For over fifty years, Multipure has stood at the forefront of point-of-use drinking water treatment and water filtration technology. At the heart of our industry-leading water filter technology is the development, refinement, and usage of our proprietary solid carbon block filters. But what makes a Multipure carbon block the best choice for water filters?

The short answer: Multipure carbon block filters offer the best water filtration performance due to a combination of effectiveness, efficiency, and convenience.

Carbon Block Filters

The key to the performance of our solid carbon block filters is in the design; not all carbon blocks are the same, and Multipure uses a proprietary blend of carbon and other filtration media that has been developed and refined for over 50 years. The result is a high-capacity filter that treats a broad range of contaminants while maintaining a high flow rate. And, unlike granular activated carbon (GAC) –a loose collection of carbon particles – our carbon blocks are formed from a densely compressed formulation of materials.

Why is compression important?

Compression is an important element of a good carbon block filter. A properly formed carbon block ensures that the carbon and other filtration media are compressed evenly. This ensures that the filtration action is the same throughout the block, enhancing the kinetics of the filter by creating a large and consistent surface area for water contact, therefore facilitating better contaminant adsorption. Because water spends a longer time in contact with the carbon as it passes through the densely packed media, it allows for greater opportunities to trap or adsorb a wide variety of waterborne contaminants including pesticides, herbicides, and heavy metals.

Multipure expands on this with an additional pre-filter wrapped around the carbon block, enabling the filter cartridge to treat larger particles in the water before the water enters the carbon block, enhancing the filtration performance and preventing premature clogging.

Why is carbon important?

Carbon has long been a material of choice when it comes to water filtration due to its inherent qualities. Contaminants are naturally drawn to activated carbon, adhering to the surface of the carbon in a process known as physical adsorption, and therefore acting as one method of contaminant treatment in the water. In addition, carbon is a highly porous material, which enables the carbon to physically trap contaminant particles within the pores, removing contaminants in a method known as mechanical filtration. Furthermore, Multipure’s carbon block filters feature an outer filter wrap that not only mechanically filters out large particles from the water, but also adds a third water treatment method: the filter wrap’s positive ionic charge attracts negatively-charged contaminant particles to adhere to its surface, removing contaminants in a method known as electrokinetic adsorption. Even greater filtration capabilities have been added by Multipure’s carbon blocks through the addition of specialized media to the carbon formulation, enabling the filtration of substances such as arsenic-V and pharmaceuticals, enhancing the already powerful filtration qualities of the carbon itself.

While GAC offers some filtration ability due to the nature of carbon, solid carbon blocks are advantageous in that the compressed carbon provides a tremendous surface area and contact time advantage over GAC. Greater surface area, and greater contact time, means greater filtration ability. GAC typically uses gravity to pull water through the filtration media, but because GAC is a loose collection of particles, contaminated water can bypass the filter through larger gaps in the GAC – an occurrence known as “channeling,” since the water forms an unobstructed channel through the filter media to take the path of least resistance.

Why is water pressure important?

Active water pressure allows the inflow water to be forced through the densely compressed yet porous material of the carbon block, enabling filtration without sacrificing water flow. With the water pressure applied to a carbon block filter, excess raw water pressure is not lost when the filtration process takes place – as is often the case with gravity filter systems. This means that a drinking water system that uses water pressure to push water through a carbon block delivers cleaner water quickly and continuously as needed. Gravity-fed filters and reverse osmosis (RO) systems both work slowly enough that they cannot offer filtered water in real time; instead, both RO and gravity-fed filters slowly fill a reservoir with filtered water. When the reservoir is empty, it can take hours before filtered water becomes available in usable quantities.

In fact, a typical gravity flow carbon block filtration system may have a 2.5-gallon filtered water reservoir, but a flow rate of only 3.5 gallons per hour. If, for example, you needed to use 3 gallons of water at one time, perhaps for cooking and serving as drinks, once that 2.5-gallon reservoir is empty, it will take almost an hour to refill it.

On the other hand, by using the active water pressure of a sink faucet or a sink’s plumbing, a Multipure carbon block filtration system can provide up to 1 gallon per minute of filtered water – over 17 times faster than the typical gravity flow filter – all without sacrificing filtration performance! This makes it feasible to use Multipure filtered water not just for drinking, or just for cooking, but also for washing and preparing fruits, vegetables, rice, or any other foods, allowing you to prepare healthier meals in general. That is the advantage of a Multipure carbon block drinking water system.

Why is a unified filter design important?

Multiple filters does not mean a drinking water system is more powerful or more capable. But, it does mean that you need to keep track of the capacity and maintenance of more filters. It means that you have to pay for, store, and dispose of more filters. Even more importantly, the additional complexity of a multi-filter system means that the improper maintenance of just one filter can negatively impact the performance of the system as a whole.

Multipure filter cartridges

Multipure designs its systems so that all the filtration performance and capabilities are contained within one easy-to-change filter cartridge. This unified filter design means there is only one capacity rating you need to think about, since the capacity ratings applies to every type of contaminant treated by the filter cartridge. When the capacity is reached – or once a year, on average – you only need to change one filter cartridge to maintain maximum performance from your system.

Why is installation versatility important?

Multipure’s drinking water systems are designed so that all models have the ability to be used on the countertop, below the sink, or even inline with your refrigerator. By comparison, many gravity-fed systems cannot be installed below the sink, and many RO systems are too large and cumbersome to be installed on the countertop.

Why is NSF certification important?

Multipure’s drinking water systems offer performance that is independently tested and certified by NSF International. These certifications test our carbon block filters for the entire capacity of the filter under real-life usage conditions; many non-certified systems only test for a small percentage of their filters’ capacity, and even then under controlled circumstances that maximize the performance data, such as testing under lower flow rates than would be used in real life. This is a big difference between Multipure’s carbon block drinking water systems compared to other companies’ offerings. When a system is NSF certified, it means that the performance claims of that system are absolutely trustworthy, because they have been rigorously tested at all steps of production, and tested both in the laboratory and in the real world.

Why are Multipure carbon block systems important?

Multipure Solid Carbon Block

Ultimately, solid carbon blocks serve as a highly effective, efficient, and convenient solution to cleaner, healthier water. Carbon blocks refine the inherent advantages of carbon (and GAC) as a filtration medium, making it more powerful by increasing its ability to contact water and treat the contaminants that may be present, and versatile enough to add additional filtration capabilities through distinct carbon block formulations. Multipure’s carbon block filtration systems add to this advantage by using active water pressure to avoid the slow action of gravity filters and the need for filtered water reservoirs, giving you an abundance of filtered water without any wait times. With installation and usage versatility, coupled with the performance integrity that comes from independent, third-party NSF certification, Multipure and our carbon block drinking water systems demonstrate themselves to be the superior choice for your water filtration needs.