136 results about "Iron(III) oxide-hydroxide" patented technology

The present invention relates to a method for preparing liquid or solid hydrocarbons from syngas via the Fischer-Tropsch synthesis in the presence of iron-based catalysts, the iron-based catalysts for the use thereof, and a method for preparing the iron-based catalysts; more specifically, in the Fischer-Tropsch reaction, liquid or solid hydrocarbons may be prepared specifically with superior productivity and selectivity for C5+ hydrocarbons using the iron-based catalysts comprising iron hydroxide, iron oxide, and iron carbide wherein the number of iron atoms contained in the iron hydroxide is 30% or higher, and the number of iron atoms contained in the iron carbide is 50% or lower, relative to 100% of the number of iron atoms contained in the iron-based catalysts.

An atmospheric leach process in the recovery of nickel and cobalt from lateritic ores, said processing including the steps of: a) separating the lateritic ore into a low magnesium containing ore fraction, and a high magnesium containing ore fraction by selective mining or post mining classification; b) separately slurrying the separated ore fractions; c) leaching the low magnesium containing ore fraction with concentrated sulphuric acid as a primary leach step; and d) introducing the high magnesium content ore slurry following substantial completion of the primary leach step and precipitating iron as goethite or another low sulphate containing form of iron oxide or iron hydroxide, wherein sulphuric acid released during iron precipitation is used to leach the high magnesium ore fraction as a secondary leach step.

The present invention provides a method for separating and recycling arsenic and iron form the biological oxidation solution of sulfide ore and belongs to the technique. According to the method, firstly magnesium oxide is added into the biological oxidation solution of sulfide ore, then the pH value is adjusted to 5-6 so that the arsenic and iron in the biological oxidation solution generate coprecipitation, and the precipitate comprising iron and arsenic precipitate and the neutralizing agent are obtained through separating. Then the lime is added into the neutralizing solution so that the pH value obtains 8-10. The magnesium sulfate in the neutralizing agent and the lime generate calcium sulfate and magnesium hydroxide precipitate. The precipitate containing calcium sulfate and the treated water are separated. The separated water returns to the production system and the precipitate is recycled as the building material. After the coprecipitate is dried, water is added for leaching the magnesium sulfate in the coprecipitate. The precipitate after leaching and the water extract are separated. The water extract is combined with the neutralizing agent for entering the processing operation of the neutralizing agent. The arsenic in the precipitate after leaching is leached by the sodium hydroxide solution, and the arsenic leaching solution and the iron hydroxide precipitate are obtained after separation. The arsenic leaching solution is heated, evaporated and condensed to the arsenic content of 40g / L-60g / L. Then the solution is cooled for crystallizing. The sodium arsenate and the crystal mother liquor are obtained through separation. The mother liquor returns to the arsenic leaching system.

In ridding fluids, including hydrocarbon fluids, both gaseous and liquid, of sulfur compounds including hydrogen sulfide, oxides of sulfur, and thiols, the present invention uses a small quantity of an activator, generally a noble metal oxide, preferably a copper species and / or a manganese species, along with a known oxide product, such as iron oxide, iron hydroxide, zinc oxide, zinc hydroxide, manganese oxide, manganese hydroxide, or combinations thereof, to thoroughly remove sulfur contaminants in a short amount of time. The activator allows for the use of smaller reactor vessels and the production of hydrocarbon fluids substantially free of sulfur products.

The invention relates to a method for removing multiple pollutants in copper smelting waste acid by using Bayer process red mud. The method comprises the steps of oxidizing trivalent arsenic into pentavalent arsenic in the waste acid by using a way of continuously aerating while heating; then, adding Bayer process red mud particles, controlling an arsenic-iron molar ratio and a pH value, forming amorphous iron arsenate by using iron in the Bayer process red mud and arsenic in the copper smelting waste acid, and then oxidizing to form stable iron arsenate so as to remove the arsenic in the waste acid and absorb the multiple pollutants in the waste acid. After the scheme is adopted, iron salt used for treating the arsenic does not need to be additionally added, so that the economic cost is reduced; the method realizes the co-disposal of the solid waste produced by the copper smelting industry and the Bayer process red mud produced by the alumina industry, and reduces the secondary pollution to the environment. The method also can obtain iron hydroxide with an economic value by controlling the pH value while changing the Bayer process red mud waste into valuable and treating the wasteacid; due to the increment and decrement of input cost, an enterprise can obtain considerable economic benefit.

The present invention relates to a process for the preparation of iron-oxide- and / or iron-oxyhydroxide-containing ion exchangers by polymerizing iron-oxide- and / or iron-oxyhydroxide-containing mixtures and functionalizing the resultant polymers.