Remove the impurities contained in the particles
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Our company’s product is in the form of solid particles, and it is insoluble in any solvents. The reaction materials are two liquids, and after the reaction, certain of these raw materials remain trapped within the solid particles and are difficult to remove. Does anyone have a good method for this? The reaction is a substitution reaction between an alkane and excess bromine, and the particles contain free bromine!
Since they are both solids and do not dissolve, centrifugation can be used for separation. Extraction is unlikely to work, as both will dissolve in organic substances; if an inappropriate extractant is chosen, reactions may occur, which would only add to the complications!
The product referred to by the original poster is likely bromo**alkane. It is recommended that the poster investigate the fundamental differences in properties between this product and free bromine, such as solubility, melting and boiling points, as well as various chemical properties, before deciding on the method to be used for separation.
It’s better to try organic solvents; the product is polar, while free bromine is non-polar. Trying non-polar solvents should help find a solution.
Baking + purging and/or vacuuming?
The main issue is that the particles of the product contain trace amounts of ionized bromine; it is required that only organic bromine be present, with no free bromine allowed, and it should be contained within the product. I would like to ask if there are any good methods to remove it without using solvents
It seems the original poster didn’t explain clearly; free bromine generally refers to elemental bromine. In the case of organic reactions, the residue is most likely elemental bromine, while in the case of aqueous solutions, hydrogen bromide may remain as a residue. If it is elemental bromine/hydrobromic acid, the vapor pressure of bromine can be increased by heating through baking (bromine has a boiling point of only 58.5 degrees, and hydrobromic acid is gaseous at room temperature); the partial pressure of bromine in the gas phase can be reduced by purging with air, nitrogen, or CO2. This approach allows for a lower temperature while achieving the same separation effect, which is useful if the components are sensitive to heat, and it should make it possible to extract bromine. To improve permeability, pressure-variable breathing operation can be used to repeatedly replace the bromine within the particles. If it’s an inorganic bromide salt, things get more complicated. If possible, adjustments can be made to the raw materials to ensure that no inorganic bromide salts are formed. Supercritical extraction can also be considered; the most commonly used method is CO2 extraction, which leaves no harmful residues and does not require high temperatures. It is often used to extract various components (including those that are non-polar). Supercritical extraction can also be done using other substances. The key here is the selectivity of extraction. I don’t know the specific details, so I’m not sure whether it’s appropriate or not.
We are an organic bromide used as a flame retardant. The reason I ask this is that during the reaction process, it is very intense, and the product particles formed in an instant contain elemental bromine. What are some good solutions!
The main consideration when encapsulating something is the issue of diffusion; heating combined with changes in gas pressure might be useful. If that doesn’t work, reducing the pressure more significantly can produce a somewhat \"popcorn\" effect； Extraction might also be useful. If the product is too dense and impurities remain trapped inside, it can be tried to crush first; if granulation is needed later, further processing can be carried out. From a safety perspective, CO2 is the best choice for purging gas, followed by N2; air may present problems. You can only try this thing for now; it’s recommended that you start with low-cost methods. You can create a simple testing setup that doesn’t cost much – just a few bottles of gas, an adjustable heater, a thermometer, and that will be enough to try heating and purging first ； With another small pressure vessel and some accessories, one can try performing pressure variation operations ； Crushing can be done with a mortar by oneself. . . . The analysis was sent to someone else for completion. I’m supposed to place orders for the necessary raw materials and equipment right now.
Is purging done by continuously introducing carbon dioxide for circulation while reheating? Is variable-pressure breathing meant to alternate between positive and negative pressure, causing it to expand and contract? Isn’t it? I haven’t dealt with this before; please advise. Could you explain what the particle size of the product is in micrometers?
Blowing with hot air is the most suitable method. That heater heats the gas, allowing for good temperature control. Voltage transformation can involve increasing or decreasing pressure, as well as maintaining pressure at constant levels.