The adsorption of aluminium(III) and iron(III) ions from their single and binary systems, by RHAC was investigated in a batch system. The activated carbon prepared from rice hulls was characterized by scanning electro...The adsorption of aluminium(III) and iron(III) ions from their single and binary systems, by RHAC was investigated in a batch system. The activated carbon prepared from rice hulls was characterized by scanning electron microscopy and Fourier transformation infrared techniques. Batch adsorption experiments were performed under different operating conditions including pH (2 - 5), adsorbent dosage (0.5 - 2.0 g/l), initial ion concentration (5 - 100 mg/l), and contact time (30 - 240 min). The equilibrium time for maximum ions removal was found to be 180 min in single and binary ions systems. The kinetics of adsorption was evaluated using the pseudo-first order, pseudo-second order and Elovich kinetic models. The Langmuir, Freundlich and Temkin equilibrium models were applied to the adsorption experimental data. Real wastewater samples were collected from different locations to investigate the efficiency of rice hull activated carbon in treating real samples. The real wastewater samples were treated with the activated carbon prepared from rice hulls and a commercial activated carbon. The results showed that the activated carbon prepared in the present work was more efficient in the removal of aluminium and iron from real wastewater as compared to the commercial activated carbon which is more advantageous considering both economics and environmental parameters.展开更多
Metallic coatings of many types can be applied to steel to provide outstanding, long-term corrosion protection. A thin A1 film is studied at an Fe substrate by the molecular dynamics method at temperatures ranging fro...Metallic coatings of many types can be applied to steel to provide outstanding, long-term corrosion protection. A thin A1 film is studied at an Fe substrate by the molecular dynamics method at temperatures ranging from 300 K to 1173 K. A1 atoms are found to penetrate the Fe matrix at a temperature of 873 K. The potential energy of the system changes step-like at a temperature of 1173 K. At such temperature mean square atomic displacement significantly changes. The behaviors of the A1 and Fe diffusion coefficients are mainly determined by the temperature dependence of the diffusion activation energy.展开更多
The composition,structure and micro-morphology of magnesium- iron- aluminum composite oxides were investigated using various methods such as XRF,SEM,EDS,XRD and KMn O4-titration. Compared to hercynite,the composite ox...The composition,structure and micro-morphology of magnesium- iron- aluminum composite oxides were investigated using various methods such as XRF,SEM,EDS,XRD and KMn O4-titration. Compared to hercynite,the composite oxides have completely different phases including solid solution（ Mg O）0. 77（ Fe O）0. 23,composite spinel Mg Fe0. 2Al1. 8O4 and a small amount of Mg Fe2O4. The composite oxides exhibit excellent corrosion resistance to cement clinker and potassium salts.The products produced by magnesite and the composite oxides show better performance than magnesia- hercynite bricks,especially the corrosion resistance and thermal shock resistance.展开更多
文摘The adsorption of aluminium(III) and iron(III) ions from their single and binary systems, by RHAC was investigated in a batch system. The activated carbon prepared from rice hulls was characterized by scanning electron microscopy and Fourier transformation infrared techniques. Batch adsorption experiments were performed under different operating conditions including pH (2 - 5), adsorbent dosage (0.5 - 2.0 g/l), initial ion concentration (5 - 100 mg/l), and contact time (30 - 240 min). The equilibrium time for maximum ions removal was found to be 180 min in single and binary ions systems. The kinetics of adsorption was evaluated using the pseudo-first order, pseudo-second order and Elovich kinetic models. The Langmuir, Freundlich and Temkin equilibrium models were applied to the adsorption experimental data. Real wastewater samples were collected from different locations to investigate the efficiency of rice hull activated carbon in treating real samples. The real wastewater samples were treated with the activated carbon prepared from rice hulls and a commercial activated carbon. The results showed that the activated carbon prepared in the present work was more efficient in the removal of aluminium and iron from real wastewater as compared to the commercial activated carbon which is more advantageous considering both economics and environmental parameters.
基金Project supported by the Ministry of Science and Education of the Russian Federation(Grant No.14.607.21.0035,unique identifier RFMEFI60714X0035)
文摘Metallic coatings of many types can be applied to steel to provide outstanding, long-term corrosion protection. A thin A1 film is studied at an Fe substrate by the molecular dynamics method at temperatures ranging from 300 K to 1173 K. A1 atoms are found to penetrate the Fe matrix at a temperature of 873 K. The potential energy of the system changes step-like at a temperature of 1173 K. At such temperature mean square atomic displacement significantly changes. The behaviors of the A1 and Fe diffusion coefficients are mainly determined by the temperature dependence of the diffusion activation energy.
文摘The composition,structure and micro-morphology of magnesium- iron- aluminum composite oxides were investigated using various methods such as XRF,SEM,EDS,XRD and KMn O4-titration. Compared to hercynite,the composite oxides have completely different phases including solid solution（ Mg O）0. 77（ Fe O）0. 23,composite spinel Mg Fe0. 2Al1. 8O4 and a small amount of Mg Fe2O4. The composite oxides exhibit excellent corrosion resistance to cement clinker and potassium salts.The products produced by magnesite and the composite oxides show better performance than magnesia- hercynite bricks,especially the corrosion resistance and thermal shock resistance.
