Table 5.

FTIR characteristic bands identified.

MIX	OH stretching	OH bending	Si–O/ Al-O	Si–O/ Al–O	Si–O–Si stretching	Si–O-T	Si–O–T	O–Si–O bending
M1	3452	1655	1467	991	873	584	530	466
M3	3440	1647	1423	962	871	584	538	441
M5	3457	1642	1413	970	875	585	534	445
M7	3473	1645	1412	979	875	585	539	436
M9	3430	1650	1406	954	874	585	534	435
M11	3344	1646	1408	983	872	581	536	431