Facile synthesis of nanosized sodium magnesium hydride, NaMgH₃

The ternary magnesium hydride NaMgH3 has been synthesised via reactive milling techniques. The method employed neither a reactive H2 atmosphere nor high pressure sintering or other post-treatment processes. The formation of the ternary hydride was studied as a function of milling time and ball:powder ratio. High purity NaMgH3 powder (orthorhombic space group Pnma, a=5.437(2) Å, b=7.705(5) Å, c=5.477(2) Å; Z=4) was prepared in 5 h at high ball:powder ratios and characterised by powder X-ray diffraction (PXD), Raman spectroscopy and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX). The products formed sub-micron scale (typically 200–400 nm in size) crystallites that were approximately isotropic in shape. The dehydrogenation behaviour of the ternary hydride was investigated by temperature programmed desorption (TPD). The nanostructured hydride releases hydrogen in two steps with an onset temperature for the first step of 513 K

Adsorption of Algerian Asphaltenes onto Synthesized Maghemite Iron Oxide Nanoparticles

In this study, the adsorption of Algerian asphaltene sample extracted from Hassi Messaoud oil field is conducted for the first time. The adsorption process was performed using novel synthesized iron oxide nanoparticles (γ-Fe2O3). γ-Fe2O3 Nanoparticles were in-house synthesized and characterized by an array of techniques using, Brunauer-Emmett-Teller (BET), high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). The results showed that the synthesized nanoparticles have an average crystalline domain size around 10 nm and a specific surface area of 120 m2/g. The adsorption process of the Algerian asphaltenes took place in a batch mode by dissolving the asphaltenes in toluene at 25°C. Different initial concentrations of asphaltene solutions were used in this study, namely 100, 500, and 1000 ppm. During this adsorption, both isotherm and kinetic studies were investigated. The results showed that the synthesized iron oxide nanoparticles are promising nano-adsorbents that have a high affinity to remove the asphaltenes and the equilibrium was recorded after 15 min. The Solid-Liquid-Equilibrium (SLE) model was used to correlate the adsorption experimental data