279. The system magnesium oxide–magnesium chloride–water

1932 ◽  
Vol 0 (0) ◽  
pp. 2008-2015 ◽  
Author(s):  
C. R. Bury ◽  
E. R. H. Davies
Keyword(s):  
Magnesium Oxide ◽  
Magnesium Chloride ◽  
Chloride Water

Solution-Based Synthesis of Magnesium Oxide Nanorods

1999 ◽  
Vol 581 ◽  
Author(s):  
Q. Wei ◽  
C.M. Lieber
Keyword(s):  
Electron Microscopy ◽  
Magnesium Oxide ◽  
Magnesium Chloride ◽  
Low Cost ◽  
Industrial Applications ◽  
Transformation Process ◽  
Matrix Composites ◽  
X Ray ◽  
Transmission Electron ◽  
Oxide Nanorods

ABSTRACTA solution-based synthesis route was developed to produce large quantities of MgO nanorods. Hydrated basic magnesium chloride, which has needle-like crystal structure, was used as a precursor. A subsequent two-step transformation process with magnesium hydroxide as an intermediate product was used to preserve the morphology of the precursor to yield magnesium oxide nanorods. Scanning electron microscopy, powder X-ray diffraction and energy dispersive X-ray spectroscopy show that the products are very pure (>95%) crystalline MgO nanorods with diameters from 40 nm to 200 nm and lengths 10 microns or longer. High-resolution transmission electron microscopy and electron diffraction further reveal that these MgO nanorods are single crystals and that the rod axis is along the <110> crystal direction. A model for the structural transformation from hydrated basic magnesium chloride to magnesium oxide has been developed and compared to our experimental results. This solution-based process can be easily scaled-up, and is a low-cost source of pure magnesium oxide nanorods needed in many industrial applications, for example, as reinforcing agents in matrix composites and as flux-pinning centers in high-TC superconductors.

scholarly journals STUDY ON THE REMOVAL OF AMMONIA IN WASTEWATER USING ADSORBENT PREPARED FROM RICE HULL WITH MAGNESIUM OXIDE MODIFICATION

2020 ◽  
Vol 58 (3A) ◽  
pp. 113
Author(s):  
Thuy Nguyen Thi ◽  
Van Tran Dang Lan ◽  
Hoan Nguyen Xuan ◽  
Son Le Thi Bich ◽  
Mai Tran Thi Ngoc ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Magnesium Oxide ◽  
Removal Efficiency ◽  
Magnesium Chloride ◽  
Domestic Wastewater ◽  
Adsorption Kinetic ◽  
Rice Hull ◽  
Ammonium Concentration ◽  
Chloride Salt ◽  
Ammonium Removal

This study is aimed to evaluate the ability of magnesium oxide-coated carbonized rice hull (MCRH) material for ammonium removal in synthetic and real domestic wastewater. The MCRH material was prepared using waste rice hull from a household rice-processing factory and magnesium chloride salt via a simple mixing and annealing method. The material was then characterized by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The effects of magnesium chloride modification and environmental condition such as initial ammonium concentration (20 – 100 mg/L), amount of adsorbent (0.8 –2.0 g/L), and adsorption time (0 –32 h) on the ammonium removal efficiency and adsorption capacity were investigated. Adsorption kinetic and isotherms were also studied for MCRH material. Results showed that magnesium oxide was successfully coated on carbonized rice hull with Mg/C molar ratio of 0.22. Ammonium adsorption isotherm fitted well to Langmuir model with maximum adsorption capacity of 65.36 mg/g. The adsorption was physical process and adsorption kinetic was best described by intra-particle diffusion model with the correlation coefficients ranged from 0.942 – 0.979. Ammonium removal feasibility of MCRH was proved through the treatment of real domestic wastewater containing 80.7±1.6 mg/L initial ammonia concentration with removal efficiency reached 86.8% and the effluent concentration met the allowable value (10 mg/L) as given by QCVN 14 : 2008/BTNMT (column B) - National technical regulation on domestic wastewater. Hence MCRH is potential as a cheap and abundant material in Vietnam and the material after adsorption accumulated ammonium would be the source of fertilizer for soil quality improvement.

Sign in / Sign up

Export Citation Format

Share Document