11 results about "Low magnesium" patented technology

The invention belongs to the technical field of inorganic salt chemical industry. The invention provides a method for preparing anhydrous lithium chloride by using salt lake brine with low magnesium-lithium ratio, which comprises the following steps: pumping clear salt lake brine with low magnesium-lithium ratio into a plate-and-frame filter press for filtration, and sequentially performing microporous filtration and ultrafiltration on filtrate to obtain primary refined brine; filtering the primary refined brine through a nanofiltration membrane device to obtain secondary refined brine; allowing the secondary refined brine to pass through chelating resin to obtain magnesium-removed brine; mixing the magnesium-removed brine with an alkali solution, adjusting the pH value of the mixed solution, and pumping the mixed solution into a continuous extraction device for solvent extraction to obtain a lithium chloride solution; and evaporating and drying the lithium chloride solution in sequence to obtain an anhydrous lithium chloride product. The anhydrous lithium chloride product is prepared by adopting a nanofiltration membrane separation and solvent extraction combined process, the recovery rate of lithium ions is higher than 80%, the fresh water consumption of 1 ton of lithium chloride product is less than 50 cubic meters, the production cost is low, the chemical units are few, and the automation degree is high.

The secondary amide contained in the extraction system consists of a single compound or a mixture of two or more compounds, wherein R1 is selected from a C2˜C12 alkyl, or a C3˜C12 cycloalkyl containing a single-ring structure, R2 is selected from a C1˜C11 alkyl, or a C3˜C11 cycloalkyl containing a single-ring structure; the total number of carbon atoms in the molecule is 12˜18. With a volume ratio of an organic phase and a brine phase being 1˜10:1, at a brine density of 1.25˜1.38 g / cm3 and at a temperature of 0˜50° C., a single-stage or multi-stage countercurrent extraction and a stripping are conducted to obtain a water phase with a low magnesium-lithium ratio, which is subjected to concentration, impurity removal and preparation to get lithium chloride, lithium carbonate and lithium hydroxide respectively. Water is used for stripping, greatly reducing the consumption of acid and base, and the separation process is shortened.

The present invention discloses a method for reducing magnesium and aluminum impurities in wet-process phosphoric acid by using fluorine-containing tail gas from phosphorus chemical by-products, belonging to the field of wet-process phosphoric acid purification. This method is to send the fluorine-containing tail gas escaping from the wet-process phosphoric acid extraction reaction tank and / or the wet-process phosphoric acid concentration evaporator into the gas absorption reaction device after condensation and gas-liquid separation to carry out a multi-stage countercurrent absorption reaction with wet-process phosphoric acid, and after filtration, wet-process purified phosphoric acid with low magnesium and aluminum contents can be obtained. This method uses the fluorine-containing tail gas from phosphorus chemical by-products as raw materials, and after simple treatment, it can be used to reduce magnesium and aluminum impurities in wet-process phosphoric acid. It can not only make full use of the fluorine resources in the fluorine-containing tail gas from phosphorus chemical by-products, greatly reduce the cost of removing impurities in wet-process phosphoric acid, but also play the role of stripping and concentration, reduce the fluorine ion content in wet-process phosphoric acid and increase the acid concentration of wet-process phosphoric acid, which is easy to realize industrialization and has obvious economic benefits.

The invention discloses a method for increasing yield by adding magnesium oxide into calcined dolomite, which comprises the following steps: calcining dolomite to obtain calcined dolomite; adding exogenous magnesium oxide into the calcined dolomite according to the content of magnesium oxide in the dolomite to obtain optimized calcined dolomite; and the optimized calcined dolomite, silicon iron and fluorite are subjected to mixing, ball pressing and vacuum reduction, and the magnesium ingot is prepared. The technical problems that in the prior art, the magnesium content of dolomite is low, the quality is poor, the overall production cost is increased, the material-magnesium ratio is difficult to reduce, and silicon iron is wasted are effectively solved.

The invention provides a preparation method and application of a low-grade copper-nickel ore magnesium removal inhibitor, and belongs to the technical field of copper-nickel ore magnesium removal, and the preparation method comprises the following steps: mixing starch, ethylenediamine, methyl acrylate and maleic anhydride according to a preset mass ratio to form a mixed material; adjusting the pH value of the mixed material to a preset range to enable the mixed material to form a colloid precursor; adding an initiator into the treated colloid precursor to initiate a colloid polymerization reaction; raising the temperature of the initiated reaction system to a preset reaction temperature, and performing constant-temperature reaction for a preset time to form a reaction product with a colloid adsorption structure; and filtering and drying the reaction product in sequence to obtain the magnesium removal inhibitor with the capacity of targeted adsorption of magnesium minerals. According to the method, the efficiency and effect of the magnesium removal inhibitor are improved through targeted adsorption, then magnesium-containing minerals in the low-grade copper-nickel ore are effectively inhibited, and finally the copper-nickel ore with the low magnesium content is obtained.

