Adsorption of Bisphenol-A by Eucalyptus bark/magnetite composite: Modeling the effect of some independent parameters by multiple linear regression

In the present study, Eucalyptus camaldulensis bark/magnetite composite was used for potential application as a low-cost adsorbent for the removal Bisphenol-A. The effects of various independent parameters, contact time, initial Bisphenol-A concentration, temperature, pH, and Eucalyptus camaldulensis bark/magnetite composite dosage on adsorption were investigated. It was found that the adsorption capacity of Eucalyptus camaldulensis bark/magnetite composite increases with the increasing of Bisphenol-A concentration, temperature, and decreasing dosage of Eucalyptus camaldulensis bark/magnetite composite. The adsorption capacity was found to be 290.6 mg/g with 0.1 g Eucalyptus camaldulensis bark/magnetite composite at pH 7 and 50?. The Freundlich isotherm model described the adsorption process better (R2= 0.998) than the Langmuir, Dubinin–Radushkevich, Jovanovic, and Vieth–Sladek isotherm models. According to multiple linear regression analysis, Eucalyptus camaldulensis bark/magnetite composite dosage is the most effective parameter on adsorption capacity at equilibrium and independent variables accounted for 79.4% of the total variability of equilibrium adsorption capacity of Eucalyptus camaldulensis bark/magnetite composite. © 2016, © The Author(s) 2016

Adsorption of reactive dye from aqueous solution and synthetic dye bath wastewater by Eucalyptus bark/magnetite composite

PubMedID: 27685968In the present study, Eucalyptus camaldulensis bark/magnetite composite (EBMC) was used for a potential application as a low-cost adsorbent for the removal of Reactive Black 5 (RB5). The adsorption experiments were performed with aqueous solution (RB5 + distilled water) and synthetic dye bath wastewater (SDBW) in order to investigate the potential application of EBMC in the textile industry. The effects of the various parameters, the initial dye concentration, the temperature, the pH, and the EBMC dosage on the adsorption were investigated. It was found that the adsorption capacity of EBMC increases by increasing the RB5 concentration and temperature and by decreasing the dosage of EBMC. 0.8 g EBMC was found to be sufficient for the removal of 250 mg/L RB5 from 150 mL SDBW with ~85% removal efficiency. The Koble-Corrigan isotherm model described the adsorption process more effectively (R2 = 0.997) than the Langmuir, Freundlich, the Dubinin- Radushkevich and the Jovanovic isotherm models. The Langmuir isotherm predicted a 370.7 mg/g maximum adsorption capacity. The thermodynamic analysis showed that the adsorption of RB5 onto the EBMC was an endothermic process. The multiple linear regression analysis was used in order to determine the cumulative effects of independent variables on the adsorption capacity. © IWA Publishing 2016

Adsorption of hexavalent chromium by eucalyptus camaldulensis bark/maghemite nano composite

In the present study, Eucalyptus camaldulensis bark/maghemite composite (ECMC) was used for potential application as a low-cost adsorbent for the removal of Cr(VI) from aqueous solution. The structural characterization, morphology and elemental analysis of ECMC were performed by Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray (EDX) and X-ray Diffraction (XRD). The effects of various independent parameters, contact time, initial Cr(VI) concentration, temperature, pH, and adsorption were investigated. It was found that the adsorption capacity of ECMC increases with increasing Cr(VI) concentration and temperature. The optimum pH was found to be 2 for the removal of Cr(VI) by ECMC. The adsorption capacity was found to be 70.1 mg/g with 0.1 g ECMC at pH 2 and 30 °C. Additionally, 10 and 50 mg/L Cr(VI) were removed from 100 mL aqueous solution by 0.1 g ECMC with 99 % and 93.46 % removal efficiencies, respectively. Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Jovanovic, Smith, Koble Korringen, Vieth-Sladek and Sips Isotherm Models were applied to the experimental data to understand the adsorption mechanism better. The Freundlich Isotherm Model described the adsorption process better (R2 = 0.991) among the other isotherms studied. © 2018 Walter de Gruyter GmbH, Berlin/Boston

Removal of phenol, threat to public health, from water by a low cost activated carbon [Halk sağliği için tehdit oluşturan fenolün sulardan düşük maliyetli bir aktif karbon ile giderimi]

In this study, a low cost activated carbon which based on Eucalyptus camaldulensis barks (ECAC) was used for the removal of phenol, threat to aquatic organisms and public health, from water. The effect of contact time, temperature, ECAC dosage and initial phenol concentration on adsorption process were investigated. It was found that pH, ECAC dosage and initial phenol concentration had a significant effect on adsorption process. The adsorption capacity was found to be 107.25 mg/g for 500 mg/L phenol at pH 5, 20 °C with 1 g ECAC dosage. The maximum adsorption capacity was predicted 136.5 mg/g by Langmuir isotherm. Freundlich isotherm described the adsorption process successfully by a 0.997 correlation coefficient

Fixed bed study for the adsorptive removal of Reactive textile dye with Eucalyptus bark/magnetite composite

In the present study, Eucalyptus camaldulensis barks/magnetite composite (EBMC) was used for potential application as a low cost adsorbent for the removal of a textile dye Reactive Blue 29 (RB29) from synthetic dye bath wastewater with fixed bed column adsorption systems. The effects of various parameters such as the pH, the column bed depth, and the temperature of the synthetic dye wastewater on the breakthrough time were investigated. It was found that the breakthrough time increased with the increasing pH, the column bed depth, and the temperature. The optimum pH and temperature for the effective removal of RB29 was found to be 9 and 40 °C, respectively. The breakthrough time for a 20 cm bed depth was found to be 550 minutes at pH 9 and 40 °C. The maximum adsorption capacity was calculated 850.21 mg/g from the Thomas isotherm model under certain operation conditions. The BDST model described (R2=0.997) the fix bed adsorption process perfectly. © by PSP

Impact of tumor stage, operative down-staging, tumor grade and radioresponsitivity of the tumor on survival in supratentorial astrocytomas

PubMedID: 10089070This retrospective study analyzed specifically the predicting factors for radioresponse and survival in 74 supratentorial astrocytoma patients. As a result of this study, cytoreduction in terms of ODs to T1 or T0 stage level or pre-RT T1 tumor stage along with radioresponse has a positive impact on long-term survival. It seems that radical radiotherapy should be the choice of treatment for the patients who had pre-RT T0 and T1 disease who were found more likely to respond to radiotherapy. This has not been reported previously and needs to be confirmed in larger trials