61 results about "Magnesium oxalate" patented technology

The invention discloses a non-woven cloth suspension filler which is prepared by the following constituents in parts by weight with the conventional method: 40-50 parts of polyethylene, 25-35 parts of polypropylene, 6-10 parts of carbon black, 3-7 parts of ferric oxalate, 4-6 parts of magnesium oxalate and 1-2 parts of antioxidant. The specific gravity of the non-woven cloth suspension filler is closed to that of water. No fixing support is required. The filler can suspend in the water in a pool with aeration stirring and is uniformly fluidized in the whole pool. The energy consumption is low, and the non-woven cloth suspension filler has a good prospect.

The invention discloses a method for preparing high-purity magnesium oxalate and lithium carbonate from salt lake brine of high magnesium-lithium ratio. The method comprises the following steps: 1) filtering the salt lake brine to remove suspended matters and solid impurities; 2) adding oxalic acid into the filtered salt lake brine; carrying out reaction for 30 to 180 min under the conditions that the temperature is 20 to 60 DEG C, the pH is 3 to 5, and the stirring speed is 150 to 500 rpm, so as to obtain brine of low magnesium-lithium ratio and magnesium oxalate precipitate; washing the magnesium oxalate precipitate with 40 to 60 DEG C hot water for 3 to 5 times; drying the washed magnesium oxalate precipitate at 80 to 102 DEG C for 60 to 120 min to obtain the high-purity magnesium oxalate of which the purity is larger than or equal to 98%; 3) adding an impurity removing agent into the brine of low magnesium-lithium ratio, so as to obtain refined brine; adding sodium carbonate into the refined brine to obtain lithium carbonate crystal; filtering the lithium carbonate crystal; carrying out washing and drying to obtain lithium carbonate. The magnesium oxalate prepared according to the method is high in purity.

The invention relates to a method for recycling electrolytic manganese metal anode waste liquor. The method for recycling the electrolytic manganese metal anode waste liquor is characterized by sequentially comprising the following recycling steps: (1) after filtering anode waste liquor, adding ammonia water to regulate the pH value to be neutral; (2) adding NH4HCO and reacting; (3) carrying out filter pressing, so as to obtain an ammonium sulphate solution and manganese carbonate slag; washing a manganese carbonate slag phase to obtain manganese carbonate; (4) regulating the pH value of clear liquid, namely the ammonium sulphate solution, obtained after filter pressing, adding oxalic acid, and reacting; (5) carrying out the filter pressing, so as to obtain magnesium oxalate slag and ammonium sulphate filter liquor; washing the magnesium oxalate slag, so as to obtain magnesium oxalate. By adopting the method for recycling the electrolytic manganese metal anode waste liquor, manganese, magnesium and ammonium in the anode waste liquor are recycled, the problems existing in a long-term anode liquor recycling process are solved, abnormal phenomena in production are reduced, an electrolyte crystallization phenomenon is overcome, the yield is increased, the quality is improved, and the production cost is reduced.

The invention discloses a method for recovering manganese and magnesium from complex salt crystals generated in the manganese electrolysis process, which is characterized by recovering manganese and magnesium from complex salt crystals in the mode of preparing manganese dioxide and magnesium oxalate. The method comprises the following steps: totally dissolving the complex salt crystals by hot water to obtain a solution containing manganese sulfate and magnesium sulfate; filtering the solution, and adding an oxidant ammonium persulfate in the obtained filtrate to prepare manganese dioxide; continuously filtering the solution, adding a precipitator oxalate dehydrate into the obtained filtrate to prepare magnesium oxalate; and then, filtering again to obtain a filtrate containing ammonium sulfate and the like, wherein the filtrate can be reused when electrolytic manganese is produced. The manganese dioxide and the magnesium oxalate obtained with the method are pure and can be directly used as other raw materials for industrial production. The method has the characteristics of small investment, low cost and simple technology and is easy to operate, and the recovery rates of manganese and magnesium are respectively 97.9% and 98.7%.

This invention provides a method for preparing MgO with ultra-large specific surface area. The method comprises: (1) reacting between magnesium acetate and oxalic acid solution to obtain magnesium oxalate; (2) torrefying at a high temperature to obtain MgO with a specific surface area larger than 400 sq m/g. The method has such advantages as inexpensive raw materials, easy operation and high product quality.

The invention discloses a magnesium binding agent for cement-free castable and a preparation method thereof. The preparation method comprises the following steps: baking a magnesium raw material containing crystal water at a high temperature to remove the crystal water, and then grinding and sieving to obtain the magnesium binding agent, wherein the magnesium raw material can be any one of magnesium citrate, magnesium oxalate, magnesium gluconate and the like, the high temperature is 100-400 DEG C, and the baking time is 1-200 hours. The magnesium binding agent can form a net-shaped structureand has coagulation performance when being added with water and stirred, a refractory castable prepared from the magnesium binding agent has excellent normal-temperature mechanical performance, and spinel generated in situ at high temperature can improve the erosion resistance and thermal shock resistance of the castable; the binding agent has the advantages of no environmental pollution, simple production process, low production energy consumption and the like, is wide in application range, and is suitable for high-alumina, corundum, silicon carbide and other cement-free castables.

