Mathod of metal Extraction from Ore
One-grinding-concentration, decantation, filling smelting, reduction of metal oxide, metal refining and pure metal recovery.
Extraction of modified from concentrated ores
Separation of metal from crude ores takes place in the following three main terms.
Change in oxide
This is achieved by the following two processes.
Calcination-
The process of heating an ore from its melting point to a lower temperature sequence in absence or air is called dislocation. Metal crbonates, disposes, hydroxides and oxides.
Roasting-
The process of heating the ore below its melting point in the presence of air is called Roasting. this is only for sulfide ores.
Reduction of Oxide in Metal-
Reduction of oxide in metal is done as follows-
Smelting-
It is reduction by carbon or its oxides. Reduction of metals located in the middle of the activation range is done by this method.
The process of heating the ore by mixing it with coke and sulfur at a temperature above its melting point is called effluent. Oxides of metals like lead, iron, tin, zinc etc. are reduced by this method. This method is used for smelting the entire mixture and reducing the metal oxides to the metal. Examples- PbO + C →2Pb(molten lead) + CO2
Aluminothermic Process-
Oxides of metals like chromium, manganese etc. are reduced by aluminum.
Auto-Reduction-
Metals falling below the activation range are much less active. Only by heating of oxides of these metals, metal can be obtained. Example- Copper, mercury, lead are reduced by this method.
Electrolytic Method-
This method is used for metals at the top of the activation range such as sodium, calcium, aluminum. By this method their oxides are reduced to metal. Sodium is obtained as a result of the decomposition of sodium chloride.
कोई टिप्पणी नहीं:
एक टिप्पणी भेजें