The effects of cobalt carbide ($C{o}_{2}C$) catalyst particle size and usage ratio ($H_2/CO$) on the Fischer-Tropsch selectivity, cobalt time yield and turnover frequency were investigated through statistical modeling by means of response surface methodology based on the data obtained over seven $Si{O}_2$ supported cobalt catalysts at three different usage ratio levels. The effects of predictor variables on responses are illustrated in contour and surface plots and analyzed based on both model equation and plots. C₅₊ selectivity was found to increase with increasing $C{o}_{2}C$ particle size up to the range of 9.6–11.75 nm, after which decreases slightly. Furthermore, a linear relationship was detected between CH₄ selectivity and C₅₊ selectivity for predicted data at all $H_2/CO$ ratios (0.5–2) in the $C{o}_{2}C$ particle size range of 5.3–9.4 nm. Multi-objective optimization conducted for the enhancement of C₅₊ selectivity predicted the particle size of 6.795 nm and usage ratio of 0.500 as optimum conditions.

碳化钴的作用（$C{Ø}_{2}C$）催化剂的粒径和使用率（$H_2/CØ$费-托选择性，通过基于响应面法的统计模型，基于七个以上的数据，研究了钴的时间产量和周转频率 $\mathrm{小号}\mathrm{一世}{Ø}_2$在三种不同的使用率水平下负载的钴催化剂。预测变量对响应的影响在等高线和曲面图中进行了说明，并基于模型方程式和图进行了分析。发现C _5+的选择性随着增加而增加$C{Ø}_{2}C$粒径可达9.6-11.75 nm，此后略有减小。此外，检测到CH ₄选择性和C ₅₊选择性之间的线性关系$H_2/CØ$ 比率（0.5–2）在 $C{Ø}_{2}C$粒径范围为5.3–9.4 nm。为提高C ₅₊选择性而进行的多目标优化预测最佳条件为6.795 nm的粒径和0.500的使用率。