Metal oxides and their composites have been extensively studied as effective adsorbents for the removal of heavy metals from aqueous solutions in environmental remediation. In this work, Cu 0.5 Mg 0.5 Fe 2 O 4 was synthesized by a co-precipitation method followed by calcination (900 °C) and investigated for Pb(II) adsorption. The resultant samples were characterized by various analytical techniques including X-ray diffraction, N 2 adsorption−desorption, scanning electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The results revealed that single-phase cubic spinel was obtained by the calcination of assynthesized samples at a temperature of 900 °C. Cu 0.5 Mg 0.5 Fe 2 O 4 ferrite is a mesoporous material with a surface area, a total pore volume, and an average pore size of 41.3 m 2 /g, 0.2 cm 3 /g, and 15.1 nm, respectively. Pb(II) adsorption on Cu 0.5 Mg 0.5 Fe 2 O 4 fitted well to the Langmuir model, indicating monolayer adsorption with a maximum capacity of 57.7 mg/g. The pseudo-second-order kinetic model can exactly describe Pb(II) adsorption with the normalized standard deviation (Δq) of 1.24%. The obtained results confirmed that the Cu 0.5 Mg 0.5 Fe 2 O 4 ternary oxides exhibit a high adsorption capacity toward Pb(II), thanks to the increase in active adsorptive sites of ferrite.

The use of nano-additives is widely recognized as a cheap and effective pathway to improve the performance of lubrication by minimizing the energy loss from friction and wear, especially in diesel engines. In this work, a simple and scalable protocol was proposed to fabricate a graphene additive to improve the engine lubricant oil. Graphene nanoplates (GNPs) were obtained by a one-step chemical exfoliation of natural graphite and were successfully modified with a surfactant and an organic compound to obtain a modified GNP additive, that can be facilely dispersed in lubricant oil. The GNPs and modified GNP additive were characterized using scanning electron microscopy, X-ray diffraction, atomic force microscopy, Raman spectroscopy, and Fourier-transform infrared spectroscopy. The prepared GNPs had wrinkled and crumpled structures with a diameter of 10–30 µm and a thickness of less than 15 nm. After modification, the GNP surfaces were uniformly covered with the organic compound. The addition of the modified GNP additive to the engine lubricant oil significantly enhanced the friction and antiwear performance. The highest reduction of 35% was determined for the wear scar diameter with a GNP additive concentration of approximately 0.05%. The mechanism for lubrication enhancement by graphene additives was also briefly discussed.

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In this study, the self-assembly of 5,10,15,20-tetra(3,4,5-trimethoxyphenyl)porphyrin (coded as: TTOP) in the mixture of tetrahydrofuran (THF) and H2O and the photocatalytic activity of resulting self-assembled aggregates toward the degradation of...

Fe2O3-TiO2 nanoparticles promises as a highly effective material for adsorption of heavy metals and used as photocatalyst for the removal of organic dye pollutants. In this study, nanostructured Fe2O3-TiO2 composite was successfully fabricated by one-step reaction of ilmenite ore at the high temperature in ambient condition. The resultant Fe2O3-TiO2 composite was characterized by using X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherm. The effects of sintered temperature and time on the formation of the Fe2O3-TiO2 nanocomposite were investigated in detail. The Fe2O3-TiO2 was formed from ilmenite ore after calcination at the temperature of 700 o C in 3 hours, followed by a ball-milled process in 4 hours. The obtained Fe2O3-TiO2 composite has an average diameter of from 50 -100 nm with the BET surface area of 7 m 2 /g. Keywords-Ilmenite,Fe 2 O 3 -TiO 2 , nanocomposite, mixed oxides, ore processing. I.