In water treatment processes, multiple options exist to remove organic matter, suspended solids, bacteria, metals, and other elements.
Special attention must be paid to arsenic removal, as inefficient elimination will lead to health problems.
Does boiling water remove arsenic? No. Boiling water does not remove arsenic. In fact, it can increase its concentration. This is because part of the water evaporates, but the arsenic (which is a chemical element and not a germ) remains, concentrating in the remaining liquid.
Does chlorine remove arsenic? No. One should not attempt to remove arsenic using chlorine or other disinfectants. Arsenic is a chemical substance and cannot be “killed” like a bacteria or a virus, so adding chlorine does not make the water safe to drink with respect to this contaminant.
Do standard pitcher or activated carbon filters work? Generally not. You should not rely on the activated carbon filters typically found in household water pitchers or refrigerators, as these usually do not remove arsenic.
There are various methods that are effective for arsenic removal, such as reverse osmosis, electrocoagulation, or distillation for its removal. However, these technologies require high energy demand and specialized infrastructure, representing additional costs. Furthermore, hazardous liquid waste is generated.
The solution that offers the greatest number of advantages for removing arsenic from water is GEH, the easy-to-use filter medium adaptable to the existing conditions of industries.
Comparing methods for arsenic removal
Nanofiltration and Reverse Osmosis Membranes
| Pros | Cons |
| ✅ Proven technology | ❌ Non-selective (also removes desirable minerals) |
| ✅ Modular and scalable design | ❌ Requires pretreatment |
| ✅ High arsenic rejection efficiency | ❌ Generates concentrated reject stream |
| ❌ High energy consumption | |
| ❌ High investment and specialized maintenance |
Nanofiltration and reverse osmosis membrane methods are well-proven, modular, and scalable technologies that offer high arsenic removal efficiency.
However, their main disadvantage is their lack of selectivity: they remove virtually everything present in the water.
This results in highly concentrated reject streams, high energy consumption, and the need for specialized investment and maintenance.
Furthermore, to produce the required amount of treated water, 40-50% more feed water is required.
Therefore, this technology can be counterproductive when contaminants are present in very low concentrations, for example, on the order of 100 times lower in proportion, which are the only parameters outside the permitted limits.
In cases where arsenic is slightly above the permitted limit, implementing membrane technology would be impractical.
Arsenic removal by iron and manganese
| Pros | Cons |
| ✅ Simultaneous arsenic removal without additional processing | ❌ Efficiency depends on Fe/As ratio |
| ✅ Standard technology for groundwater applications | ❌ Does not guarantee compliance with regulatory limits |
| ❌ May require an additional polishing stage |
Iron and manganese removal is generally common in traditional well water. However, its effectiveness depends largely on the iron-to-arsenic ratio present in the water.
In some cases, this method does not guarantee compliance with regulatory limits, so an additional final polishing stage may be required.
In this context, for example, GEH treatment could represent one of the most suitable options for achieving the removal of these contaminants.
Flocculation with iron and aluminum
| Pros | Cons |
| ✅ Widely proven conventional technology | ❌ Generates sludge with arsenic (handling and disposal) |
| ✅ Simultaneously removes turbidity and other contaminants | ❌ Requires infrastructure (mixing, sedimentation, filtration) |
| ✅ Relatively low chemical cost | ❌ Greater operational complexity |
| ❌ Not ideal for small plants |
While flocculation uses proven technologies, requires relatively low chemical concentrations, and also removes turbidity and other contaminants, it creates a fundamental problem: it generates sludge containing arsenic, which must then be disposed of properly.
This represents an underlying problem in the removal of this compound.
Furthermore, in many cases, it requires considerable infrastructure, such as mixing systems, cemented tanks, and filtration stages, making these solutions larger than other systems that can be installed to treat this type of contaminant.
In addition, it can be more complex to operate and is therefore not ideal for small plants.
Adsorption using ferric hydroxide
| Pros | Cons |
| ✅ High selectivity for arsenic | ❌ Lifespan depends on water quality (ionic competition) |
| ✅ Simple operation (fixed bed) | ❌ Requires periodic media replacement |
| ✅ Low maintenance | |
| ✅ Widely implemented technology | |
| ✅ Easy solid waste management |
The use of ferric hydroxide adsorption for arsenic removal is an optimal, sustainable process.
These materials are highly selective for arsenic; in fact, this principle is similar to that used in flocculation removal processes, where the goal is to form iron hydroxide to facilitate arsenic capture.
Its operation is relatively simple, as the material is placed in a low-maintenance, fixed bed. Only periodic backwashing is required to control pressure drop.
Furthermore, its implementation is straightforward, as it can be easily integrated into existing treatment systems without requiring major infrastructure modifications.
Another advantage is the management of solid waste once the arsenic has been retained. Only the spent adsorbent material needs to be disposed of, instead of managing large volumes of sludge containing particles or other compounds, as is often the case in flocculation processes.
Its only disadvantages are the dependence on the quality of the feed water and the need to periodically replace the adsorbent medium.
Other adsorbents (TiO2, La, Zr, etc.)
| Pros | Cons |
| ✅ High laboratory testing capacity (some materials) | ❌ Limited practical experience |
| ❌ Laboratory results are not always replicable | |
| ❌ Variable and sometimes high costs | |
| ❌ Potential risk of metal leaching | |
| ❌ Periodic medium replacement |
They exhibit high performance in laboratory tests; however, practical experience is still limited.
Therefore, laboratory results are not always replicable under real-world conditions.
In some cases, these materials can be very expensive, or, for the required quantities, delivery or manufacturing times can be relatively long, making them impractical on an industrial scale.
Furthermore, there may be risks of releasing other metals, and since they are adsorbent media, they require periodic replacement.
GEH: Arsenic Removal Simply and Efficiently
GEH is a high-performance adsorbent medium made from pure synthetic ferric hydroxide.
It is presented as a dry, granular material with high porosity and a vast internal surface area of approximately 300 m²/g, which gives it a superior loading capacity for trapping contaminants.
The mechanism of action is chemical adsorption. Contaminated water passes through a fixed bed of GEH.
Arsenic adheres to the surface of the material through the formation of internal surface complexes. In this way, our solution selectively targets harmful oxoanions without altering the natural properties of the treated water.
This technology is scalable, from small cartridges for point-of-use to large municipal plants treating millions of liters.
It has been successfully implemented under difficult conditions similar to those in Mexico, including in northern Chile (where arsenic and silicates are abundant) and in water treatment plants in India and the United Kingdom.
If you want to learn more about this filter media and how to safely remove arsenic from your plant’s water without modifying existing infrastructure, contact us for personalized advice.
Sources
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