived from biodiesel production and 380 degrees C, was obtained hexa and heptaglycerol, in 3 h (verified by ESI-MS). Tests for dust suppression performance with the product derived from crude glycerol showed higher efficiency of material, when compared to products of oligomerization of glycerol and a commercial product. (C) 2011 Elsevier B.V. All rights reserved.