USA Patent 005447653, EPC Patent 0612692, Japan Patent 3103475/3113183

Createrra Inc. 6-39-18, matsubara, Setagaya-ku, Tokyo 156-0043,Japan
Tel:03-5300-2501, Fax:03-5300-8287,


P-catch is a phosphorus adsorption filtration material for water purification, developed by joint research of Createrra INC, Tokyo University Department of agricultural chemistry, and Tokyo Metropolitan agricultural experiment station with Certification as Industry-academia joint research project in the fiscal year of 1991, 1992 by Tokyo Metropolis.

For its achievements P-catch won the award of excellence-new products and new technology from small business in the fiscal year of 1994.

In the same fiscal year Createrra INC. certified and Equipped funds for technical improvement to launch commercial production by Japanese Ministry of International Trade and Industry.

With those researches, mass-production system has built and succeeds to the current system.

Characteristics of P-catch
P-catch adsorbs and removes Phosphorus which is restriction factor of phytoplankton breeding when the water just pass through the filtration tank filled with P-catch.
P-catch efficiently works with the water from the low concentration (0.2 ppm) to high concentration of phosphorus.
P-catch grain has its permeability coefficient from 1 x 10-1cm/sec to 1×102cm/sec. Its high permeability allows us to use P-catch with faster water speed.
1Cubic meter of P-catch efficiently absorb phosphorus from 120Cubic meter/day of water (SV = 5).
P-catch is a Porous media which has huge amount of small pores on its surface and inside. The chemical compounds of phosphorus adsorbed from water and irons provided from P-catch are trapped in the small pores of P-catch and will not to spill. For this reason P-catch systems do not require huge sedimentation tanks for clotting method. Also expense for excess sludge disposal is not required.
P-catch can make facilities smaller, can reduce maintenance and sludge treatment cost.
After Used up, P-catch can be recycled as gardening-soil and soil improvement materials.
Since P-catch is a filtration material, pretreatment of the water to reduce suspended solids are required to prevent clogging.
Fluorine and heavy metal elements such as arsenic, selenium, zinc, lead, copper could be removed by P-catch In addition to the Phosphorus adsorption removal.
 P-catch contains SiO2, Al2O3 and Fe2O3 as the main ingredients and dose not contains Hazardous
 ingredients.(Percentage shown in dry base.)
SiO2 Al2O3 Fe2O3 TiO2 MnO CaO MgO K2O Na2O P2O5 SO3 Ignition loss
28.16 23.69 20.44 1.17 0.20 1.50 2.27 0.53 0.49 0.25 4.21 17.53

 2.Grain size

No.1 No.2 No.3
0.5~1.0mm 1.0~1.8mm 1.8~20.0mm

 3.Physical quality
 Porous media, huge surface area, ideal for a filter tank with reverse-washing systems with its High durability.

True specific gravity
Volume weight
Particle porosity
Total porosity
Coefficient of permeability
Disintegration of the back washing
Specific surface area
2.65 0.75 40.8 71.7 4.1×10-3 7.9 107


 After pounded 15times by 2.5kg metal hummer dropped from 10cm above, more than 90% of P-catch Grain retains its size of 2.0mm or greater.
Significant change of volume is not observed, after 2month use of p-catch.
After 1 year use of p-catch with reverse-washing-bubbling 10 minutes /day, 90% of P-catch Grain retains its size and shape.

 5.Chemical quality
 P-catch has adsorption capacity for both cation and anion at the same time, and has extraordinary high capacity for Phosphorus adsorption.

Phosphate absorption coefficient
(g P2O5・kg-1)
Cation exchange capacity
Anion exchange capacity
5.6 82.0 128 29

 6.Fine structure  7.Adsorption capacity

Surface is rough; 1~5 μm Fine particles are
High adsorption capacities for various concentrations of Phosphorus are shown. The measured Adsorption amounts
are 8.1~22.3g P・kg-1.

 8.Adsorption for various forms of phosphorus.  9.Effect of water speed for adsorption rate.

Phosphate, phosphtite and Tripolyphosphate removed
almost 100% after 24 hours.

When the Space flow speed decreased, phosphorus
adsorption increases.

 10.Effects of water pH for adsorption rate.  11.Effects of Coexisting ions for adsorption rate.


From pH5 to 9, adsorption of phosphate, phosphtite
and Tripolyphosphate doesn't affected.
Ion concentration
Phosphorus concentration
5.0mg・L-1 10.0mg・L-1
  0.0 100.0 100.0
AsO43- 5.0 99.6 98.8
10.0 95.0 97.0
SiO42- 50.0 96.3 96.7
100.0 91.1 88.9
F- 10.0 99.7 99.9
20.0 99.2 100.0
Cl- 100.0 99.7 99.9
200.0 99.7 100.0
SO42- 100.0 99.0 99.5
200.0 99.5 99.5
Tested with pond waters, Coexisting ions have almost
no effects on phosphorus adsorption of P-catch.


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