Metal sulfides based composites as promising efficient microwave absorption materials: A review

2022 ◽  
Vol 104 ◽  
pp. 244-268
Author(s):  
Bin Li ◽  
Fenglong Wang ◽  
Kejun Wang ◽  
Jing Qiao ◽  
Dongmei Xu ◽  
...  
Keyword(s):  
Microwave Absorption ◽  
Metal Sulfides

Scanning Electron Microscope Study of Bacteria on Mineral Surfaces

1976 ◽  
Vol 34 ◽  
pp. 130-131
Author(s):  
V.K. Berry
Keyword(s):  
Oxidation Reaction ◽  
Electron Microscope Study ◽  
Elemental Sulfur ◽  
Thiobacillus Ferrooxidans ◽  
Physical Contact ◽  
Metal Sulfides ◽  
Low Grade ◽  
Mineral Surfaces ◽  
Mineral Surface ◽  
Scanning Electron Microscope Study

There are two strains of bacteria viz. Thiobacillus thiooxidansand Thiobacillus ferrooxidanswidely mentioned to play an important role in the leaching process of low-grade ores. Another strain used in this study is a thermophile and is designated Caldariella .These microorganisms are acidophilic chemosynthetic aerobic autotrophs and are capable of oxidizing many metal sulfides and elemental sulfur to sulfates and Fe2+ to Fe3+. The necessity of physical contact or attachment by bacteria to mineral surfaces during oxidation reaction has not been fairly established so far. Temple and Koehler reported that during oxidation of marcasite T. thiooxidanswere found concentrated on mineral surface. Schaeffer, et al. demonstrated that physical contact or attachment is essential for oxidation of sulfur.

Identification of acid-insoluble filter-plugging compounds and optimal acid-washing procedures for tubular backpulse pressure filters

TAPPI Journal ◽  
2011 ◽  
Vol 10 (1) ◽  
pp. 17-23
Author(s):  
KEVIN TAYLOR ◽  
RICH ADDERLY ◽  
GAVIN BAXTER
Keyword(s):  
Calcium Sulfate ◽  
Membrane Filter ◽  
Sulfamic Acid ◽  
Xrd Analysis ◽  
Metal Sulfides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gypsum Formation ◽  
Acid Washing ◽  
Hydrolysis Of

Over time, performance of tubular backpulse pressure filters in kraft mills deteriorates, even with regular acid washing. Unscheduled filter replacement due to filter plugging results in significant costs and may result in mill downtime. We identified acid-insoluble filter-plugging materials by scanning electron microscope/energy-dispersion X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) analysis in both polypropylene and Gore-Tex™ membrane filter socks. The major filter-plugging components were calcium sulfate (gypsum), calcium phosphate (hydroxylapatite), aluminosilicate clays, metal sulfides, and carbon. We carried out detailed sample analysis of both the standard acid-washing procedure and a modified procedure. Filter plugging by gypsum and metal sulfides appeared to occur because of the acid-washing procedure. Gypsum formation on the filter resulted from significant hydrolysis of sulfamic acid solution at temperatures greater than 130°F. Modification of the acid-washing procedure greatly reduced the amount of gypsum and addition of a surfactant to the acid reduced wash time and mobilized some of the carbon from the filter. With surfactant, acid washing was 95% complete after 40 min.

Microwave wide band absorption by carbon from Corn cob-1

2016 ◽  
Vol 12 (2) ◽  
pp. 4204-4212 ◽  
Author(s):  
Maheshwar Sharon ◽  
Ritesh Vishwakarma ◽  
Abhijeet Rajendra Phatak ◽  
Golap Kalita ◽  
Nallin Sharma ◽  
...  
Keyword(s):  
Microwave Absorption ◽  
Agricultural Waste ◽  
Wide Band ◽  
Nickel Nitrate ◽  
Equivalent Amount ◽  
Frequency Range ◽  
Corn Cob ◽  
Different Temperatures ◽  
Band Absorption ◽  
5 Ghz

Corn cob, an agricultural waste, is paralyzed at different temperatures (700oC, 800oC and 900oC). Microwave absorption of carbon in the frequency range of 2 GHz to 8 GHz is reported. Carbon activated  with 5%  nickel nitrate showed more than 90% absorption of microwave in the frequency range from 6 GHz to 8 GHz, while carbon activated  with 10% Nickel nitrate treated corn cob showed 90% absorption  in the frequency range of 2.5 GHz to 5 GHz. Carbon showing the best absorption are characterized by XRD, Raman spectra and SEM . It is suggested that corn cob treatment   alone with KOH did not improve the microwave absorption, whereas treatment along with nickel nitrate improved the absorption property much better. It is proposed that treatment with nickel nitrate helps in creating suitable pores in carbon   which improved the absorption behavior because while treating carbon with 1N HCl helps to leach out nickel creating equivalent amount of pores in the carbon.

Preparation and Microwave Absorption Properties of LiZn Ferrite

2009 ◽  
Vol 25 (1) ◽  
pp. 73-76 ◽  
Author(s):  
Hong JIANG ◽  
Jia GUO ◽  
Lu ZHAO ◽  
Hong ZHU
Keyword(s):  
Microwave Absorption ◽  
Absorption Properties ◽  
Microwave Absorption Properties

Synthesis and Microwave Absorption of the Silica-coated Fe Nanocomposites

2009 ◽  
Vol 24 (2) ◽  
pp. 340-344 ◽  
Author(s):  
Deng-Ke WANG ◽  
Hao HUANG ◽  
Kuai YU ◽  
Xue-Feng ZHANG ◽  
Xing-Long DONG
Keyword(s):  
Microwave Absorption

Metal Sulfides/Graphene Nanocomposites: An Overview of Preparation and Applications

2014 ◽  
Vol 6 (3) ◽  
pp. 152-160 ◽  
Author(s):  
Xiaoshuang Zheng ◽  
Jingdong Liu ◽  
Long Chen ◽  
Jianping Gao ◽  
Yousheng Tao
Keyword(s):  
Metal Sulfides ◽  
Graphene Nanocomposites

The Effect of γ-Al2O3, TiO2 and ZrO2 Supports on Hydrodesulfurization Activity of Transition-Metal Sulfides

2008 ◽  
Vol 73 (8-9) ◽  
pp. 945-955 ◽  
Author(s):  
Luděk Kaluža ◽  
Miroslav Zdražil
Keyword(s):  
Transition Metal ◽  
Aqueous Solutions ◽  
Model Reaction ◽  
Metal Sulfides ◽  
Vacuum Impregnation ◽  
Transition Metal Sulfides ◽  
Highly Active ◽  
System A ◽  
Benzothiophene Hydrodesulfurization ◽  
Hydrodesulfurization Activity

The transition metals V, Cr, Mn, Fe, Co, Ni, Mo, Ru, Rh, Pd, W, Re, Os, Ir and Pt were deposited from aqueous solutions of their salts onto conventional γ-Al2O3 and unconventional TiO2 and ZrO2 supports by vacuum impregnation and characterized in their sulfided form by a model reaction of benzothiophene hydrodesulfurization. It was found that the TiO2 and ZrO2 supports influenced predominantly positively the resulting activity of relatively low-active metals (V, Cr, Mn, Fe, Co, Ni, Mo, Ru, W and Os), whereas the highly active metals (Rh, Pd, Ir, Pt and Re) were influenced slightly negatively or not at all by those supports compared with the γ-Al2O3-supported system. A significant effect of the supports on the hydrodesulfurization-activity ranking of the transition-metal sulfides studied was ascertained.

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