Environmental Engineering / Çevre Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/4321
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Book Part The Role of Polyurethane Foam Indoors in the Fate of Flame Retardants and Other Semivolatile Organic Compounds(American Chemical Society, 2021) Genişoğlu, Mesut; Sofuoğlu, Sait Cemil; Sofuoğlu, AysunFlame retardant chemicals are added to polyurethane foams (PUFs) during production. These chemicals are released to the environment during the use of PUF containing furniture or building materials. In contrast, organic pollutants such as polychlorinated biphenyls, polycyclic aromatic hydrocarbons, synthetic musk compounds, and volatile organic compounds could be sorbed by PUF depending on the concentration gradient, ambient temperature, and the physicochemical properties. Most of these substances tend to accumulate by adhering to organic matter in dust, particles, and surfaces, as they do not degrade for long periods of time. Sorption-emission cycles of PUF-associated organic compounds prolong their presence in indoor environments, which could increase human exposure. Since these organic compounds might have carcinogenic or chronic-toxic health effects on living organisms, it is important to understand the role of PUF in exposure to these substances in indoor environments. This chapter reviews the literature on the relationship of organic substances with PUF in indoor environments.Article Citation - WoS: 3Citation - Scopus: 4Use of Nano Zero-Valent Iron Coated Coffee Grounds for Removal of Zn(ii) and Ni(ii) From Aqueous Solutions(Desalination Publications, 2019) Gören, Ayşegül Yağmur; Genişoğlu, Mesut; Ökten, Hatice EserThis research investigates the adsorption capacity of a novel composite material, namely nano zero-valent iron coated coffee grounds (nZVI-CG), for removal of zinc (Zn) and nickel (Ni). nZVI particles were synthesized and immobilized to the surface of waste coffee grounds (CG) using the ultrasonic-assisted liquid phase method. Characterization of synthesized nZVI-CG composite and bare CG showed that nZVI coating has increased the surface area significantly. Batch tests were conducted to examine the effects of pH, reaction time and initial metal concentrations on Zn2+ and Ni2+ removal. At an initial metal concentration of 10 mg-Ni/L and 10 mg-Zn/L, nZVI-CG removal rates for Zn2+ and Ni2+ were observed as 98.89% and 97.29%, respectively; while removal rates of bare CG have remained at 51% (Zn2+) and 48.1% (Ni2+). Moreover, acidic conditions were observed to deteriorate Ni2+ and Zn2+ adsorption since most functional groups of the metals were protonated. Increasing initial nickel and zinc concentrations decreased removal rates. While the model fittings improved with increasing pH, in the case of nZVI-CG, Langmuir isotherm gave the best fits for Ni2+ and Zn2+ at pH 5 and 7. Also, our experimental results followed the pseudo-second-order kinetic model, regardless of the used adsorbent. Consequently, our results showed that nZVI-CG composite material is a promising alternative adsorbent for pilot scale metal removal/recovery applications.
