In view of the importance and typicality of copper , iron sulfide and mixed sulfides in mineral resources and its wet treatment, this paper takes Cu-Fe-S-H 2 O system as an example to discuss the advantage zone in wet the rule of law in the application of gold. Figure 1 is a diagram of the dominant area of ​​the Cu-Fe-S-H 2 O system at 298 K and 1 atm total pressure. This map can help mineralogists understand the relationship between the oxidation zone and the secondary enrichment zone in the deposit, and also help hydrometallurgists understand the oxidative leaching process of copper-iron sulfide minerals. The map of the dominant area of ​​the Cu-Fe-S-H 2 O system is quite complex at first glance, with a little attention, that is, seeing clues. Variety of copper, copper - iron and an iron sulfide is quite clear from the E h -pH with the oxide of copper and iron are separated, the E h -pH E h with from about 0.3, pH = 0 impose each pH The slope of the unit 60mV extends to the right, and only the copper ore extends this boundary, which is consistent with the secondary enrichment of copper ore to produce a copper ore layer. It is worth noting that Cu 2 + and Fe 2 + are produced in solution when equilibrated under acidic conditions, and Cu 2 + and Fe 2 O 3 (or Fe 2 O 3 ·H 2 are produced at slightly lower acidity). O). The reason for the separation of iron and copper during oxidation is reflected. The dominant area map identifies copper minerals such as chalcopyrite, copper blue, porphyrite and chalcopyrite, as well as pH and potential zones stabilized by pyrrhotite, pyrite and elemental sulfur. From the perspective of hydrometallurgy, the figure can also be used to determine the nature of the aqueous solution that will decompose the minerals, and also to understand what new solid or gaseous products are formed during mineral decomposition. Of course, the advantage zone map does not tell us the speed of mineral decomposition. Figure 1 Advantage map of Cu-Fe-S-H 2 O system (298K, 1atm, dissolved total sulfur 10 -1 mol∕L) It can be seen from the figure that sulfide minerals may decompose in the following four different solutions. (1) An oxidizing solution. Sulfurized minerals may oxidize to form elemental sulfur or sulfate depending on the selected oxidation potential and pH. (2) Strong acid solution. The sulfide mineral is liberated by acid to release H 2 S to dissolve copper and iron. (3) Reducing solution. The sulfide mineral reduction fraction liberates H 2 S or sulfide ions as well as metal low-valent sulfides or metals. (4) Strong alkaline solution. Sulfide minerals are decomposed by alkali to produce sulfide ions and metal oxides (or low-valent sulfides). The above four solution systems are generally applicable to all metal sulfides, but strong acid solutions and strong alkali solutions sometimes require too high a strength, and the actual aqueous solution does not. The oxidizing solution and the reducing solution can be further divided into acidic and basic systems, respectively. Taking chalcopyrite as an example, its oxidation in the acidic region (pH = 0) can be expressed by the following chemical formula: or The reaction (d) is a reaction for producing copper blue, which is derived from the stable elemental sulfur in the figure. This reaction was observed by anodization in a pressurized system at 130 ° C in the laboratory. The reaction (e) is observed in a hydrothermal system at 160-230 ° C and is patented for hydrometallurgical purposes and can be considered as an activation process prior to leaching of chalcopyrite. However, visible copper blue products have never been observed in any atmospheric or pressure leaching studies. Reaction (f) oxidizes chalcopyrite at a low potential to produce a chalcopyrite. The reaction rate is too slow and cannot be observed under laboratory conditions. However, this reaction is very important in geology, which explains the presence of chalcopyrite in copper oxide ore. It may also be an important reaction in the heap where bacteria accelerate the oxidation of chemically slow sulfur. Reaction (f) is a common reaction in laboratory leaching experiments, especially at high pH values ​​such as in ammonia leaching. In acidic oxidative leaching, this formula explains why the oxidation of sulfur is below 1% to more than 30% due to pH and oxidant. The equations (a)-(g) explained from the dominant zone diagram do not explain the dominant reaction observed in acidic oxidative leaching. This dominant reaction can be described by the reaction formula (h): In fact, Cu 2 + is an oxidant that oxidizes sulfur, so the above formula is the only reaction found. The irreversible oxidation of sulfur to sulfate (at least in an acidic solution) is very difficult, and the reaction rate of the reaction (h) is very advantageous compared to the previous seven reactions. A new map that is more useful for hydrometallurgy can be obtained by omitting the equilibrium line of the unrecognized reaction on the map of the dominant area (in the laboratory rather than in the geological sense). For example, the reactions (a) to (b) are omitted, that is, H 2 S cannot be supplied as a reactant, or pyrite cannot be produced at an appropriate rate, and the stable region of the chalcopyrite is expanded. At this time, the map still contains some reactions that can only be observed at very high temperatures or long geological times. These reactions can provide a more useful tool for hydrometallurgy.
All of the Case parts we provide is replacement parts with high quality, and main of them are agriculture and construction machinery parts, like for tractors, excavators, different type of loaders, forklifts and so on. Case is a giant company who supply a wide range of machines to the world, and they cooperate with Cummins, Mitsubishi, Yanmar, Iveco for their power plant. So we can offer lots of Engine Parts for Case equipments. Except for these parts, we could also supply lamps for Case which are used for backhoe loader, like 570, 580, 590 series.
Case Ih Aftermarket Parts,Case Ih Parts,Aftermarket Ih Tractor Parts,Case Ih Parts Dealers Hangzhou Holdwell Mechanical&Electrical Co.,LTD , https://www.dieselpart.nl
