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3.1.2 Chemical Properties 
From Table 1, the sum of SiO
2
+ Al
2
O
3
+Fe
2
O
3
(SAF) exceeds 70 % and thus met provisions for 
pozzolanic materials [33, 34]. Amount of SiO
2
and Al
2
O
3
in RHA and MK depicts their reactive 
capability with the primary hydrate of cement. It is interesting to note that CCW with less SiO
2
and Al
2
O
3
has the highest CaO content of 95.69 % ensuring that the Ca/Si ratio is maintained 
(kept at not less than pH 12) for reaction to continue.
3.2 Standard consistency and setting times 
3.2.1 Standard Consistency of PC-CCW-RHA-MK 
The result of standard consistency tests for the quaternary binder, PC-CCW-RHA-MK at 
different percentage replacement levels is shown in Figure 1. In a study on ternary binder with 
OPC-FA-SF at 20FA 10SF and 30FA 10 SF as replacement of OPC, it was shown that 
requirement of water increased with increase in percentage replacement level due to its fineness 
[35]. From this study, it was found that as CCW, RHA and MK replaced PC to make quaternary 
binder; the normal consistency became higher as replacement level increased. This can be 
attributed to the high fineness of RHA and MK compared with PC value. Their specific surface 
value is much higher compared with PC value (Table1). At 5 % replacement level of PC with 
CCW-RHA-MK binder, its water demand increased by 9 %, and 21 %, 39 % at 10 % and 20 % 
replacement levels, when compared to PC value (Figure 1). For the binary binders (PC-CCW, 

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Nanotechnology Applications in Africa: Opportunities and Constraints
IOP Conf. Series: Materials Science and Engineering 805 (2020) 012031
IOP Publishing
doi:10.1088/1757-899X/805/1/012031
8
PC-RHA, PC-MK), consistency is same with that of PC (control) value (Table 3) at 5 % and 10 
% replacement levels but increased by about 5 % at 20 % replacement level except for PC-CCW 
binder whose consistency is same with that of PC at all replacement levels. This showed that 
CCW does not demand much water due to its low pozzolanicity compared with RHA and MK 
values. The increase in consistency for the quaternary binder is fruitful as it facilitates more 
reactions between constituents and the primary hydrate of PC.