Table 2 Chemical composition of Commercially Available Ceramic Water Filters (CWFs) (%)

SiO₂

45.34

55.24

3.55

47.34

44.62

Al₂O₃

10.14

8.46

1.18

20.73

7.18

Fe₂O₃

5.13

0.48

0.39

1.12

0.39

CaO

0.075

10.69

1.63

3.23

8.54

K₂O

2.57

3.28

0.82

0.46

2.64

TiO₂

0.74

n.d

n.d

1.29

n.d

MnO

0.031

0.020

0.0079

0.0085

0.015

MgO

n.d

n.d

1.82

n.d

n.d

I.L

35.55

21.62

89.67

25.62

36.41

SiO₂/Al₂O₃ molar ratio

⁓ 4

⁓ 6

⁓ 3

⁓ 2

⁓ 5