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In this work, activated carbon engrafted with Ag nanoparticles (Ag-NPs-AC) was prepared and applied for ultrasonic assisted simultaneous removal of aluminum (Al 3+ ) ions and Alizarin red S (ARS) dye from aqueous medium. The physicochemical properties of Ag-NPs-AC were determined by different techniques such as SEM and FTIR. Effects of various operating parameters on the extent of adsorption were investigated. The optimum of condition was determined in order to achieve maximum removal percentage from the binary mixture. It was observed that the maximum performance for both the species was achieved at pH of 6. The influence of different variables such as concentration of initial Al 3+ (mg L -1 ) ions, ARS (mg L -1 ), adsorbent mass (mg) and sonication time (s) were studied using central composite design (CCD) combined with desirability function approach (DFA) and genetic algorithm (GA). The isotherm models for the adsorption process were evaluated and the equilibrium data accurately described by the Langmuir model with maximum monolayer adsorption capacity for Al 3+ ions and ARS of 222.2 and 232.6 mg g -1 , respectively.

Chromium doped zinc oxide nanoparticles (ZnO: Cr-NPs) was synthesized by ultrasonically assisted hydrothermal method and characterized by FE-SEM, XRD and TEM analysis. Subsequently, this composite ultrasonically assisted was deposited on activated carbon (ZnO: Cr-NPs-AC) and used for simultaneous ultrasound-assisted removal of three toxic organic dye namely of malachite green (MG), eosin yellow (EY) and Auramine O (AO). Dyes spectra overlap in mixture (major problem for simultaneous investigation) of this systems was extensively resolved by derivative spectrophotometric method. The magnitude of variables like initial dyes concentration, adsorbent mass and sonication time influence on dyes removal was optimized using small central composite design (CCD) combined with desirability function (DF) approach, while pH was studied by one-a-time approach. The maximized removal percentages at desirability of 0.9740 was set as follow: pH 6.0, 0.019g ZnO: Cr-NPs-AC, 3.9min sonication at 4.5, 4.8 and 4.7mgL(-1) of MG, EY and AO, respectively. Above optimized points lead to achievement of removal percentage of 98.36%, 97.24%, and 99.26% correspond to MG, EY and AO, respectively. ANOVA for each dyes based p-value less than (<0.0001) suggest highly efficiency of CCD model for prediction of data concern to simultaneous removal of these dyes within 95% confidence interval, while their F-value for MG, EY and AO is 935, 800.2, and 551.3, respectively, that confirm low participation of this them in signal. The value of multiple correlation coefficient R(2), adjusted and predicted R(2) for simultaneous removal of MG is 0.9982, 0.9972 and 0.9940, EY is 0.9979, 0.9967 and 0.9930 and for AO is 0.9970, 0.9952 and 0.9939. The adsorption rate well fitted by pseudo second-order and Langmuir model via high, economic and profitable adsorption capacity of 214.0, 189.7 and 211.6mgg(-1) for MG, EY and AO, respectively.

A new Cr(iii) ion-imprinted polymer (Cr(iii)-IIP), prepared by functionalizing an SBA-15 support with dithizone (DZ) indicator, is promising and highly efficient for the separation and preconcentration of Cr(iii) ions from aqueous media.

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In this paper, two green electrochemical strategies for the synthesis of new Nphenylquinoneimine derivatives are reported. In the first strategy, the electrophilic activity of electrochemically generated quinone−diimine derivatives was used in reaction with phenol as a model nucleophile. In the second strategy, the electrochemically formed 4-tert-butyl-obenzoquinone was used as a model Michael acceptor in the reaction with 4morpholinoaniline, N-(4-aminophenyl) acetamide, and fast violet B. The reaction mechanism in both strategies is electron transfer−chemical reaction−electron transfer/ disproportionation (ECE/DISP). This study provided some new N-phenylquinoneimine derivatives in good yields by a one-pot reaction under ambient conditions without toxic reagents.

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Simultaneous ultrasonic-assisted adsorption of malachite green (MG) and safranin O (SO) onto ZnO nanorodloaded activated carbon (ZnO-NR-AC) as green and safe nanostructured adsorbent was studied. The adsorbent was characterized by SEM, FT-IR and XRD. The dependence of adsorption efficiency on various parameters such as pH, sonication time, adsorbent mass, initial MG concentration and initial SO concentration was investigated by central composite design (CCD) under response surface methodology (RSM). A predictive model was successfully constructed for the suitable description of real behavior of adsorption state. Optimum conditions at which the maximum removal of the MG (99 %) and SO (95 %) are achieved in short time were obtained. The adsorption kinetics and equilibrium isotherm were shown to be well described by the pseudosecond-order kinetic and Langmuir model, respectively. The reasonably high values of 59.17 and 55.25 mg g −1for the adsorption capacity of Zn-NR-AC were obtained for the adsorption of MG and SO, respectively.