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Ethanol dehydration was investigated over commercial H-FER, H-MFI, H-MOR, H-BEA, H-Y and H-USY zeolite samples, and alumina and silica alumina for comparison. The catalysts were characterized using FT-IR spectroscopy of the surface OH groups and of adsorbed CO and pyridine. UV–vis, Raman and TG-DTA were applied to characterize coke, formed more on H-MOR and H-BEA. H-zeolites are definitely more active than silica alumina and alumina on catalyst weight base. The H-MOR sample is the most active but the H-MFI samples with Si/Al2 ratios 280 and 50 show higher reaction rates per Al ion, H-FER and faujasites show highest ethylene yield (99.9% at 573 K). At lower temperature and higher space velocities, diethyl ether is formed with high yield (>70% at 453–473 K on H-BEA and H-MFI (50)). Overconversion of ethylene mainly to aromatics is observed on H-MFI (50). The different behaviour of protonic zeolites can predominantly be explained by confinement effects on the different zeolite cavities

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Second to autologous bone grafts are the calcium phosphate cements (CPCs) used as synthetic bone substitutes due to their chemical similarity to the mineral component of bone. Their ability to conform to complex bone defects and excellent osteoconductivity also render them excellent scaffolds for bone tissue engineering, although they do have their own limitations. Calcium phosphates can be divided into two main categories, namely apatite and brushite. Apatites exhibit low solubility, whereas, calcium phosphates that set to form brushite, are metastable, which degrade rapidly, but do subsequently form hydroxyapatite that retards the rate. In contrast dicalcium phosphate anhydrous (monetite) has a higher solubility than octacalcium phosphate and does not transform to an apatite; thus, it is able to continue to degrade with time. Herein, a new method was used via the addition of sodium chloride to btricalcium phosphate and monocalcium phosphate monohydrate to form micro-and macroporous monetite (DCPA). The X-ray diffraction and FTIR spectra confirmed the formation of monetite in the presence of both, 6.2 M NaCl solution or 60% of solid sodium chloride. The maximum compressive strength (s c ¼ 12.3 AE 1.8 MPa) and the Young's modulus (E ¼ 1.0 AE 0.1 GPa) of the monetite cements obtained were comparable to the upper limits of the values reported for cancellous bone and also higher than that reported by other routes used to form monetite. The porous cements analysed by microCT revealed an interconnected porosity with the preliminary in vitro biological evaluation indicating favourable osteoblast cell attachment and growth.