Can activated carbon filters remove chloride ions?

The main function of an activated carbon filter is to remove large molecular organic substances, iron oxides, and residual chlorine. This is because organic substances, residual chlorine, and iron oxides can easily poison ion exchange resins, while residual chlorine, cationic surfactants, and similar substances not only poison the resins but also damage the membrane structure, causing the reverse osmosis membrane to become ineffective. The adsorption principle of activated carbon is that a balanced surface concentration is formed on its particle surface, after which organic impurities are adsorbed into the interior of the activated carbon particles; the adsorption efficiency is very high at the beginning of use. However, over time, the adsorption capacity of activated carbon decreases to varying degrees, and as a result, its adsorption efficiency also declines. If the water quality in the aquarium is poor and the organic matter content is high, the activated carbon will quickly lose its filtering capacity. Therefore, activated carbon should be cleaned or replaced regularly. 　　The size of activated carbon particles also affects the adsorption capacity. Generally speaking, the smaller the activated carbon particles, the larger the filtration area. Therefore, powdered activated carbon has the largest total surface area and the best adsorption capacity, but it can easily flow into the aquarium with water, making it difficult to control, which is why it is rarely used. Granular activated carbon, due to its granular structure which makes it less prone to flowing, prevents impurities such as organic matter in water from clogging the activated carbon filter layer. It possesses strong adsorption capacity and is easy to handle and replace. 　　The adsorption capacity of activated carbon is proportional to the time it is in contact with water; the longer the contact time, the better the quality of the filtered water. Note: The filtered water should flow out of the filter layer slowly. The new activated carbon should be washed thoroughly before its first use; otherwise, ink-black water will flow out. Before installing the activated carbon in the filter, a layer of sponge 2–3 centimeters thick should be placed at the bottom and top; this serves to prevent large particles such as algae from penetrating inside. After 2–3 months of use, if the filtering efficiency declines, the activated carbon should be replaced, and the sponge layer also needs to be replaced regularly. 　　An activated carbon filter pressure vessel is a type of pressure vessel filled with a layer of coarse quartz sand and high-quality activated carbon. In water quality pretreatment systems, activated carbon filters can adsorb residual chlorine that cannot be removed by previous filtration stages, thereby preventing the subsequent reverse osmosis membranes from being oxidized and degraded. They also adsorb various polluting substances such as small molecular organic compounds that leak from earlier filtration stages. These filters have a significant effect on removing unpleasant odors, colloids, pigments, and heavy metal ions from water, and they can also help reduce COD levels. The SDI value of the RO feed water can be further reduced to ensure proper SDI levels

This post was last edited by piter_1984 on 2012-2-9 at 16:46. In the chemical industry, activated carbon is often used for removing chlorine from water. Here’s some information about it: Activated carbon is produced by high-temperature carbonization and activation of wood charcoal, coal, or fruit pits. Due to its porous solid structure, which contains interconnected capillaries, it has a very large surface area – up to 2000㎡ per gram of activated carbon. As a result, it has a strong adsorption capacity; it can not only remove free residual chlorine but also eliminate odors, color, and organic substances in water. The dechlorination effect of activated carbon is not merely a physical adsorption process; a series of chemical reactions also occur on its surface. When water containing free chlorine passes over the surface of activated carbon, hypochlorous acid is first adsorbed on that surface, after which it immediately decomposes into hydrogen chloride and atomic oxygen, as follows: HClO = HCl + O. Atomic oxygen rapidly changes from an adsorbed state to a bonded state with carbon atoms, as follows: C + O → CO↑, C + O → CO2. Therefore, there is no issue of adsorption saturation when using activated carbon for dechlorination; only a small amount of carbon is lost. As a result, activated carbon can be used for dechlorination for a considerable length of time. However, the adsorption capacity of activated carbon for deodorization, decolorization, or removing organic substances diminishes after being used for a certain period of time. It should be regenerated after running for a period of time. There are various regeneration methods; generally, the thermal regeneration method is used, in which the activated carbon is regenerated at high temperatures of 500–1000°C, causing the organic substances adsorbed on its surface to decompose into CO2 and water ； It can also be cleaned with high-pressure steam or regenerated with a NaOH solution. It should be noted, however, that chloride ions cannot be removed by activated carbon; only residual chlorine can be removed.

To put it directly: No. Activated carbon cannot remove chloride ions; for removing chloride ions, reverse osmosis or ion exchange methods are more suitable. However, through reaction, activated carbon can effectively reduce the level of active chlorine (oxidizing chlorine), but this process also damages its physical structure, thereby reducing its useful life.

First of all, it is necessary to understand that there is a fundamental difference between residual chlorine and chloride ions. In our RO systems, activated carbon is used to remove residual chlorine, and this is mainly due to the adsorption capacity of activated carbon, which allows it to absorb residual chlorine, organic substances, and impurities present in the water. It can only eliminate the oxidizing properties of these substances, but it does not replace the chloride ions, as ion exchange resins do; therefore, the chloride ions in the water should still be present. Personal opinion!

Activated carbon can be used to adsorb chloride ions. Activated carbon filtration is a form of physical adsorption filtration; it only manages to adsorb chloride ions within itself, and by backwashing the filter regularly, these chloride ions can be removed.

So do you know what the removal rate can reach?

Chloride ions cannot be removed using activated carbon; they can only be removed through desalination methods such as reverse osmosis and electroadsorption

Activated carbon filters cannot remove chloride ions; they can only absorb the oxidizing residual chlorine. In desalination processes that use reverse osmosis systems, activated carbon filters are necessary for pre-treatment, otherwise the reverse osmosis membranes will fail after a short time!

An activated carbon filtration pressure vessel is a type of pressure vessel filled with a layer of coarse quartz sand and high-quality activated carbon. 　 Activated carbon filters are primarily used in water supply and wastewater treatment systems to remove organic matter, color, and residual chlorine from water. 　　Function: In water quality pretreatment systems, activated carbon filters can absorb residual chlorine that cannot be removed by previous filtration stages, thereby preventing the reverse osmosis membranes in subsequent stages from being oxidized and degraded. They also capture various polluting substances such as small molecular organic compounds that leak from earlier filtration stages. These filters effectively remove unwanted odors, colloids, pigments, and heavy metal ions from water, and they also help to reduce COD levels. The SDI value of the RO feed water can be further reduced to ensure proper SDI levels

I have an excellent method for removing chloride ions from water or electrolytes – it’s simple and economical, with costs that are unbelievably low. If any factories or other businesses need to remove chloride ions, feel free to contact me. Let’s use QQ for contact first. QQ number: 75328760 Nickname: Dechlorination