Filter Contaminant Retention – Aquaphor & Q1 Test Reports

1 · What Defines an Activated Carbon Block

Highly compressed activated carbon with an enormous internal surface area – the basis for high retention

An activated carbon block is not a container filled with carbon granules. It is a solid, highly compressed body made from the finest activated carbon powder. This construction is precisely what determines what a filter can achieve – and what it cannot.

The Internal Surface Area

Activated carbon is typically produced from coconut shell and activated with steam. This creates a network of extremely fine pores. The resulting internal surface area – calculated using the BET method – is approximately 1,300 to 1,400 square metres per gram.

Three Operating Principles

Why Proximity Is Decisive

Adsorption is based on the London dispersion force, a form of the van der Waals force acting between molecules. It behaves rather like gravity – but only across an extremely short distance. The gap between the carbon surface and the molecule to be bound must therefore be very small.

This force acts additively: it is the sum of all intermolecular attractive forces. Direct contact combined with this additive effect gives activated carbon the strongest physical adsorption forces of any known material. In principle, any compound of molecular size can be adsorbed.

Block Rather Than Loose Fill

Manufacturing Makes the Difference

In a high-quality process, the activated carbon powder is coated at individual points with a porous binder and then compressed into shape. The binder content remains below 8 per cent. Two advantages follow from this:

• The pores of the activated carbon do not become clogged – the internal surface area remains usable.
• More than 90 per cent active substance is genuinely available for filtration.

Not Only Surface Area Counts – Grain Size Matters Too

Above a grain size of more than 100 µm, satisfactory adsorption results can no longer be achieved – in swimming pool applications this would not even meet DIN 19643. Powdered activated carbon in the range of 0 to 90 µm is therefore used, the majority of it around 40 µm. This is precisely why even a 5 µm activated carbon block already exhibits very high adsorption capability.

Absolute or Nominal – An Important Distinction

When comparing filter products, check whether a pore size is stated as “absolute” or as “nominal”. The number alone says little – two filters with identical ratings can perform entirely differently.

2 · The Design of the K7B / Aquadea-Q1 Cartridge

Two filter stages in one housing – adsorption and germ barrier

The K7B / Aquadea-Q1 cartridge operates in two stages. One half of the housing is occupied by the activated carbon block with AQUALEN® technology, the other half by a hollow fibre membrane. Each stage performs a different task – only together do they produce the overall result.

Stage 1Activated Carbon Block with AQUALEN®	Stage 2Hollow Fibre Membrane Germ Barrier
0.8 µmabsolute, uniform throughout	0.1 µmbacterial retention Log 6

Schematic design of the K7B / Aquadea-Q1 cartridge – flow direction from left to right

Stage 1 · Activated Carbon Block with AQUALEN®

Highly compressed activated carbon combined with AQUALEN® fibres. This stage performs the adsorption: organic substances, chlorine, pesticides, heavy metals. The filter rating is 0.8 µm absolute – and uniform throughout the entire block, not graded from the outside inwards. What “absolute” means, and why it matters, is explained in Section 1.

The patented AQUALEN® process creates additional synergy effects. The most important concerns heavy metal ions: desorption is fundamentally prevented. Desorption describes the process by which atoms or molecules leave the surface of a solid again. In practice this means that heavy metals, once bound, are held and are not washed back into the water flowing through.

Stage 2 · Hollow Fibre Membrane as a Germ Barrier

The second half of the cartridge consists of a hollow fibre membrane from a Japanese manufacturer with a pore size of 0.1 µm. It works purely mechanically: whatever is larger than the pore does not pass through.

Bacterial retention is rated at Log 6. This means a reduction by six orders of magnitude – out of one million germs in the inflow, statistically one passes the membrane. That corresponds to a retention rate of 99.9999 per cent.

