How to Eliminate Bromate How to Remove Bromate

Internationally recognized as a potential carcinogen of Class 2b, bromate is a by-product of ozone disinfection of natural water sources such as mineral or mountain springs. Internationally, the World Health Organization and the U.S. Environmental Protection Agency (EPA) stipulate that the maximum allowable concentration of bromate in drinking water is within the limit. Since bromate is a by-product of ozone sterilization, ozone is recognized as the most effective disinfection method, and what technology to use to replace ozone sterilization has become a problem.

Until a more effective sterilization method than ozone is found, a method that can selectively decompose bromate carcinogens in natural mineral water without affecting the sterilization effect of reserved ozone will be the best choice.

The conventional production process of drinking natural mineral water includes pumping pressure, ozone sterilization, storage and transportation, secondary ozone addition and final bottling. In addition to many organic and inorganic substances in natural raw water, there are also bromides in the order of ppb. When ozone is added for the first time, bromides react with ozone to convert bromate (bromate (bro3-), which can generally reach the order of 10 to 20 ppb, and is bottled in water after the second ozone addition.

The second addition of ozone before bottling (in the order of approx. 100 ppb) is to ensure that there is a certain amount of ozone residue in the bottled water and to sterilize both the water and the cap, which is critical in the bottling process. Among the existing ultraviolet light technologies, the use of low-pressure, medium-pressure or high-pressure mercury lamp ultraviolet light can moderately decompose bromate, but at the same time, it also decomposes the ozone reserved before bottling more strongly, because ozone decomposes most strongly at the ultraviolet wavelength of 230-270 nm, while bromate decomposes moderately at 200-250 nm. The absorption spectra of bromate and ozone were investigated, and it was found that the most suitable ultraviolet wavelength should be in the range of 200-230 nm, which not only ensured the full decomposition of bromate but also did not affect the reserved ozone.

The UV light source has a wavelength of 200-230 nm, and the test results show that the remover can selectively and efficiently decompose bromate in natural mineral water without affecting the reserved ozone, and the bromate decomposition products will not react with each other to regenerate bromate.

Bromide is added to react under acidic conditions to form bromine.

Extracted with carbon tetrachloride.

The excess bromide is precipitated with silver salts.

How did it come out again. This question.

Silver salts are added to form silver bromide precipitates and removed.

<>1. Dilute sodium hydroxide is used in the pre-base section.

The solution is washed and burned to remove bromine.

2. Then pass through the separating funnel.

Perform a split-pulse sock solution operation to remove sodium bromide.

3. Bromobenzene. The reaction with sodium hydroxide solution is very slow, so after the sodium hydroxide solution is added to bromobenzene and shaken, the bromine reacts to the inorganic layer, and the bromobenzene is in the organic layer, and then the liquid can be separated.

<>1. Wash with dilute bond sodium hydroxide solution to remove bromine.

2. Then socks Hongqiao will carry out the dispensing operation through the separating funnel to remove the sodium bromide.

3. The reaction between bromobenzene and sodium hydroxide solution is very slow, so after the sodium hydroxide solution is added to the bromoabsolute benzene and shaken, the bromine reacts to the inorganic layer, and the bromobenzene is in the organic layer, and then the liquid can be separated.

Ultraviolet technology.

The remover is equipped with a new ultraviolet light source, which can selectively and efficiently decompose bromate in natural mineral water, while not affecting the reserved ozone sterilization effect, the treatment is not affected by the pH value, and there is no need to add carbon dioxide gas to reduce the pH value of the mineral water, do not change the taste quality of the mineral water, and do not need to use activated carbon.

The lamp has a long service life and does not have the waste** disposal problems that come with traditional mercury UV lamps. The light source can be turned on and off instantly, and it only needs to be installed before the mineral water filling process, and it is easy to integrate into the existing natural mineral water production line, which is easy to install and has good replaceability.

In ultraviolet technology, the use of low-pressure, medium-pressure or high-pressure mercury lamp ultraviolet light can moderately decompose bromate, but at the same time, it also more strongly decomposes the ozone reserved before bottling, ozone decomposes most strongly at the ultraviolet wavelength of 230-270nm, and bromate decomposes moderately at 200-250nm.

1. Install an electrodialysis device to remove part of the bromide in the water; At the same time, when selecting the source water, the water with low bromide concentration should be selected as the water source for the production of mineral water.

3. It can reduce the pH of process water, thereby hindering the oxidation of bromide into bromate by oxygen.

4. After selecting the water source, during processing, you can remove part of the bromide in the source water by adding certain equipment, such as using electrodialysis devices.

Because the oxidation of chlorine is relatively strong, bromide ions can be oxidized to bromine element, liquid bromine and water will have stratification phenomenon, therefore, soluble bromide aqueous solution can be used for treatment, bromine in water will undergo disproportionation reaction, loss of yield, so the bromide solution should be saturated, so that the reaction is weakened, in summary, remove a small amount of chlorine in liquid bromine, specific method:

1. Take a clean beaker, add excess sodium bromide, add distilled water and stir to prepare a saturated sodium bromide solution.

2. Take a clean separating funnel, fix it on the iron frame, and inject sodium bromide solution (note: the piston of the funnel should be closed at this time).

3. With the help of a glass funnel, carefully inject liquid bromine into the separating funnel, plug the plug, and wear gloves.

4. Remove the separating funnel and quickly separate the funnel for 3-5 minutes to fully react the chlorine gas dissolved in the liquid bromine.

5. Liquid separation, liquid bromine is released from the bottom mouth to obtain pure liquid bromine, and sodium bromide solution is poured out from the upper mouth, which can continue to be used to treat other liquid bromine dissolved with chlorine gas.

A sufficient amount of chlorine gas is introduced and then fractionated with carbon tetrachloride.