Salts roasting

Vanadium raw materials are processed to produce vanadium chemicals, eg, the pentoxide and ammonium metavanadate (AMV) primary compounds, by salt roasting or acid leaching. Interlocking circuits, in which unfinished or scavenged material from one process is diverted to the other, are sometimes used. Such interlocking to enhance vanadium recovery and product grade became more feasible in the late 1950s with the advent of solvent extraction. 

For direct precipitation of vanadium from the salt-roast leach Hquor, acidulation to ca pH 1 without the addition of ammonia salts yields an impure vanadic acid when ammonium salts are added, ammonium polyvanadate precipitates. The impure vanadic acid ordinarily is redissolved in sodium carbonate solution, and ammonium metavanadate precipitates upon addition of ammonium salts. Fusion of the directly precipitated ammonium salts can yield high purity V20 for the chemical industry. Amine solvent extraction is sometimes used to recover 1—3 g/L of residual V20 from the directly precipitated tail Hquors. 

Australian Vanadium—Uranium Ore. A calcareous camotite ore at YeeHrrie, AustraHa, is iU-suited for salt roasting and acid leaching. Dissolution of vanadium and uranium by leaching in sodium carbonate solution at elevated temperature and pressure has been tested on a pilot-plant scale... 

Vanadium pentoxide Salt roasting V2Os + 2 NaCl + H20 - Na2V206 + 2 HC1 Water leaching... 

Salt retention, by colloidal silica and silica sols, 22 392 Salt roasting... 

In the treatment of complex sulfide concentrates containing copper, nickel, cobalt, lead, and iron, roasting with a moderate excess of sodium chloride at temperatures up to 400°C prior to leaching with hydrochloric acid has been succeasfully used by Kershner and Hoertel (K4) in the recovery of more than 95% of cobalt, nickel, and copper. The chloridized product is treated with steam at 300°C to make most of the iron insoluble before leaching at a pH of 1.0. The advantages of a salt roast prior to... 

Table 9.2-2 summarizes the various methods used for the treatment of direct leaching ores. Typical minerals are listed, and those that can be leached by sonoxidative dissolution (NOX) are indicated. Those requiring oxidants (OX) are also indicated. In some cases preireaiment is required, as in the case of reduction masting of nickel laleriles or vanadium ore which may be subjednd to an oxidative salt roast prior to nonoxidative dissolution. Also indicated in Table 9.2-2 are the typical lixiviants used in the process, the methods used for metal recovery, and the form of the fianl product produced. 

Raw macadamia nuts can be bought whole or, because they are quite large, in halves as individual snacks. To enhance the flavor, they can be dry roasted and are also available roasted and salted, roasted and smoked, and roasted with barbeque flavor. Because of the high fat content the nuts can quickly become rancid so they are usually sold in vacuum-packed containers. Once opened, they should be stored in the fridge or freezer. 

Chickpeas (Abo see LEGUMES, Table L-2.) Salted roasted chickpeas or uncooked dried chickpeas. Roasted peas—as a snack like peanuts. Boiled peas—as most other dried legumes. Similar lo that ol most legumes. Canned cooked chickpeas ate eold in many American supermarkets. 

Traditional dish of American Indians of the southwest, prepared from a thin batter of blue maize meal, ash, and water. The batter is cooked on a hot flat stone to form a parchment-like product. Piki can be crumbled, salted, roasted, and eaten like chips. 

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