The invention relates to a method for preparing spectrally pure magnesium oxide. The preparation method comprises the following steps of: reacting metal magnesium powder with nitric acid, namely putting the magnesium powder into a small white porcelain pot, dripping high-purity diluted nitric acid into the pot, then adding H2O2 into the pot, and filtering the mixture to obtain filtrate A so as toobtain magnesium nitrate; and preparing saturated solution from high-purity oxalic acid, slowly adding the oxalic acid solution into the filtrate A to generate a large amount of white sediment, and heating and cooling the sediment to separate out the spectrally pure magnesium oxide. According to the preparation method, the metal magnesium powder is reacted with the nitric acid to prepare the magnesium nitrate, the prepared magnesium nitrate is reacted with the high-strength oxalic acid to generate magnesium oxalate, and the magnesium oxalate is dried at a high temperature to form the spectrally pure magnesium oxide. The preparation method has the advantages of simple processes, easy control of operation steps, advanced technology and high production efficiency; and the prepared spectrallypure magnesium oxide product has high purity and low impurity content, and the prepared magnesium oxide meets the requirement of high-end technology of the electronic industry.

The invention discloses polyacrylic ester polymer cement-based waterproof paint and a preparation method thereof. The paint is prepared from the following ingredients in parts by weight: 100 parts oftricalcium silicate cement, 40 to 60 parts of tetra-calcium aluminoferrite cement, 70 to 110 parts of polyacrylic ester emulsion, 60 to 80 parts of quartz sand, 5 to 15 parts of polysiloxane, 1 to 5 parts of silane coupling agents, 10 to 20 parts of silicon nitride and 10 to 16 parts of magnesium oxalate. The preparation method comprises the following steps of mixing the tricalcium silicate cement, the tetra-calcium aluminoferrite cement, the quartz sand, the silicon nitride and the silicon carbide; dispersing the mixture into the polyacrylic ester emulsion; heating the materials to 85 DEG C;then, adding the polysiloxane and silane coupling agents; performing stirring reaction; when the quantity of Si-C, Si-O-C, Si-C-N and Si-O-Si in the reaction system is unchanged, and after the cooling, adding the magnesium oxalate; performing homogeneous treatment. The produced polyacrylic ester polymer cement-based waterproof paint can be fast cured and coagulated; the space structure is compact;excellent mechanical property and waterproof and acid-alkali resistant performance are realized.

The invention relates to a preparation method of an MgO-modified silicoaluminophosphate fluidized bed catalyst. According to the preparation method, the problem that ethylene and propylene are low in selectivity in the process for preparing low carbon olefin from methanol by virtue of the catalyst in the prior art is solved. The preparation method comprises the following steps: (a) uniformly mixing a molecular sieve, a binding agent, a matrix material, magnesium oxalate, a surfactant and a liquid medium to form suspension liquid; (b) shearing the suspension liquid at high speed until the sizes of 90% of particles in the suspension liquid are smaller than 8 microns; (c) drying the suspension liquid to form a microsphere catalyst; and (d) roasting the microsphere catalyst at high temperature to form a finished catalyst, wherein a magnesium oxalate precursor with the specific surface larger than 200 m<2>/gMgO can be obtained by virtue of roasting at 50 DEG C in the step (a). According to the technical scheme, the problem is well solved. The preparation method can be applied to the industrial production for preparing a low carbon olefin catalyst from a methanol or dimethyl ether raw material.

The invention discloses a water culture nutrient solution for tea trees and relates to the technical field of water culture of tea trees. The water culture nutrient solution is characterized by comprising the following components: 500-800mg of calcium hydrogen nitrate, 400-500mg of potassium nitrate, 75-82mg of ammonium sulfate, 100-150mg of potassium dihydrogen phosphate, 200-300mg of magnesium oxalate, 2.2ml of iron salt solution, 4-4.5 ml of trace element liquid and 1L of distilled water. The water culture nutrient solution disclosed by the invention has the advantages of bright and robust branches and leaves, healthy plants, good culture effect and strong stress resistance of plants.

