6results about How to "Fine particle" patented technology

A method for recovering organic tin in a vinyl ether compound transesterification kettle liquid, comprising the following steps: 1) taking the vinyl ether compound transesterification kettle liquid, cooling to-10-40 DEG C, standing, until crystals are precipitated in the transesterification kettle liquid, filtering, or, cooling to-10-40 DEG C, adding 0.1-5% of organic tin powder in mass fraction to the transesterification kettle liquid, stirring and mixing uniformly, then standing, until crystals are precipitated in the transesterification kettle liquid, filtering; 2) adding a basic solution with a concentration of 5-8 wt% to the crystals obtained by filtering, in a mass ratio of 1:0.5-10, and heating to 25-60 DEG C, until flocculent substances appear on the surface of the basic solution, and filtering the lower aqueous phase; 3) washing the crystals obtained by filtering with water, then washing with an organic solvent, drying, to obtain organic tin. The process condition is mild and the operation is convenient, the recovered organic tin can be used repeatedly, the production cost of enterprises is reduced, and environmental pollution is avoided.

This invention relates to the field of sulfur production technology and discloses an oil-extended insoluble sulfur and its preparation method. The method includes: drying industrial sulfur with a sulfur content ≥99.9% and heating it to 135~145℃ to melt it; heating the molten sulfur to 230~250℃ under a pressure of 1.5~2.5MPa to carry out a polymerization reaction, adding a composite polymerization auxiliary during the polymerization reaction; depressurizing the molten sulfur after the polymerization reaction within 0.1~0.5s and injecting it into a quenching liquid for quenching to obtain crude insoluble sulfur; drying the crude insoluble sulfur and mixing it with iodine, then grinding and aging it to obtain an aged product; extracting the aged product with an extractant and drying it to obtain high-purity insoluble sulfur powder; and coating and extruding the high-purity insoluble sulfur powder with aromatic oil and a composite stabilizer. This invention simultaneously solves the contradiction between low conversion rate of the low-temperature method and poor safety of the high-temperature method, which has long plagued the industry, and achieves better technical results.

The invention discloses a preparation method of high-quality anhydrous sodium acetate. Comprising the following steps: dropwise adding alkali liquor into acetic acid or an acetic acid solution in a stirring state to obtain a sodium acetate solution, and preparing anhydrous sodium acetate from the sodium acetate solution by using a spray dryer. The sodium acetate solution is directly subjected to spray drying by using the spray dryer, the solution does not need to be concentrated, crystallized and dried, the operation steps are reduced, the process is simple, the yield is high, and the cost is low. The water content of the prepared sodium acetate powder is less than 1.0%, the sodium acetate content is greater than or equal to 99.0%, and the yield is greater than or equal to 98.5%.

This invention provides a flame retardant for water-based fire-retardant coatings for steel structures, prepared from the following raw materials: urea, phosphoric acid, acidic lignin, and pentaerythritol; the weight ratio of urea, phosphoric acid, acidic lignin, and pentaerythritol is 1:(0.8-1):(0.1-0.5):(0.01-0.05). Applying this flame retardant to water-based fire-retardant coatings for steel structures achieves both moisture resistance and flame retardancy.

The application discloses a semiconductor device and a process cavity maintenance method. The maintenance method comprises the following steps: providing a process cavity, a target film layer is deposited on the inner wall of the process cavity, and the target film layer is a semi-insulating oxygen-doped polysilicon film layer; a first gas is introduced into the process cavity, the target film layer is subjected to a first treatment, the target film layer is oxidized to form an oxidized target film layer, and the oxidized target film layer is cracked and peeled off under the action of stress, and the first gas is an oxidizing gas; and a second gas is introduced into the process cavity, and the process cavity is purged. The application can realize online maintenance of the process cavity, maintain the particle performance at a good level, has the advantages of simpler, more reliable, more efficient and faster maintenance, and can greatly reduce the labor cost and the material cost.

The re-humidification and atomization system of the re-humidification zone of the tobacco sheet re-drying machine of this utility model includes: a re-humidification zone 1, a re-humidification zone 2, a re-humidification zone 3, a main conveyor belt, a first water tank, a second water tank, a first water pump, and a second water pump. The re-humidification zones 1, 2, and 3 are placed sequentially. The main conveyor belt passes through the main housing of the re-humidification zones 1, 2, and 3 sequentially. The high-temperature condensate recovery pipe is connected to the first water tank through a first automatic switch valve. Hot water and cold water are mixed in the second water tank and then sent to the re-humidification zones 1, 2, and 3 through the main re-humidification humidification pipe and the second pump humidification branch pipe. In the second water tank, the water tank is divided into upper and lower parts by a partition. The cold water pipe enters the upper part of the partition, and a mixing water pipe is set below the partition. Cold water enters the mixing water pipe from the cold water pipe, and hot water from the first water tank extends into the mixing water pipe of the second water tank. Small water outlet holes are evenly distributed in the part of the hot water pipe in the mixing water pipe.