Progress of various industries from the past decade led to a drastic increase in industrial effluent discharge, causing dramatically environmental pollution as well as serious life-threatening problems for environment in several regions. Colored wastewaters treatment by adsorption using alternative sorbents is a demanding domain. The efficiency of various sorbents underdifferent process parameters and their comparative adsorption capacity towards dyes adsorption is presented. In this paper adsorbents of different origin: (i) mineral adsorbents-diatomite (D1) and modified diatomite with sulphuric acid (D2); (ii) carbonaceous adsorbents modified with manganese compounds and treated at 250 ºC (P1) and 450 ºC (P2) were investigated for the removal of dyes from aqueous solutions. Three industrial dyes were selected as adsorbate: Methylene Blue (C.I. 52015, MB), Basic Red 2 (C.I. 50240, RB2), and Nylosan Blue (C.I. 62058, NB). The parameters such as adsorbent nature, and solution pH, were studied. The advantages and disadvantages of the various sorbent materials are discussed and their effectiveness is compared.Acknowledgments This work was partially supported by Program no 2, Project no. 2.4 from the Institute of Chemistry Timisoara of Romanian Academy, and by an inter-academic exchanges between Romania and Moldova.