How to Read the Measurements That Follow

3 · Test Bases and Standards

NSF/ANSI Standard 42 Aesthetic effects	Point-of-use (POU) and point-of-entry (POE) systems for reducing aesthetic or non-health-related contaminants: chlorine, taste, odour and particles.
NSF/ANSI Standard 53 Health effects	POU and POE systems for reducing health-related contaminants such as Cryptosporidium, Giardia, lead, volatile organic chemicals (VOC) and methyl tert-butyl ether (MTBE).
LGA	In selected products, the AQUALEN® activated carbon blocks are LGA certified.
DIN 38404-10	Calculation of the calcite dissolution capacity (Section 11).
EN ISO 11369 F12	Test method for the pesticide values of the K7B / Aquadea-Q1 cartridge (Section 5).
EN ISO 11885 E22	Test method for the heavy metal ion values of the K7B / Aquadea-Q1 cartridge (Section 5).

Test object: Aquaphor activated carbon blocks with AQUALEN® technology.

4 · Metals and Heavy Metals

Test standard analogous to NSF/ANSI Standard 53 · In-house testing, AQUAPHOR Corp. laboratory, St. Petersburg · Flow rate 2 l/min with a single cartridge

Parameter	Reduction	Note
Lead	up to 99%	NSF/ANSI Standard 53
Copper	up to 99%
Uranium	over 97%
Aluminium	over 95%
Nickel	up to 95%
Zinc	up to 95%
Iron	50 – 95%	depending on pH value
Manganese	50 – 95%	depending on pH value

5 · Extended Laboratory Data – K7B / Aquadea-Q1 Cartridge

Further contaminants · Reference values¹ · Examples of reduction

Organic Substances

Parameter	Reduction
Phenol	up to 99.5%
Chloroform	up to 99.5%
Benzene	up to 99%

Pesticides²

Parameter	Reduction
Terbuthylazine	89.3%
Isoproturon	89.1%
Sebuthylazine	88.3%
Atrazine	84.5%

Heavy Metal Ions³

Parameter	Reduction
Cadmium	99.7%
Copper	99.2%
Nickel	99.1%
Lead	98.4%

Hormones⁴

Parameter	Reduction
17-α-Ethinylestradiol	99%

6 · Retention Over the Course of the Filtrate Volume

Retention rates as a function of the water volume already filtered · Flow rate 1.5 l/min

7 · Substances Significantly Reduced

Results from Aquaphor Corp., St. Petersburg, in accordance with the Aquaphor Corp. NSF protocol

Why These Particular Substances Were Selected

• Chlorine represents water disinfection.
• Benzene represents the hydrocarbon group.
• Phenol represents organic substances. At a higher level these are grouped as TOC (total organic carbon) and VOC (volatile organic compounds), summary parameters that reflect the load carried by the water.
• Lead serves as an example of heavy metals.
• Lindane represents pesticides, fungicides and herbicides.
• Iron – iron retention at the levels stated can be regarded as a particular mark of quality.

8 · PFOA and PFOS

According to the available tests, perfluorooctanoic acid (PFOA) is retained at approximately 87 to 99%.

Measurements on the purification performance of activated carbon blocks against PFOA and PFOS in private drinking water have been published by the Hessian State Agency for Nature Conservation, Environment and Geology (HLNUG), among others.

9 · Polycyclic Aromatic Hydrocarbons (PAH)

PAHs are considered harmful to health and are classified as potential carcinogens. These molecular compounds of carbon and hydrogen atoms arise, for example, in house fires when mattresses, curtains, wooden beams, plastics or other objects made of organic materials burn. They also enter water through leaking vehicle fluids.

Activated carbon blocks are frequently used to remove PAHs from water. At an appropriate flow rate, a safe and efficient reduction can be achieved.

Applications for Activated Carbon Blocks in Water Treatment Systems

• Benzene, toluene, xylene (BTEX)
• Chlorinated hydrocarbons (CHC)
• Fluorinated hydrocarbons (CFC)
• Polycyclic aromatic hydrocarbons (PAH)
• Phenols
• Pesticides

10 · Where the Contamination Comes From

According to current knowledge and technology, traffic surfaces are to be regarded as a significant source of water pollution from stormwater discharges. Run-off from traffic surfaces is contaminated with organic pollutants from vehicle emissions, atmospheric impurities and other sources – PAHs, mineral oil hydrocarbons (MOH), methyl tert-butyl ether (MTBE) as well as plant protection and pest control products. Heavy contamination with heavy metals is added to this. The pollutants are present partly in dissolved form and partly bound to particles.

