In this study, the effects of the combination of acid hydrolysis and Donnan dialysis on the high-quality struvite production from digested sewage sludge were examined. The Box-Behnken design was applied in the hydrolysis using oxalic acid for the optimization of the conditions that affect the nutrients and metal release from digested sludge. An optimal condition was obtained at oxalic acid 0.5 M, acid/sludge ratio (mL/g) 10/1, and reaction time 60 min. The separation of the metals from hydrolyzed sludge liquid was carried out with the Donnan dialysis using a Nafion 117 cation exchange membrane. At the end of the 4 hours of operating time, the recovery values for Zn, K, Na, Mg, Fe, and Al were obtained as 67.9%, 62.1%, 57.6%, 39.4%, 5.3%, and 2.5%, respectively. The produced struvite meets the legal limits for fertilizer use in terms of Cd, Cu, Ni, Pb, Zn, Hg, and Cr content specified by Turkish regulations. A high Ca/Mg molar ratio and the presence of K, Na, and Al affected the efficiency of struvite crystallization. The use of oxalic acid resulted in low Ca release, and the metal ions that affect struvite purity were eliminated using Donnan dialysis.

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A novel molecularly imprinted overoxidized polypyrrole electrode was produced for the determination of sulfasalazine (SSZ). The electrode was attained by electropolymerization of pyrrole onto a pencil graphite electrode by cyclic voltammetry. The SSZ was penetrated into the structure during the process. Differential pulse voltammetry was used to determine performance of imprinted (MIP) and non‐imprinted (NIP) electrodes. The linear range was attained in the range between 1.0 to 10.0 ppm of SSZ (R2=0.9993) with a detection limit of 0.265 ppm. The developed MIP electrode and analysis method are suitable for analysis of SSZ with reproducible response and precision in real samples.

This paper aims to review available information in the literature on the factors responsible on formation, species disinfection by-products (DBPs) and their health effects in swimming pool water. DBPs in swimming pools is significant for international literature and this review is the first study with the main focus of DBPs in swimming pool in national academic arena.Various disinfectants are applied in order to eliminate the pathogen microorganisms in drinking water distribution network and swimming pools. While chlorine based disinfectants are used commonly, also bromine based chemicals are preferential disinfectants. The sources of the organic matter precursors are; i) natural organic matter content of filling water and ii) organic loadings from swimmers. While disinfectants inactivate pathogens in swimming pools, mutagenic or carcinogenic DBPs are formed as a result of reactions between disinfectants and natural organic matter (NOM), bromide/iodide and human inputs. The formation of DBPs in swimming pool are higher than drinking water due to higher disinfectants residual and DBPs precursors. Trihalomethanes (THMs) and haloaceticacids (HAAs) are commonly observed as DBPs in swimming pools. THMs can be observed high concentration not only in swimming pool waters but also in indoor air ambition due to their volatile nature. Understanding of DBPs formation and control in swimming pools is important to minimize adverse health effects. It is much easier and cheaper to reduce DBPs before formation the pool with removal of precursors and use of proper disinfectants.

Hydrolysis of phosphorus and metals from anaerobically digested sewage sludge was tested using inorganic acids (H 2 SO 4 , HCl, and HNO 3) and organic acids (citric, oxalic, and acetic). Then, the optimize conditions for release of high phosphorus and low metals from digested sludge using H 2 SO 4 by Box-Behnken design was investigated. Optimum PO 4-P and metals (Ca, Mg, Na, K, Al, Fe and Zn) release was obtained at H 2 SO 4 0.3 M, acid/sludge ratio (mL/g) 10/1 and mixing time 90 min, respectively. Donnan dialysis having a Nafion 117 cation exchange membrane was employed the selective separation of released PO 4-P and metals in the hydrolysed sewage sludge liquid obtained at optimum conditions. HCl at different concentrations (0.1 and 1.0 M) were used in receiver side. High levels of metals (Ca 78.73%, Mg 38.11%, Na 49.43%, K 64.62%, Al 97.59% and Zn 34.73%) were passed the receiver side using 1 M HCl for 24 h. Hence, it was observed that selective separation of phosphate and metals from digested sludge using Donnan dialysis process was achieved for phosphorus recovery.