54 results about "Calcium magnesium carbonate" patented technology

An aqueous coating composition having a PVC of from 78 to 88% comprising, based on the total volume solids of the dry coating unless otherwise stated:a) opacifying pigment particles comprisingi) from 3 to 10% titanium dioxide,ii) from 0 to 20% of hollow polymeric particles;b) non-opacifying extender particles comprisingi) calcium magnesium carbonate, and / orii) calcium carbonate, and / oriii) nepheline syenite, and / oriv) kaolin,wherein i)+ii)+iii)+iv)=40 to 80%, and iv) is 0 to 20%;c) polymer binder particles of calculated Fox Tg of from 25 to 70° C. having an acid value of from 15 to 65 mg KOH / g of polymer and wherein the polymer particles are derived from acrylic monomers and optionally further comprising styrene and / or its derivatives;d) dispersant having a weight average molecular weight of at least 3500 Daltons;e) fugitive coalescing solvent;wherein the composition is free of non-fugitive coalescing solvent.

The invention provides a method for separating calcium and magnesium and preparing magnesium hydroxide by water dissolving and leaching of burnt dolomite. The method comprises the following operation steps: crushing the dolomite and burning into dolomite ashes; slaking the dolomite ashes by water to generate calcium hydroxide and magnesium hydroxide; filtering and separating an insoluble substance magnesium hydroxide; introducing carbon dioxide to leaching liquid to separate out calcium carbonate precipitate; separating again to obtain a calcium carbonate product, adding a purifying agent to filter residue to remove impurities such as iron, aluminum and the like, centrifuging and separating, and baking, so as to obtain the magnesium hydroxide product. The method has the characteristics of being low in cost, simple in process, and good in product quality, and a new production way is provided for preparation of magnesium hydroxide from dolomite.

Aqueous coating composition having a PVC from 78 to 85% and free of non-fugitive coalescing solvent, comprising, based on the total volume solids of the dry coating unless otherwise stated,a) opacifying pigment particles comprising from 3 to 10% titanium dioxide and from 0 to 20% of hollow polymeric particles;b) non-opacifying extender particles comprising calcium magnesium carbonate and / or calcium carbonate and / or nepheline syenite and / or kaolin;c) polymer binder particles of calculated Fox Tg of from 5 to 25° C. having an acid value of from 15 to 65 mg KOH / g of polymer;d) dispersant having weight average molecular weight of at least 3500 Daltons, and wherein the dispersant demand of a mixture of the opacifying pigment particles, other than the hollow polymeric particles, of a) and the extender particles of b) is greater than 0.35 wt %, calculated on the weight of the titanium dioxide and extender particles;e) fugitive coalescing solvent.

The invention discloses a method for preparing calcium-magnesium carbonate mineral Cal-xMgxCO3 at a high temperature under high pressure. The method includes evenly grinding and mixing analytically-pure calcium carbonate, magnesium oxalate powder and anhydrous oxalic acid to obtain a mixture serving as an initial raw material, pressing the mixture into a cylinder by a tablet machine, inserting a cylindrical sample into a platinum tube, sealing two ends of the platinum tube by a welding gun, putting the sample sealed by platinum in an h-BN tube by taking h-BN as a pressure transfer medium, assembling the sample in the h-BN tube in a high-pressure combined assembly block, putting the high-pressure combined assembly block in a cubic press for high-temperature high-pressure reaction, taking out the reacted sample, opening the platinum tube by a diamond cutter, and naturally air-drying the sample to obtain calcium-magnesium carbonate minerals. By the method, the technical problems such as operation process complexity, long reaction time, and low purity, low chemical stability and proneness to water absorption of obtained samples in existing calcium-magnesium carbonate mineral preparation methods are solved.

A flame retardant film comprising a polyester-containing film, the polyester-containing film comprising a flame retardant layer on a side thereof. The flame retardant layer includes a colloidal metal oxide in an amount of 6 g / m or more, an inorganic binder in an amount of 2 g / m or more, the first flame retardant being a phosphorus-containing compound in an amount of 10 g / m or more, and the second flame retardant being a phosphorus-containing compound in an amount of 10 g / m or more. And the second flame retardant is an inorganic compound selected from the group consisting of aluminum hydroxide, aluminum trihydrate, magnesium hydroxide, calcium magnesium carbonate, magnesium carbonate hydrate, alumina hydroxide, a boron compound, antimony trioxide, and combinations thereof in an amount of 6 g / m or more.