Marine pollution has been considered in increasing problems depending on the increment in sea transportation day by day. Therefore, the large volume of bilge water which contains petroleum, oil and hydrocarbons in high concentrations is generated from all types of ships. In this study, treatment of bilge water by electrocoagulation/electroflotation and nanofiltration integrated process is investigated as a function of voltage, time, and initial pH with aluminum electrode as both anode and cathode. Moreover, commercial NF270 flat-sheet membrane was also used for further purification. Box-Behnken design combined with response surface modeling (RSM) was used to study the response pattern and determined the optimum conditions for maximum chemical oxygen demand (COD) removal and minimum metal ion contents of bilge water. Three independent variables, namely voltage (5–15 V), initial pH (4.5–8.0) and time (30–90 min) were transformed to coded values. The COD removal percent, UV absorbance at 254 nm, pH value (after treatment), the concentration of metal ions (Ti, As, Cu, Cr, Zn, Sr, Mo) was obtained as responses. Analysis of variance results showed that all the models were significant except of Zn (P > 0.05), because of the calculated F values for these models were less than the critical F value for the considered probability (P = 0.05). The obtained R² and R_adj² values signified the correlation between the experimental data and predicted responses showed that except for model of Zn concentration after treatment, the high R² values showed the goodness of the fit model. While the increase in the applied voltage showed negative effects, the increases in time and pH showed a positive effect on COD removal efficiency, also the most effective linear term was found as time. A positive sign of the interactive coefficients of the voltage-time and pH-time systems indicated synergistic effect on COD removal efficiency, when interaction between voltage and pH showed an antagonistic effect.

This study investigates the development of sustainable polymer composites for structural strengthening by incorporating waste glass fibers and natural fibers (flax and hemp) into an epoxy matrix, in response to the growing environmental concerns. Mechanical, thermal, and durability-related properties were evaluated through tensile testing, dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), water absorption, and water immersion aging tests. Results showed that incorporating waste glass fibers enhanced the tensile strength and thermal decomposition temperature by 88% and 5.4%, respectively, compared to composites reinforced with solely natural fibers. Water absorption tests indicated that waste glass fiber-reinforced hybrid composites exhibited lower water uptake than flax and hemp fiber-reinforced composites. After water immersion, the tensile strength loss was recorded as 22, 25, and 8.5% for the composites reinforced with hemp, flax, and waste glass fiber, respectively. The findings confirm that incorporating waste glass fibers into natural fiber composites effectively mitigates moisture sensitivity and improves mechanical performance. Hybridizing flax and hemp fibers with waste glass fibers provides a practical and sustainable approach to enhancing composite performance, making them a viable alternative for strengthening reinforced concrete structures requiring long-term resistance. The recycled waste glass fibers employed in this study offered comparable mechanical performance while drastically lowering raw material consumption and environmental impact, in contrast to virgin glass fibers frequently used in earlier investigations. This demonstrates how recycling-oriented composite design can provide both sustainability and performance benefits.

This study was performed to synthesize graphene oxide (GO) and functionalized GO with photoactive semiconductor catalyst (TiO₂ and ZnO) blended composite polyethersulfone (PES) membrane. The performance of antifouling and self-cleaning properties of composite membranes were also investigated. The GO was prepared from natural graphite powder by oxidation method at low temperature. TiO₂ and ZnO nanopowders were synthesized by anhydrous sol-gel method. The surface of TiO₂ and ZnO nanopowders were modified by a surfactant (myristic acid) to obtain a homogeneously dispersed mixture in a solvent, and then GO was functionalized by loading of these metal oxides nanopowders. The PES membranes blended with GO and functionalized GO into the casting solution were prepared via phase inversion method and tested of antifouling as well as self-cleaning properties. The composite membranes were synthesized 14%wt. of PES polymer with three different concentrations of 0.5, 1.0, and 2.0%wt. GO, GO-TiO₂, and GO-ZnO. The functionalization of membranes improved hydrophilicity property of membranes as compared to neat PES membrane. However, the lowest flux was obtained by functionalized membranes with GO-TiO₂. The results showed that functionalized membranes demonstrated better self-cleaning property than neat PES membrane. Moreover, the flux recovery rate of functionalized membranes in those five cycles were higher than neat membrane.

Bu çalışmada, üç fazlı sistemle üretilen zeytin karasuyunun taşınabilir membran arıtma sisteminde arıtılması sonucu oluşan karasu membran filtre çamuruna (KMFÇ) uygulanan asidik (H3PO4, HNO3), bazik (NaOH), geri soğutucu altında termal ve hibrit termokimyasal önişlemlerin biyogaz üretim verimine etkisi araştırılmıştır. Termal önişlemler, 100 °C’de 1, 2 ve 3 saat süreyle gerçekleştirilirken; kimyasal önişlemler, KMFÇ’deki toplam katı madde kütlesinin %10’u oranında asidik ve bazik kimyasallar eklenerek uygulanmıştır. Önişlem uygulanan numunelere anaerobik fermentasyon yapılmış ve en yüksek hacimsel biyogaz ile metan üretim veriminin yalnızca HNO3 ile uygulanan önişlemde elde edildiği belirlenmiştir. 30 günlük ölçümler sonucunda 217,46 mL biyogaz ve 173,85 mL metan üretilmiştir. Biyogaz ve metan üretim verimleri sırasıyla 1,023 mL g⁻¹ TKM⁻¹ gün⁻¹ ve 0,818 mL g⁻¹ TKM⁻¹ gün⁻¹ olarak hesaplanmıştır. Elde edilen bulgular, HNO3 önişleminin KMFÇ’den biyogaz üretimini artırmada etkili bir yöntem olduğunu ve ileriki çalışmalara rehberlik edebileceğini göstermiştir.