Cette étude présente les principaux résultats se rapportant d'une part à l'évolution des consommations en chlore par des composés organiques en solutions synthétiques de minéralisation variable. D'autre part, quelques essais sont consacrés aux possibilités de formation de sous- produits de la chloration tels les trihalométhanes.Les différences de réactivité entre les composés simples (phénol, résorcinol, aniline) et les substances humiques, déjà observées en eau distillée, ont pu également être mises en évidence lors de leur dilution dans des milieux minéralisés (eaux de sources ou de forages). L'influence de la minéralisation, appréhendée par le paramètre "conductivité" ou par des teneurs variables en éléments minéraux spécifiques, s'est concrétisée par des écarts souvent considérables entre les potentiels de consommation en chlore en eau distillée et ceux en eaux minéralisées.La présence d'ions bromures dans les eaux les plus minéralisées induit en particulier une formation plus importante des THM bromés. L'intervention d'ions chlorures et sulfates, en provoquant une diminution des potentiels de consommation en chlore, peut rendre plus complexe le schéma réactionnel du chlore avec les différentes entités réactives présentes dans une eau naturelle.L'application du procédé de chloration à des eaux de surface algériennes a permis de distinguer entre les eaux très minéralisées du sud algérien et celles moins minéralisées du nord du pays.Leur réactivité vis-à-vis du chlore s'est trouvée directement liée à leurs caractéristiques physico-chimiques.Les différences de réactivité relevées peuvent être attribuées d'une part à la variabilité de la proportion en matériel humique et d'autre part aux teneurs relatives en éléments minéraux promoteurs ou inhibiteurs de la réaction de chloration.The organic compounds studied during this work are simple aromatic structures (phenol, resorcinol, aniline), as well as macromolecular structures (humic substances). These compounds are representative of natural organic matter in surface waters. Various studies (De Laat et al., 1982; Norwood and Christman, 1987; Legube et al., 1990) showed that chlorination of these organic substances led to a strong chlorine consumption and the formation of volatile and non-volatile organohalogenated compounds. However, the majority of these experiments were conducted in aqueous media at very low ionic strength or in distilled water. The aim of the present study was to observe the reactivity of organic compounds in mineralised media. Indeed, Algerian waters are often very mineralised, excessively hard with high amounts of chloride and sulphate (Achour, 2001). In addition, humic substances can account for 60 to 90% of the total organic carbon (TOC) in most surface waters used to produce drinking water (Achour and Moussaoui, 1993).The first part of this study involved the investigation of the impact of the overall parameter "total mineralisation", which can be directly related to conductivity measurements in the dilution waters. In addition to distilled w...

Calcium treated bentonite clay (CTBC) was prepared by CaCl 2 impregnation of Algerian bentonite clay. The prepared adsorbent was characterized and successfully used to remove Cu (II) ions from aqueous solutions at different conditions (pH, stirring time and initial copper concentration). Results showed that the raw bentonite was changed completely into Ca-bentonite, which exhibits a high adsorption capacity (qt=19.98 mg g −1 ) at pH=5.0. It appeared that the sorption mechanisms are simultaneous and strongly depend on pH value. In the pH range from 3-10, the removal of copper occurs mainly by ion exchange, surface metal complexation and precipitation of Cu (OH) 2 . It was also found that the experimental data of kinetic adsorption are well fitted by the pseudo-first order model. Equilibrium data obeyed the Langmuir isotherm with maximum adsorption capacity of 55.48 mg g −1 .The mean adsorption energy predicted by Dubinin-Radushkevich model (E=1.55 Kj/mol) shows the physical nature of the adsorption interactions. Results of this study suggest the potential of the prepared CTBC which can be used easily for fast decontamination of wastewater containing toxic metal ions.

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a b s t r ac tIt is well known that the reactivity of chlorine with the humic substances results the formation of organohalogens in particular trihalomethanes suffering having chronic toxicity (mutagenic and/or carcinogen). These compounds, if they are formed no treatment can eliminated them. In this context, the aim of our work is to test the performance of powder activated carbon on removing the humic substances in the various mediums of mineralization. The adsorption testing is performed in batch by adopting different operating conditions. We thus evaluated various parameters relating to adsorption laws who will inform us about the retention capacity of the adsorbents with respect to humic substances of the water tested. The physicochemical characteristics of the water tested were also determined. The results have shown that the tested water is characterized by a more or less important mineralization and the quality varies from very good to poor. The adsorption tests showed that the removal of humic substances on carbon activated powder is more or less important, according to the mineralization of water. The yields obtained ranging 92.10%-100% with an equilibrium time vary from 30 to 240 min. According to all the results that we obtained, we also suggest that mineralization has notable influence on the adsorption process, either globally or through the mineral elements present. Similarly, the origin and nature of the humic material, the particle size and the distribution of pores adsorbents, as well as the physicochemical characteristics of the medium significantly affect the removal efficiency of humic substances. The effectiveness of these adsorbents and the increasing of adsorption capacity were clearly appeared through the exploitation of our results by the Freundlich and Langmuir isotherms.

The main objective of our work is to test the performance of powder activated carbon (PAC) and granular activated carbon (GAC) in the retention of humic substances in the presence of lead. The adsorption tests conducted in synthetic solutions of distilled water. The results showed that, the removal efficiency of humic substances varies with the agitation time was obtained maximum efficiency after 180 minutes for PAC and 300 for the GAC. However, on granular activated carbon (GAC) recorded an improvement in the removal of humic substances in the order of 1.60%. The reaction rate is the same for the activated carbon powder (PAC). By against, for the GAC the removal rate of humic substances in the presence of lead is slower. A comparison between our results with the absorption of humic substances without the presence of lead showed that the elimination of humic substances (10 mg/l) in the presence of lead (5mg/l) on powder activated carbon (1 g/L) is disturbed. The removal efficiencies decrease with the increase on the pH of medium in an interval ranging from 2 to 12.The variation of the mass of lead has recorded an inhibiting role in the adsorption of humic substances for both activated carbons.