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Hydrogen is a green, environmentally benign and sustainable energy source with no harmful combustion products to fulfil the increasing energy demand. Photocatalytic oxidation has various advantageous to produce hydrogen from different sources such as wastewater, alcohol solutions using different types of catalysts. Sucrose solution was chosen as a model solution to evolve hydrogen

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Hydrogen is a clean and green fuel and can be produced from renewable sources via photocatalysis. Solar-driven hybrid catalysts were synthesized and characterized (scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer−Emmett−Teller (BET), X-ray diffraction (XRD), photoluminescence (PL) spectroscopy, and UV−vis diffuse reflectance spectroscopy (DSR)), and the results implied that graphene-supported LaRuO 3 is a more promising photocatalyst to produce hydrogen and was used to produce hydrogen from sugar industry wastewater. To investigate the main and interaction effects of reaction parameters (pH, catalyst amount, and [H 2 O 2 ] 0 ) on the evolved hydrogen amount, the Box−Behnken experimental design model was used. The highest hydrogen evolution obtained was 6773 μmol/g cat from sugar industry wastewater at pH 3, 0.15 g/L GLRO, and 15 mM H 2 O 2 . Based on the Pareto chart for the evolved hydrogen amount using GLRO, among the main effects, the only effective parameter was the catalyst amount for the photocatalytic hydrogen evolution from sugar industry wastewater. In addition, the squares of pH and two-way interaction of pH and [H 2 O 2 ] 0 were also statistically efficient over the evolved hydrogen amount.

Hydrogen is a clean, environmentally friendly, storable, and sustainable green energy source as well as a potential fuel. It could be produced from various biomass, wastewater, or other sources by different processes. In this study, hydrogen was evolved from sucrose model solution and real sugar beet wastewater by photocatalytic oxidation using a perovskite catalyst under solar light irradiation. In this context, firstly, the graphene supported LaFeO3 (GLFO) was synthesized and then, a characterization study shows that GLFO is successfully synthesized. To optimize the reaction parameters (pH, catalyst loading, and initial hydrogen peroxide concentration), an experimental matrix was created using the Box Behnken model. Whereas the highest hydrogen evolution from sucrose model solution was observed as 3520 μmol/gcat, the highest hydrogen evolution from sugar beet wastewater was obtained as 7035 μmol/gcat. The highest TOC removal (99.73 %) from sugar beet wastewater was also achieved at the same reaction conditions.

Mühendislik bir ülkenin kalkınmasında ve gelişmesinde çok önemli rol oynayan disiplinler arası ortaklığın meydana getirdiği bir üst bilim dalıdır. Mühendislik, matematiksel ve doğal bilim dallarından, ders çalışma, deney yapma ve uygulama yolları ile kazanılmış bilgileri akıllıca kullanarak, doğanın kuvvetleri ve maddelerini insanoğlu yararına sunmak üzere ekonomik olan yöntemler geliştiren bir meslektir. Çünkü mühendislik yaklaşımı; işi sorun çözmek olan insan yaklaşımıdır. Mühendislik yaklaşımı içinde bulunan çalışanlar, görülmeyeni görerek, düşünülmeyeni bularak, optimum çözümleri hedefleyip durumdan maksimum faydayı çıkarmayı bilirler. Diğer taraftan mühendislik nedir, sorusu ile aklımıza çok geniş ve detaylı bir tanımlama gelse de genel olarak mühendislik, problemleri çözebilmek için gerekli olan bilim ve matematiğin uygulanmasıdır diyebiliriz. Mühendisler, bir şeylerin nasıl çalıştığını anlar ve bilimsel keşiflerin pratik hayatta kullanımı için yöntemler bulur. Yayınlanan bu kitap; çeşitli mühendislik dallarında hocalık yapan akademisyenlerin sunmuş olduğu gerek kendi özgün çalışmaları ve gerekse literatürden aktarılan derleme çalışmaların bir araya getirilmiş sunumlarından meydana getirilmiştir. Burada amaç konuyla ilgilenen mühendis ve akademisyenlerin önemli sayılacak mühendislik çalışmalarını bir arada bulmalarıdır. Dolayısıyla kitabın önemli bir boşluğu dolduracağı ve genç araştırmacılara faydalı olacağı kanaatindeyim. Bu bağlamda; kitaba bilimsel katkı sunan, kitabı baskıya hazırlayan kısacası emeği geçen herkese teşekkür ederiz. Yayımlanan bu kitabın gerek mühendislere ve gerekse genç akademisyenlere faydalı olmasını diler, tüm mühendis ve genç akademisyenlere başarılar dilerim.   Prof. Dr. Kamil KAYGUSUZ Karadeniz Teknik Üniversitesi Türkiye Bilimler Akademisi Asli Üyesi

The sugar industry is one of the most wastewater‐producing industries and it contains high content of organic and inorganic substances. Treating and reusing wastewater has significant importance because sugar industry needs to use a high volume of water. In this study, sugar industry wastewater was treated under subcritical conditions and the impacts of reaction temperature and duration over TOC removal percentage were investigated. Additionally, the impact of NaOH concentration over TOC removal percentage was examined. The highest TOC removal was obtained almost 95 % in the presence of 0.1 M of NaOH at 240 °C for 90 min of reaction duration. Treatment of sugar industry wastewater by subcritical water oxidation followed the second‐order reaction kinetic model and the activation energy was found as 11.41 kJ/mol. Furthermore, the intermediate products were identified via GC‐MS.

A novel hybrid adsorption-electrodialysis (AdED) system to remove environmentally harmful boron from geothermal brine was designed and effective operating parameters such as pH, voltage, and flow rate were studied. A cellulose-based adsorbent was synthesized from glycidyl methacrylate (GMA) grafted cellulose and modified with a boron selective n-methyl-d-glucamine (NMDG) group and characterized with SEM-EDX, FT-IR, and TGA analyses. Batch adsorption studies revealed that cellulose-based adsorbent showed a remarkable boron removal capacity (19.29 mg/g), a wide stable operating pH range (2–10), and an adsorption process that followed the Freundlich isotherm (R 2 = 0.95) and pseudo-second-order kinetics (R 2 = 0.99). In the hybrid AdED system, the optimum operating parameters for boron removal were found to be a pH of 10, a voltage of 10 V, a flow rate of 100 mL/min, and an adsorbent dosage of 4 g/L. The presence of the adsorbent in the hybrid system increased boron removal from real geothermal brine (containing 199 ppm boron) from 7.2% to 73.3%. The results indicate that the designed AdED system performs better than bare electrodialysis for boron removal from ion-rich real geothermal brine while utilizing environmentally friendly cellulose-based adsorbent.