Typical Contaminants in Run-off From Paved Traffic Surfaces

Substance	Sources
Inorganic pollutants
Zinc (Zn)	Tyre wear, brake pad wear, exhaust gases, corrosion of vehicles, road signs and crash barriers
Copper (Cu)	Tyre wear, brake pad wear, exhaust gases, corrosion of vehicles
Lead (Pb)	Fuel drip losses, exhaust gases, road surface wear
Nickel (Ni)	Brake pad wear, road surface wear, catalytic converters, corrosion of vehicles
Chromium (Cr)	Tyre wear, brake pad wear
Cadmium (Cd)	Tyre wear, corrosion of vehicles
Platinum (Pt)	Catalytic converters
Organic pollutants
Mineral oil hydrocarbons (MOH)	Drip losses of engine oils, fuels and antifreeze, exhaust gases, evaporation losses
Polycyclic aromatic hydrocarbons (PAH)	Tyre wear, exhaust gases as residues of incomplete combustion, road surface wear
MTBE / ETBE	Fuel drip losses, exhaust gases as residues of incomplete combustion
Plant protection and pest control products	Drift from agriculture

11 · Calcite Dissolution Capacity

Calcite is a crystal modification – one form – of calcium carbonate (CaCO₃). The calcite dissolution capacity is the mass of calcite that one litre of water can dissolve. It is then invisibly dissolved as a salt. It is determined by calculation in accordance with DIN 38404-10 and indicates the corrosion-chemical behaviour of a water.

For calcite-depositing waters – that is, waters containing too much lime and precipitating it – the calcite dissolution capacity becomes negative.

Calcite Saturation

The state of water in which, in contact with calcite, neither dissolution nor deposition of calcite occurs: Dc = 0. Calcite saturation is also referred to as the lime–carbonic acid equilibrium.

Saturation pH Value

Also known as the pH value of calcium carbonate saturation or of calcite saturation:

CaCO₃ + H⁺  ⇄  Ca²⁺ + HCO₃⁻

In galvanised steel pipes and in copper pipes there is a clear relationship between the pH value of the water and the zinc or copper concentrations occurring in drinking water after stagnation: the lower the pH value, the higher the levels of these heavy metals in standing water. In softer waters, the same tendency applies to the solubility of lead.

To protect the consumer from excessive heavy metal concentrations in drinking water, it therefore makes sense to raise the pH value as far as possible. Raising it above 7.8 is not necessary, however. The technical limit is the pH value at which a water enters the range of calcite deposition.

12 · Your Benefits

• No turbidity – drinking water with the best taste and odour
• Two filter stages in one cartridge – adsorption and germ barrier
• Hollow fibre membrane with 0.1 µm pore size: bacterial retention Log 6 (99.9999%)
• Activated carbon block with a 0.8 µm absolute filter rating, uniform throughout – tested to NSF Standard 42
• Protection of appliances – fewer failures thanks to prevented particle ingress
• Effortless handling thanks to the quick-change system
• Innovative locking handle with secure retention

To the Aquadea activated carbon block filters

13 · Important Notes

1. The substances listed may, but need not, be present in the water.
2. Reduction results may differ in practice – both higher and lower reductions are possible. The composition of the water, the total filtrate volume, the concentration of the substance measured, the flow rate and the temperature may all deviate from laboratory conditions. The results listed are therefore to be understood as reference values. No two waters are alike.
3. The results relate exclusively to the test object named and to the test conditions described. Partial publication or reproduction of this report is permitted only with written approval.
4. It should generally be noted that every activated carbon block has a limited adsorption capacity. Tap water supplied in accordance with the Drinking Water Ordinance may contain traces of these contaminants; the capacity of the activated carbon block is sufficient to remove them within the stated filter change intervals and volumes.