Iron reduction technique

Information concerning the pathways and products of reactions of polyhalogenated solvents with zero-valent metals may be critical to the success of in situ treatment techniques. Fennelly and Roberts (1998) have investigated the reduction of 1,1,1-trichloroethane (1,1,1 -TCA) by Fe(O) and Zn(O) and by two bimetallic (nickel/iron and copper/iron) reductants. The following products were detected at measurable concentrations as intermediates and/or final products ... 

Naturally iron and steel are the materials of particular interest in corrosion research. To get an idea of the action of irradiation-induced defects on the oxide layer of iron, Ashworth et al. made measurements using an electrometric reduction technique which gives the thickness of the oxide layer as well as its composition. 

Chemical analysis Chemical analyses on suspension or powder samples were performed by a volumetric method (0.05 normal potassium dichromate) following dissolution in hydrochloric acid. The ferrous (Fe2+) content was determined directly. The ferric (Fe3+) content was analyzed via the Zimmermann-Reinhardt (SnCl2 reduction) technique, which gives the total iron. Subtraction of the Fe2+ gives the desired Fe3+ value. The Fe2+/Fe3+ ratio was determined with an accuracy of 0.01. The accuracy of the determination of the total iron was 0.5% of the result. Chloride content was determined by Volhard titration with an accuracy of 5% of the result. Nitrogen content was analyzed with the Nessler method with a relative accuracy of 15%. 

They investigated both the fresh and spent catalysts by using temperature programmed reduction technique. The bimetallic catalysts exhibit much lower Au reduction temperature compared to Au/Fc203. The X-ray diffraction measurements show that there is no evidence for mixed metal species (Au-Ru) either in fresh or spent catalysts. TPR analysis of the spent Au-Ru/iron oxide catalyst revealed the presence of the reduction signal due to AU Oy species at a Tmax of 155 °C, which suggests the lowering in the reduction temperature which is found at 161 °C in the Au-Ru/iron oxide fresh catalyst. 

Electro-reduction deserves further attention as, by applying this technique for iron reduction and stripping, neither chemicals, reductive metals or alloys, nor an autoclave is needed. Because D2EHPA is frequently referenced as the standard for iron extraction from acidic sulphate solutions, especially for Fe/Zn separation, we decided to study some aspects of the electro-reduction of Fe (III)-loaded D2EHPA. 

Magnetic iron/iron oxide nanoparticles were prepared by an in situ chemical reduction technique in a combination of PANI-polyacrylamide (PA) and PANl-Mesua ferrea L. seed oil-based HBPU matrices. A reduced size with better dispersion and more stable nanoparticles was found in HBPU... 

Pennock et al. investigated the catalysts before and after reduction by in situ TEM reduction techniques. They observed iron cyrstals and the pore structure of approximately 20 nm-30 nm and indicated that the pores in magnetite grow along with (111) face. The same morphological trends of all of iron crystals are found in certain fields, namely, the crystal (100) face of both iron and magnetite are paralleled, while that (010) face, (001) face of iron are paralleled with (Oil) face, (Oil) face of magnetite. 

Worldwide demand for blast furnace coke has decreased over the past decade. Although, as shown in Figure 1, blast furnace hot metal production (pig iron) increased by about 4% from 1980 to 1990, coke production decreased by about 2% over the same time period (3). This discrepancy of increased hot metal and decreased coke production is accounted for by steady improvement in the amounts of coke required to produce pig iron. Increased technical capabihties, although not universally implemented, have allowed for about a 10% decrease in coke rate, ie, coke consumed per pig iron produced, because of better specification of coke quaUty and improvements in blast furnace instmmentation, understanding, and operation methods (4). As more blast furnaces implement injection of coal into blast furnaces, additional reduction in coke rate is expected. In some countries that have aggressively adopted coal injection techniques, coke rates have been lowered by 25% (4). 

Developments in the metallurgy of copper or its alloys were mentioned in 1556 in De MetalBca where the process of copper ore was described by Agricola (see also Copper alloys). About that time, smelting operations commenced at Mansfield, Germany, and at the Swansea smelter in Wales. Both smelters employed successive oxidations and reductions to eliminate iron and sulfur. The process used in the Swansea smelter is similar to modern techniques. 

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