40results about How to "Simple crystallization process" patented technology

The invention relates to a method for separating out nafcillin acid crystal from a nafcillin sodium aqueous solution, which comprises the following steps: adding one of ethyl acetate, butyl acetate, n-butanol, n-hexane or petroleum ether as an extracting agent into the nafcillin sodium aqueous solution, and dripping an acidifying agent into the solution to make the pH value to be between 1.5 and 2.0 so as to separate out the crystal; and separating out the crystal, washing the crystal by purified water to make the pH value of washing liquor to be 4.0, drying the crystal at a temperature of between 45 and 55 DEG C to ensure that the moisture is below 3 percent to obtain the nafcillin acid crystal. The nafcillin acid crystal separated out by the extracting agent has the advantages of good crystal form, easy filtration, easy drying, less residual solvent in a product, and good quality; and the content of nafcillin acid is more than 93 percent. The crystallization method has the advantages of simple crystallize process, single extracting agent, and easy reclamation.

The invention provides a crystallization process of polycrystalline silicon and an ingot casting process of polycrystalline silicon. The crystallization process comprises the following steps: when a silicon material is in the state of coexistence of solid silicon and liquid silicon, the temperature of the top of an ingot furnace is kept so as to continuously melt solid silicon, and the temperature of the top in the ingot furnace is gradually lowered to enable the liquid silicon to be subjected to recrystallization to form the polycrystalline silicon ingot. The crystallization treatment is performed to the liquid silicon, when the silicon material is in the state of mixing of solid and liquid, so the temperatures of liquid silicon in all the ingot furnaces are basically the same, latent heat of the liquid silicon is the same, and therefore the crystallization velocity of the liquid silicon is enabled to be stable, the crystallization stability of liquid silicon is improved, and the properties of solar cells manufactured by the polycrystalline silicon ingot is improved. Meanwhile, the crystallization process of the polycrystalline silicon has the characteristics of simple process and high production efficiency.

The invention provides a tildipirosin 1,4-dioxane solvate and a preparation method thereof. Characteristic peaks occur in an X-ray powder diffraction pattern represented by 2theta when 2theta is equal to 6.06+ / -0.2, 8.42+ / -0.2, 9.34+ / -0.2, 9.94+ / -0.2, 10.28+ / -0.2, 12.34+ / -0.2, 13.44+ / -0.2, 13.74+ / -0.2, 14.66+ / -0.2, 15.58+ / -0.2, 15.78+ / -0.2, 16.40+ / -0.2, 17.00+ / -0.2, 17.90+ / -0.2, 18.60+ / -0.2, 19.32+ / -0.2, 20.10+ / -0.2, 21.40+ / -0.2, 22.34+ / -0.2, 22.68+ / -0.2, 23.34+ / -0.2 and 24.18+ / -0.2. The preparation method employs a constant-temperature suspended crystal transformation process and is simple in process and low in energy consumption. The tildipirosin 1,4-dioxane solvate is in a rod shape and crystal is of a regular shape.

The invention discloses a cefodizime sodium compound solid, a method for preparing the same and a pharmaceutical preparation of the cefodizime sodium compound solid, wherein the method for preparing the cefodizime sodium compound solid comprises the following steps of: first, dissolving crude cefodizime sodium salt in an acetone aqueous solution, then adding activated carbon to adsorb and filter, cooling the filtrate, stirring to separate the solid out, adding an acetone solvent to separate the solid out, filtering and drying, thus obtaining the cefodizime sodium compound solid. The prepared compound solids are fine particles, and have uniform particle size distribution and good liquidity, the crystallization technology is simple, the residual amount of organic solvent is low, and the product stability and pharmaceutical safety are effectively improved.

The present invention relates to a new crystal form I of pentostatin and its preparation method and use. The crystal form I has good solubility and is conducive to improving the intestinal absorption and oral bioavailability of the drug; the crystal form I of the present invention The medicine also has the advantages of high product purity, excellent physical and chemical properties, good chemical stability, and reproducible processing (filtration, drying, and tabletting); the crystallization process of the invention is simple, easy to operate, and less polluting, and can realize industrial production.