The present invention relates to composite mineral salt of potassium-magnesium hydrogen citrate and its preparation process. The potassium-magnesium hydrogen citrate is prepared through mixing citric acid and water, and reaction with potassium compound and magnesium compound at the temperature below 100 deg.c with the molar ratio between Mg, K, H and citric acid being 1 to 3 to 1 to 2. The composite salt of potassium-magnesium hydrogen citrate has obvious curative effect on urinary calculus, owing to the citrate radical ion and magnesium ion to suppress calcium-containing calculus crystallization, magenesium ion to lower the concentration of calculus forming matter in urine and capable of combining with oxalic acid to form magnesium oxalate to exhaust together with urine. The composite salt can raise pH value of urine and dissolve uric acid calculus and cystine calculus directly without causing adverse reaction.

The invention relates to a microporous magnesium-chromium spinel raw material and a preparation method thereof. According to the technical scheme, the preparation method comprises the following steps: adding magnesium oxalate and chromium carbide into a ball mill in a mass ratio of (1.1-1.15) to 1, and carrying out ball milling until the particle sizes are less than or equal to 100 microns, so as to obtain ball-milled powder; putting the ball-milled powder into a drying oven, and maintaining the temperature at 200-250 DEG C for 30-40 minutes, so as to obtain thermally processed powder; adding water which accounts for 15wt%-20wt% of the thermally processed powder into the thermally processed powder, carrying out wet milling in the ball mill until the particle size is less than or equal to 60 microns, so as to obtain a wet-milled material; and adding the wet-milled material into a mud refining machine, carrying out vacuum mud extrusion molding, and standing for 24-36 hours; putting the processed material into a muffle furnace, maintaining the temperature at 1550-1600 DEG C in an air atmosphere for 3-4 hours, carrying out furnace cooling, and crushing, so as to obtain the microporous magnesium-chromium spinel raw material. The preparation method is simple and low in production cost; the prepared microporous magnesium-chromium spinel raw material is good in sintering performance, high in spinel conversion rate and low in heat conductivity coefficient.

The invention discloses a method for processing sols of alumina refractory particles, which mainly aims to solve the problem of agglomeration of nano-powder during use in the prior art. The method comprises the following steps of: preparing magnalium precursor sols with a molar concentration of 0.5 to 2M from aluminium nitrate serving as an aluminum source, and magnesium oxalate or gnesium citrate serving as a magnesium source according to a mole ratio of Al to Mg of 2; putting the particles of aggregate particles of the alumina refractory material into an anti-acid container, and then pouring the magnalium precursor sols with a molar concentration of 0.5 to 2M into the container to soak for 5 to 10 minutes; after filtering the obtained objects by using a screen, putting the obtained particles into a sagger, and then carrying out thermal treatment on the obtained particles at the temperature of between 600 and 1,200 DEG C for 1 to 6 hours, and reacting the aluminosilicate refractory particles to synthesize nano magnesia-alumina spinel powder, and then obtain the aluminosilicate refractory particles attached with the nano magnesia-alumina spinel powder. The method of the invention has the advantage of uniformly-distributed nano-particles in the alumina refractory material can be used for processing refractory raw materials and improves the sintering process of the refractory raw materials.

The invention discloses a preparation method of a supported ruthenium-based catalyst, and belongs to the field of catalyst preparation. The method comprises the following steps of: taking magnesium oxalate as a carrier precursor, and preparing the supported ruthenium-based catalyst by adopting a precipitation deposition method. The supported ruthenium-based catalyst comprises a carrier and an active component, wherein the carrier comprises magnesium oxide, and the active component comprises Ru. The catalyst can be used as an ammonia decomposition hydrogen production catalyst. The supported ruthenium-based catalyst obtained according to the method has a low content of precious metal ruthenium, and has high catalytic activity and catalytic stability at a relatively low temperature. In addition, the method is simple in preparation process, low in cost and easy to realize large-scale production.

The invention relates to a magnesium olivine-texture lightweight refractory and a preparation method thereof. According to the technical scheme, the preparation method comprises the following steps: blending a DDBAC foaming agent, polyacrylamide, ammonium hydrogen carbonate and water in a mass ratio of 1 to (1-4) to (2-5) to (50-60), and carrying out ultrasonic dispersion in a container under a water bath condition, so as to prepare foaming liquid; blending nature magnesium olivine ore and silicon carbide in a mass ratio of 100 to (4-7), carrying out ball-milling, mixing in a planetary ball mill, and carrying out compression molding; carrying out thermal treating at 900-1000 DEG C in a muffle furnace, carrying out furnace cooling, crushing, and grinding, so as to obtain a thermally treated material; and blending the foaming liquid, the thermally treated material and magnesium oxalate in a mass ratio of (30-40) to 100 to (6-8), mixing, forming, carrying out vacuum freeze drying, and sintering at 1400-1500 DEG C in the muffle furnace, so as to obtain the magnesium olivine-texture lightweight refractory. The preparation method has the characteristics of low cost and high yield; and the prepared magnesium olivine-texture lightweight refractory has low volume density, large compression strength and small heat conductivity coefficient.