摘要:
Bromine containing compounds, such as calcium bromide, sodium bromide and the like, are prepared in high purity and more quickly with less waste by using a process with two bromination stages and often a third step wherein the crude product mixture can be adjusted to meet specific product requirements. In the first bromination stage, the majority, but not all, of a substrate is brominated using a reductive bromination reaction, the remaining unreacted substrate is converted to product in the second stage through another a reductive bromination reaction, although the specific reagents may be different, wherein the addition of bromine and a reducing agent are carefully monitored.
摘要:
A method of reacting amine compounds with halons and perhalogenated compounds, resulting in the conversion of these ozone-depleting species into non-volatile salts and a variety of other amine derivatives is disclosed.
摘要:
Metal bromides, and particularly alkali and alkaline earth metal bromides, are prepared from a basic metal compound and bromine in the presence of added formaldehyde as a reducing agent.
摘要:
Large ultra-pure, prism-quality essentially single crystal boules and ingots of alkali metal chlorides and alkali metal bromides are grown by the methods of Kyropoulos and Stockbarger. Optically single crystals of these alkali metal halides are clear optical bodies free of haze throughout. A typical Kyropoulos grown boule of KBr of this invention is also absorption-free, and has cleavage or crystallographic planes which deviate from parallel by 1.degree. to 3.degree. per inch. By `absorption-free` is meant freedom of absorption at 7.2 microns (.mu.) due to nitrate, at 9.5-11 .mu. due to silicate, and at between 8 and 9 .mu. due to sulfate, which are the most difficult to control but as the term implies the bodies are also free of infrared absorption for impurities such as CO.sub.3.sup.-2, PO.sub.4.sup.-3, OH.sup.-, BO.sub.2.sup.-, SH.sup.-, CNO.sup.-, HCO.sub.3.sup.-, etc., which are easily avoided by use of good commercially available growth stock.A particular process for growth for either of the foregoing methods in a silica or quartz crucible, comprises growing an ultrapure ingot of KBr from a relatively impure melt containing silicate, sulfate, nitrate and nitrite ions, and includes maintaining the sodium content of the melt during growth to less than about 20 ppm (parts per million) and the barium content less than 10 ppm, adding barium bromide to the melt if necessary, and, contacting the melt with a trace of free bromine in a covered, but not air-tight, pot.
摘要:
The invention belongs to the field of bromine recovery from waste circuit board, and particularly relates to a method for recovering high-purity sodium bromide from bromine-containing crude salt. The invention mainly includes the steps of acidification oxidation, multi-stage extraction, and cooperative back extraction. Compared with traditional chlorine oxidation and single urea back extraction technology, the acidification oxidation process can be effectively controlled by reasonable adjustment of the added amount of hydrochloric acid and sodium chlorate, and the tail gas can be absorbed and reused to avoid secondary pollution and resource waste. At the same time, urea is used with sodium carbonate for cooperative back extraction to achieve a high back extraction rate which greatly reduces the amount of urea, and obtains high-purity sodium bromide crystals. The efficient recovery of bromine resources in bromine-containing crude salt is realised. The benefits of the invention are: high product purity, simple operation, environmental friendliness.
摘要:
Provided are a liquid preparation wherein the pharmaceutically active ingredient is stabilized, and a stabilizing method therefor. A liquid preparation comprising a pharmaceutically active ingredient having a primary or secondary amino group (wherein the amino group does not constitute a part of the amide structure), an organic acid and a salt, which is substantially free of a reaction product of the pharmaceutically active ingredient and the organic acid.
摘要:
A method for degrading Rhodamine B including: mixing BiOBr and Rhodamine B; and irradiating the mixture with a radiation having a wavelength of from 440 nm to 554 nm. The Rhodamine B may be in an aqueous solution. The BiOBr may be added to the aqueous solution of Rhodamine B in an amount of from 0.2 to 0.5 mg/ml. The BiOBr may have a sheet-like structure with particles having a diameter of from 3 μm to 5 μm. The BiOBr may be in a pure crystal tetragonal phase.
摘要:
This invention relates to a process for reducing metal halates to metal halides, the process comprising reacting a metal halate with a reducing agent in an aqueous alkaline reaction medium having a pH above about 7, wherein the amount of reducing agent is sufficient to reduce substantially all of the metal halate to metal halide.