Browsing by Publisher "Desalination Publications"

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    Removal of arsenic(III) ions from aqueous solutions by modified hazelnut shell
    (Desalination Publications, 2017) Sert S.; Çelik A.; Tirtom V.N.
    In this study, modified hazelnut shells (HS) were used to remove As(III) ions from aqueous solu­tions. For this purpose, FeCl3 and FeCl3 + NaOH were used as modifying agents. Several important parameters influencing the adsorption of As(III) ions such as contact time, pH, temperature and initial metal concentration were investigated following batch experiments. From the results, it is indicated that temperature 20°C and solution pH = 9.0 are the optimum conditions for adsorption. Maximum adsorption experimental capacities of HS that was treated with FeCl3 and FeCl3 + NaOH were 4.37 and 11.84 mg g-1 for arsenic, respectively. The adsorption data at optimum conditions were analyzed by Freundlich, Langmuir, Dubinin-Radushkevich and Temkin isotherm models, and it was found that Freundlich isotherm model gives better fit. Thermodynamic parameters such as enthalpy change (ΔH°), entropy change (ΔS°) and free energy change (ΔG°) were also calculated. These results were indicated that the adsorption of arsenic on HS is exothermic and proceeds spontaneously. Additionally, it can be said that these adsorptions are physical because the Gibbs free energy change (ΔG°) for both adsorbents were found lower than 20 kJ mol-1. © 2017 Desalination Publications. All rights reserved.
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    Vulnerability of sewer network – graph theoretic approach
    (Desalination Publications, 2020) Ganesan B.; Raman S.; Ramalingam S.; Turan M.E.; Bacak-Turan G.
    One of the most important structures in urban areas is an efficient sewer system to protect humans and the environment from the detrimental effects of wastewater. Such sewer systems often consist of pipes, manholes, pumping stations, and other complementary units. Strict monitoring of the sewer system is highly essential as any leakage can cause undesirable effects on health and safety. The layout is modeled as a graph which contains all sewer links and satisfies all the restrictions of a sanitary sewer system. In this work, we apply centrality measures on the sewer network system and water distribution system and also analyze the vulnerability of these systems. © 2020 Desalination Publications. All rights reserved.