This paper focuses on the finding best operational conditions using response surface methodology (RSM) for Rhodamine123 (R123) and Disulfine blue (DSB) dyes removal by ultrasound assisted adsorption onto Au-FeO nanoparticles loaded on activated carbon (Au-FeO NPs-AC). The influences of variables such as initial R123 (X) and DSB concentration (X), pH (X), adsorbent mass (X) and sonication time (X) on their removal were investigated by small central composite design (CCD) under response surface methodology. The significant variables and the possible interactions among variables were investigated and estimated accordingly. The best conditions were set as: 4min, 4.0, 0.025g, 13.5 and 26.5mgL for sonication time, pH, adsorbent weight, initial R123 and DSB concentration, respectively. At above conditions, the adsorption equilibrium and kinetic follow the Langmuir isotherm and pseudo-second-order kinetic model, respectively. The maximum monolayer capacity (Q) of 71.46 and 76.38mgg for R123 and DSB show sufficiency of model for well presentation of experimental data.

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Present study is devoted on the development of the effective methodology for removal ultrasonic to simultaneous removal of Bismarck Brown (BB) and Thymol Blue (TB) onto Au-Fe3O4 nanoparticles loaded on activated carbon (Au-Fe3O4-NPs-AC) in aqueous solution. The Au-Fe3O4-NPs-AC were synthesized and characterization by different techniques such as XRD, FE-SEM and FT-IR. The process efficiency was confirmed through examination of variables like initial BB and TB concentration (X1, X2, respectively), pH (X3), adsorbent mass (X4) and sonication time (X5). The optimum operating parameters (OOP) were evaluated by Response Surface Methodology (RSM) based on central composite design (CCD) for prediction and simulation of removal of BB and TB dye, while analysis of variances (ANOVA) give the estimate of significance of experimental variables. The experimental equilibrium data were fitted to the conventional isotherm models and accordingly Langmuir isotherm has good applicability for the explanation of experimental data with maximum monolayer capacity (Qmax) of 80 and 76.38 mg g-1 in binary system for BB and TB, respectively. Kinetic evaluation of experimental data showed that the BB and TB adsorption processes followed well pseudo-second-order and intraparticle diffusion models. The results of this study will be useful for further development of magnetic nanostructures for environmental applications.

The focus of this research is on the rapid ultrasound-assisted removal of Bismarck Brown (BB) and Thymol Blue(TB) dyes from aqueous solutions using Mn-Fe 2 O 4 nanoparticles loaded on activated carbon (Mn-Fe 2 O 4 -NPs-AC) as a low cost and environmental friendly adsorbent. The adsorbent was characterized by SEM, FTIR and XRD. The effect of variables such as initial concentration of BB, initial concentration of TB, pH of the solution, adsorbent dosage and sonication time on the removal percentages of BB and TB dyes were simultaneously investigated by central composite design(CCD) under response surface methodology(RSM). It was shown that the adsorption of BB and TB follows the pseudo-second-order rate equation, while the Langmuir model explains equilibrium data. Isotherms had also been used to obtain the thermodynamic parameters such as free energy (ÄG 0 ), enthalpy (ÄH 0 ) and entropy (ÄS 0 ) of adsorption. The negative value of ÄG 0 indicates the feasibility and spontaneity of the adsorption process. The positive ÄH 0 suggests the endothermal nature of the adsorption. The positive values of ÄS 0 reflects the affinity of Mn-Fe 2 O 4 -NPs-AC towards BB and TB dyes. A small amount of the adsorbent was able to remove more than 99.0% of both dyes rapidly with high adsorption capacity in binary-component system( 70.3 mg/g for BB, and 48.48 mg/g for TB).

A lev atomik absorpsiyon spektrometrisine dayanan etkin bir flotasyon yöntemiyle ayrım ve ön deriştirme adımları toplayıcı olarak ligand 3-((1H-indol-3-il) (4-Siyano fenil) metil) lH-indol (ICPMI) ile çeşitli gerçek örneklerde Cd 2+ iyonlarının tayini incelenmiştir. pH, ICPMI miktarı, numune matrisi, elüsyon maddesinin türü ve miktarı, yüzey aktif maddenin türü ve miktarı, iyonik kuvvet, hava akış oranı, yani ekstraksiyon sisteminin verimliliğini etkileyen değişkenler değerlendirildi. Kadmiyum iyonunun 0.012 mM ligandı, %0.025 (w/v) sodyum dodesil sülfat (SDS) ve pH 9.0±0.1 varlığında eşzamanlı olarak matristen ayrıldığı kesin olarak belirlendi. Bu iyonlar, metanolde 1M HNO 3 'ün 0.5 mL si ile nicel olarak, Cd 2+ için 0.02-2.2 µgmL-1 arasında ve Cd 2+ için saptama limiti 1.9 µgmL-1 olan doğrusal aralıklarla ayrılabilir. Yöntem, radyoloji atık suyu, amalgam, doğal su ve kan numuneleri örneklerinde az miktarda kadmiyum iyonu tayini için başarıyla uygulanmıştır. Anahtar Kelimeler İz, iyon flotasyonu, sodyum dodesilsülfat, alev atomik absorpsiyon spektrometresi.