Carbonaceous materials have great potential as catalyst supports since a high metal loading and dispersion can be achieved. Also, it is well known that the role of the support is not simply that of a carrier; the interaction between the active phase and the support can also affect the catalytic activity. The aim of this work was to develop catalysts on the basis of carbonaceous adsorbents by their impregnation with metals (Cr, Ni, Mn, Fe, Cu) for catalytic oxidation of nitrite and sulphide ions in water. Impregnation with metal ions and oxides was performed by different methods, and the catalytic properties of carbonaceous adsorbents depend on the nature and state of the metal (ions and oxides) bound on the surface, as well as on the support surface nature. The catalysts general properties were determined by standard methods (BET surface, SEM-EDX, XRD etc.), and the catalytic activity was evaluated by chemiluminescence in luminol/H2O2 system and by ABTS cation-radical method. By applying the chemiluminescence method (luminol/H2O2 system) the dualistic behaviour of activated carbons was revealed. According to the activated carbon structure characteristics (well-activated/graphitized structure, functional groups, π electrons, quinone hydroquinone couple, etc.) under different conditions activated carbon has a dualistic behaviour: on the one hand, it captures free radicals from different systems, and under other special conditions the activated carbon itself can form free radicals. Activated carbon, by means of the redox couple (quinone/hydroquinone) on the surface, in the luminol/hydrogen peroxide system contributes to the formation of free radicals that react with hydrogen peroxide, thus generating hydroxyl radicals OH• analogous to the Fenton reaction. Following the oxidation reaction of luminol with dissolved oxygen, the superoxide radical is produced: CA/CA(Cu) + H2O2 → CA CA(Cu) + HO● + HO- (1) CA/CA(Cu) + O2●- → CA CA(Cu) + O2 (2) The formed OH• radicals are quite reactive and, following the reaction with luminol, form an emission of chemiluminescence. Comparative analysis of the developed catalysts ability to remove/oxidize sulphur ions highlight samples modified with copper, nickel and manganese ions; the relative capacity (RC, %) decreases in the series CAT36Ni≈CAT36Mn˃CAT36Cu˃CAT36Cr˃CAT36Fe. In the process of sulphide ions removing from water in the presence of samples modified with nickel and manganese ions, colloidal sulphur is formed in considerable quantities. The results reveal that there is a dependence between the amount of metal immobilized on the surface of activated carbon and the amount of colloidal sulphur formed. The testing of catalysts (on the activated carbon as support) for removal (adsorption/oxidation) of nitrite ions from water highlights the samples modified with copper oxides from the E series and the samples modified with manganese from the C series. Meanwhile, the removal capacity of nitrite ions from water in presence of catalysts modified with copper oxides (E-Cu-Na2CO3, C-1-Cu-Na2CO3) reaches ~90% and is in agreement with the redox activity of the catalysts evaluated via the chemiluminescence method.