Perlite

PerlitePerlite in the natural state is a dense, glassy rock formed by volcanic action. When crushed and treated under proper conditions, it pops like popcorn, expanding to 20 or more times its original volume. A special milling and classification process gives Dicalite perlite filter aids the structure and correct particle size range distribution needed for optimum performance.

Perlite is an amorphous mineral consisting of fused sodium potassium aluminium silicate. Dicalite perlite filter aids are processed at temperatures exceeding 800 C (1500 F) which eliminates organic matter. They have extremely low solubility’s in mineral and organic acids at both low and high temperatures.

Solubility’s in strong alkalis will vary according to temperature and time of contact. Dicalite perlite filter aids do not impart taste or odour to liquids being filtered.

A major advantage of Dicalite perlite filter aids is that most weigh less per unit volume than standard diatomite filter aids. Pound for pound, this gives up to 20% greater filtering capacity resulting in comparable savings in filter aid usage, especially on rotary vacuum pre-coat filters.

 

Typical Chemical Composition Perlite

Major Elements

Typical Range in %

SiO2

72

Al2O2

14

Fe2O3

0.7

Na2O

4

K2O

8.8

CaO

0.3

MgO

0.1

TiO

0.1

 

Typical Properties Dicalite Perlite Filter Aids

Product

PFRv

PCD

Float

Packaging

Data

 

min.

max.

min.

max.

max.

net kg

Sheet nr.

408

 

20

21.1

 

tr.

20 / 25

0

418

20

45

 

26

2

20 / 25

1

428

30

55

 

18.1

4

20 / 25

2

438

50

70

11.5

15.6

6

20 / 25

3

448

65

110

 

15.2

8

16 / 18 / 22

4

478

60

110

12.5

15.2

10

20 / 25

5

4108

70

120

12.5

15.2

12

20 / 25

6

4128

75

150

 

12.7

25

16 / 20 / 22

7

4158

90

165

11.0

13.6

30

16 / 20 / 25

8

4208

125

180

 

11.3

45

16 / 20

9

4258

140

210

 

10.4

70

14 / 18

10

4258-S2

150

220

 

10.2

75

14 / 18

11

4308

175

235

 

10.0

75

14 / 18

12

4358

200

260

 

10.0

80

14 / 18

13

4408

220

300

 

10.0

80

14 / 18

14

 

Notes

Permeability Flowrate (PFRv)

The constant volume filtration flowrate is measured by the permeability method (S.T.M. Nr. I-9).
This relative value gives an idea of the filtration speed.
It is the fundamental characteristic which differentiates one filteraid grade from another when the particles are formed into a filter bed or cake. Permeability is related to particle size distribution.

Permeability Cake Density (PCD)

The wet cake density is also measured by the permeability method (S.T.M. Nr. I-9).
This value gives the wet cake density in lbs/ft (x16 kg/m).
Perlite filteraids form lower density cakes than diatomite filteraids of comparable permeabilities. Densities of Dicalite perlite filteraids are controlled at a level found to be optimum for most effective performance.

Float

The float is measured by S.T.M. Nr. O-4.
This value gives the amount of floating particles in ml/20g.

 

Perlite Functional Fillers

Dicalite perlite functional fillers are a versatile family of mineral-based silicate products available throughout the world. A specialised Dicalite process incorporating expansion, selective milling, and sizing determines the particle shape of each filler product. A variety of flake or di-, tri-, and tetrahedral particle shapes are obtained by this exclusive process. These unique shapes provide numerous functions including high surface area, permeability and reinforcement and have densities among the lowest of any of the mineral fillers. In addition to superior spatial loading, this property affords customers the added bonus of density control in their finished products. Dicalite perlite fillers are off-white and do not interfere with the colouring of the products into which they are formulated.

Dicalite perlite fillers are inert to all but strong acids or alkalis and have no residual surface reactivity. After processing they are free of any organic contamination.

Dicalite offers several grades of perlite functional fillers, the most popular of which are described in the table below.

Typical Properties Dicalite Perlite Functional Fillers

 

Screen An.*

PCD

Float

Packaging

Data

Product

325

(%)

140

(%)

min.

max.

max.

net. kg

length

(cm)

colour

Sheet

Nr.

GPE-08

2-5

0-1

21.1

 

trace

20 / 25

100/110

red

0G

GPE-18

2-5

0-1

 

26

2

20 / 25

100/110

red

1G

GPE-28

2-12

0-1

 

18.1

4

20 / 25

100/110

red

2G

GPE-38

2-15

0-3

11.5

15.6

6

20 / 25

100/110

red

3G

GPE-48

5-20

0-5

 

15.2

8

16/18/22

100/110

green

4G

GPE-78

10-25

2-7

12.5

15.2

10

20 / 25

100/110

yellow

5G

GPE-108

10-35

4-8

12.5

15.2

12

20 / 25

100/110

yellow

6G

GPE-128

15-40

7-31

 

12.7

25

16/20/22

100/110

yellow

7G

GPE-158

15-45

7-31

11.0

13.6

30

16/20/25

100/110

yellow

8G

GPE-208

20-50

13-25

 

11.3

45

16 / 20

100/110

yellow

9G

GPE-258

30-55

18-25

 

10.4

70

14 / 18

100/110

yellow

10G

GPE-258 S2

35-60

18-30

 

10.2

75

14 / 18

100/110

yellow

11G

GPE-308

40-70

20-35

 

10.0

75

14 / 18

100/110

yellow

12G

GPE-358

60-75

30-45

 

10.0

80

14 / 18

100/110

yellow

13G

GPE-408

60-80

30-50

 

10.0

80

14 / 18

100/110

yellow

14G

   * Retained on U.S. Std. Sieve 325 Mesh = 0.044 mm, 140 Mesh = 0.105 mm (wet screening).