This utility model discloses a magnesium material preheating and feeding device, which includes a horizontally placed preheating cylinder. A perforated feeding conveyor belt is transversely arranged inside the preheating cylinder. Multiple sets of radially extending movable frames are symmetrically arranged on both sides of the perforated feeding conveyor belt on the preheating cylinder. Heating rods are installed at the inner ends of the movable frames, and driving mechanisms are connected to the outer ends of the movable frames to drive them to move radially along the preheating cylinder. This magnesium material preheating and feeding device can preheat the magnesium material during the feeding and conveying process, avoiding excessive reactions caused by excessively low magnesium material temperatures during the feeding process, which would affect the processing effect.

The extraction system contains secondary amides and alkyl alcohols which are separately used as the extractants for extracting lithium and boron and consist of a single compound or a mixture of two or more compounds, and the total number of carbon atoms in their molecules are 12˜18 and 8˜20 respectively; the extraction system has a freezing point less than 0° C. With a volume ratio of an organic phase and a brine phase being 1˜10:1, at a brine density of 1.25˜1.38 g / cm3, at a brine pH value of 0˜7 and at a temperature of 0˜50° C., a single-stage or multi-stage countercurrent extraction and a stripping are conducted to obtain a water phase with a low magnesium-lithium ratio, which is subjected to concentration, impurity removal and preparation to get lithium chloride, lithium carbonate, lithium hydroxide and boric acid respectively. Water is used for stripping, greatly reducing the consumption of acid and base.

The invention discloses a blowing desulfurization method, and belongs to the technical field of metallurgy. In order to solve the problems of low desulfurization rate, low magnesium utilization rate and the like in the prior art, the invention provides a blowing desulfurization method which comprises the following steps: dispersing magnesium-aluminum alloy powder in an organic solvent, and adding a passivating agent to obtain passivated magnesium-aluminum alloy powder; and inserting the spray gun into a ladle, firstly spraying the passivated active lime and the aluminum powder, and then spraying the passivated magnesium-aluminum alloy powder to finish desulfurization. The magnesium-aluminum alloy powder is utilized to create in-situ desulfurization thermodynamic conditions, the magnesium vapor pressure is reduced, the retention time in the molten iron is prolonged, the sulfur content in the molten iron is reduced, the magnesium utilization rate is increased, the material adding conditions are controlled, the desulfurization effect is fully exerted, and the desulfurization effect is remarkably improved.

The invention relates to the technical field of magnesium oxide, and provides high-purity magnesium oxide and a preparation method thereof.The preparation method of the magnesium oxide comprises the following steps that S1, a dispersing agent is added into ammonia water to be mixed, and a mixture is obtained; s2, adding a magnesium chloride solution into the mixture for reaction to obtain magnesium hydroxide; and S3, treating the magnesium hydroxide with an amino compound, and calcining to obtain the high-purity magnesium oxide. According to the technical scheme, the problem of low magnesium oxide purity in related technologies is solved.

The application discloses a kind of boron magnesio-iron ore containing uranium magnesium extraction beneficiation methods, adopt multi-section closed circuit crushing classification, stage grinding gradient magnetic separation, strong magnetic weak magnetic combined impurity removal, targeted magnesium extraction combination process, first simultaneously realize the efficient recovery of iron, uranium valuable elements, then grade enrichment magnesium-containing minerals from iron tailings, finally through the targeted purification process of precipitation and high gradient magnetic separation impurity removal, dehydration, calcination preparation high-purity magnesium powder;The application has the advantages that: whole-process closed loop is efficient, realize the collaborative comprehensive recovery of iron, uranium, magnesium in boron magnesio-iron ore, and the problems of low magnesium recovery rate, insufficient product purity, complex process and high environmental pressure in the existing process are solved; No strong acid and strong alkali and other high-pollution reagents are used throughout the process, the equipment combination is compact, the process parameters are controllable, the energy consumption and production cost are low, it is suitable for industrial large-scale production, and the comprehensive utilization rate of boron magnesio-iron ore resources is improved.

The invention provides a method for improving magnesium ion conversion rate and enhancing magnesium hydroxide production efficiency, and relates to the technical field of magnesium hydroxide preparation. The method comprises the following steps: preparing the waste bischofite into a solution, adding solid sodium chloride or potassium chloride, carrying out a dissolution reaction, adding ammonia water after the pH and the conductivity of a reaction system are completely stable, ending the reaction when the pH and the conductivity of the reaction system are not increased any more, filtering to obtain magnesium hydroxide, collecting a mixed solution containing sodium and potassium, and concentrating for recycling. According to the method, the primary conversion rate of magnesium ions can be increased by 10% or above, and the production efficiency of magnesium hydroxide under the same condition can be increased by 15% or above. The method can solve the problem of low magnesium ion conversion rate in the production process of preparing magnesium hydroxide by a chemical method, reduces the energy consumption in the reaction process, improves the production efficiency of magnesium hydroxide, and has great economic value.