Hexadecyl Trimethyl Ammonium Bromide-Modified Montmorillonite as a Low-Cost Sorbent for the Removal of Methyl Red from Liquid-Medium

In this study, montmorillonite (MMT) modified with a cationic surfactant (Hexadecyl trimethyl ammonium bromide, (HDTMA)) was used for the removal of methyl red (MR) from aqueous solution. The effect of different parameters like surfactant loading rate, contact time, pH, adsorbent dosage and initial MR content was investigated on the sorption. The sorption capacity was increased by increasing the surfactants loading rate up to 120 cation exchange capacity (CEC) of the MMT. The optimum uptake capacity of the sorbent (84.28 mg/g) was achieved within 30 min at pH of 6. The experimental data of the sorption was well fitted by pseudo-second-order kinetic and Freundlich isotherm models. The results showed that the HDTMA-MMT can be applied as an effective and inexpensive sorbent for the removal of MR from aqueous solution

Air Quality and Health Risks Associated With Exposure to Particulate Matter: A Cross-Sectional Study in Khorramabad, Iran

Background: Among ambient air pollutants, particulate matter (PM) has the most undesired adverse effects on human health. Many studies have reported that there is a strong correlation between PM concentrations and hospital admissions due to chronic or acute respiratory and cardiovascular diseases. Objectives: The aims of this study were to evaluate the relationship between air quality and health endpoints of PM10 in Khorramabad, Iran. Materials and Methods: The PM10 sampling was carried out with a high-volume sampler at a flow rate of 1.1-1.4 m(3)/min from January through December 2014. Meteorological data was also collected and evaluated. The total mortality and morbidity rates were calculated using the AirQ2.2.3 software model. Results: The highest concentrations of PM10 were obtained in July, with the mean concentration of 136.48 mu g/m(3). Eastern and southeastern winds are the prevailing and semi-prevailing winds in Khorramabad. The worst air quality was also observed in July. The total mortality rate during the study was estimated to be 320 persons. Conclusions: In order to diminish the health impacts of particulate matter in Khorramabad, health training for the public, especially for persons with chronic lung and heart diseases, the elderly, and children, should be conducted by health systems to encourage them to reduce their activities during dusty days

Eriochrme black-T removal from aqueous environment by surfactant modified clay: equilibrium, kinetic, isotherm, and thermodynamic studies

In this study, the removal of Eriochrome black T (EBT) from aqueous solutions was evaluated by cationic surfactant of hexadecyl trimethyl ammonium bromide (HDTMA)-modified montmorillonite clay (MC). The effects of contact time, pH, adsorbent dosage, EBT concentration, solution ion strength, and temperature were investigated on the EBT removal. HDTMA-MC was also examined by Fourier transformed infrared (FTIR) spectroscopy and X-ray diffractometer (XRD). The results illustrated that the experimental data were well followed by the pseudo-second-order kinetic and Freundlich isotherm models. The results also showed HDTMA-MC can be used as an effective adsorbent for the removal of EBT from aqueous solution. © 2018 Informa UK Limited, trading as Taylor & Francis Grou

Eriochrme black-T removal from aqueous environment by surfactant modified clay: equilibrium, kinetic, isotherm, and thermodynamic studies

In this study, the removal of Eriochrome black T (EBT) from aqueous solutions was evaluated by cationic surfactant of hexadecyl trimethyl ammonium bromide (HDTMA)-modified montmorillonite clay (MC). The effects of contact time, pH, adsorbent dosage, EBT concentration, solution ion strength, and temperature were investigated on the EBT removal. HDTMA-MC was also examined by Fourier transformed infrared (FTIR) spectroscopy and X-ray diffractometer (XRD). The results illustrated that the experimental data were well followed by the pseudo-second-order kinetic and Freundlich isotherm models. The results also showed HDTMA-MC can be used as an effective adsorbent for the removal of EBT from aqueous solution. © 2018 Informa UK Limited, trading as Taylor & Francis Grou

H2SO4-modified Aloe vera leaf shells for the removal of P-chlorophenol and methylene blue from aqueous environment

In this study, the surface properties of activated carbon from Aloe vera leaf shells were modified by sulfuric acid Aloe vera-acid activated carbon (AV-AAC) and then used as a novel adsorbent to remove para-chlorophenol (p-CP) and methylene blue (MB) from aqueous solutions. The adsorbent was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis and Fourier transform infrared spectra (FTIR). The maximum monolayer adsorption capacities were found to be 137 and 192.3 mg/g for p-CP and MB, respectively. Due to low-cost and high adsorption capacity, AV-AAC can be considered as an effective adsorbent for wastewater treatment containing p-CP or MB. © 2018 Informa UK Limited, trading as Taylor & Francis Grou