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Aluminum is quite often plated to combine the advantages of the light metal with modified surface properties. In this study, copper strike electrodeposits obtained from cyanide and pyrophosphate strike baths were compared in terms of microstructure, and copper pyrophosphate strike was found to yield smoother deposits. Furthermore, about 50 µm thick copper depositions on the strike plated aluminum surface, were prepared from acid copper sulfate and copper pyrophosphate electrolytes to compare structural properties of the deposits. Comparison and characterization of copper electrodeposits from copper sulfate and pyrophosphate electrolytes were performed by potentiometry, SEM, roughness, and XRD analyses. Smoother and finer grained copper deposits were obtained from pyrophosphate electrolyte especially at low current densities.

Although anaerobic digestion is a well-established technology, the treatment and disposal of the digestate still presents a challenge due to lack of viable methods for processing. The residual organic matter in digestates also creates a significant residual biogas potential. This fact indicates that the digestates need further processing not only to reduce their organic content for disposal, but also to capture the biogas associated with this residual organic content. This study investigated anaerobic treatment and residual biogas potential of digestates obtained from five full-scale farm-based digesters. The results indicated that it was possible to reduce the total chemical oxygen demand (COD t ) of the digestates with an efficiency of 21%-84%. The corresponding biogas yields of digestates ranged between 0.078 and 0.326 L biogas /g VS added . This level of biogas production is comparable to the biogas production potential of several commonly used raw substrates. • Practitioner points• Significant CODt reduction and biogas capture can be attained by AD of digestates. • The digestates subjected to anaerobic treatment yielded up to 82% CODt removal. • Residual biogas yields of digestates ranged between 0.078-0.326 Lbiogas/g VSadded. • Biogas yields obtained were comparable to many raw feedstocks of biogas plants.

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Adsorption has traditionally been evaluated as an economical and easily applicable process for treating certain wastewaters, such as ones including dyes and heavy metals. Even though adsorbent materials specifically produced for the purpose of wastewater treatment commercially exist, the production cost may create an economic burden on wastewater treatment processes. Agricultural wastes can be valorized as adsorbents in adsorption processes. The adsorption capacity of these wastes can be improved via pre-treatment methods such as chemical application and microwave irradiation. This study investigated the potential applicability of hazelnut husk as an adsorbent for methylene blue (MB) dye. To this purpose, the husk was activated by sequential chemical or water and microwave applications.Structural analysis on the produced adsorbent was performed by Fourier transform infrared spectrophotometry (FTIR) and field emission scanning electron microscopy (FE-SEM).Isotherm (Langmuir, Freundlich, Temkin and Harkins-Jura isotherms) and kinetic (pseudofirst-order, pseudo-second-order, Elovich and intraparticle diffusion kinetic models) behaviours of adsorption were also evaluated. The results indicated that MB could be removed by 92-94% considering all adsorbents produced. Further isotherm and kinetic studies revealed that MB adsorption was both physically and chemically induced, and the reaction followed the pseudo-second-order kinetic model (R 2 >0.99).