I In order to develop the design of the experiments, we first developed a fishbone diagram and based on this we developed a matrix of possible experiments using the Taguchi design explained elsewhere [11]. The analysis of fish bones was found to be as follows: - The following aspects have already been addressed in research works carried out by previous scientists: - The activity has already been studied according to order; Co2(CO)8 > Co(NO3)2> Co(CH3COO)2 while the chain growth probability followed the sequence Co(NO3)2 > Co2( CO)8 > Co(CH3COO)2 [6]. Based on these findings, Co(NO3)2 was a preferred precursor salt. Salt concentration was based on solubility in water (134 g/100 mL) and ethanol (9 g/100 mL). Usually a base is used as a precipitating agent (adjusting the pH of the system). Urea was used earlier in different experiments because its hydrolysis is slow but precipitates quickly [12]. Previous work has identified that the surface properties of the silica support, its interaction with the precursor solvent, and the pH of the system have a strong influence on catalyst dispersion. Ho et al [13] observed that when ethanol is used as the solvent instead of water for cobalt nitrate, the dispersion increases while maintaining a high degree of reduction. They proposed that the ethoxy group (-OCH2CH3) on silica gel during impregnation could hinder the aggregation of CO3O4 through physical interference during thermal decomposition of cobalt nitrate and would also affect the sintering process during reduction . It was also reported that water as a solvent formed an immobilized glassy layer following hydrogen bonding with silanol groups on the silica surface [14]. The drying speed was adjusted to ensure stability...... middle of paper......wasn't even added).Experiment PrSl PrEv DrRt CalEv RdRt1 -1 -1 -1 - 1 -12 -1 -1 +1 -1 -13 -1 -1 -1 +1 -14 - 1 -1 +1 -1 +15 -1 -1 +1 +1 -16 -1 +1 -1 - 1 -17 -1 +1 -1 +1 -18 -1 +1 +1 -1 +19 - 1 +1 +1 +1 +110 +1 +1 +1 -1 -111 +1 -1 -1 - 1 +112 +1 -1 -1 +1 +113 +1 -1 +1 -1 -114 + 1 -1 +1 +1 -115 +1 +1 -1 -1 +116 +1 +1 -1 + 1 +117 +1 +1 +1 +1 -1When selecting the final set of experiments, we limited the scope of working under the effect of solvent change and precipitation/calcination environment change (samples 2, 5, 10, 17). Our set of experiments is reduced to four, as shown in Table 3. Such an arrangement will allow stepwise identification of the impact of these factors on the final metal distribution..