Table 1.

Elemental quantitative analysis

Elements	Control	Acid	Alkali
C	16.43	0.62	3.16
N	14.73	16.72	9.26
O	-	-	29.25
Na	-	-	0.65
Si	1.58	0.28	0.77
S	-	-	0.18
Cl	-	-	-
Ca	-	-	0.08
Ti	66.65	82.38	55.66
Cr	0.39	-	0.43
Fe	0.21	-	0.56