Figure 2.

Parameter sensitivity of Henry’s constant (k _d) and diffusivity (D), and SCE optimization of parameters for diffusion coupled with triple-mode sorption model. Panel (a) Countour plot showing the sensitivity of Henry’s constant (k _d) and diffusivity (D) on the objective function at 30 °C, 50 °C, and 70 °C in Zircar RS-1200. While Henry’s constant is highly sensitive, resulting in a narrow band in blue color in y-axis, diffusivity shows almost no sensitivity at all temperatures considered here. k _d profiles shown in the inset display a minima for each temperature and illustrate the high sensitivity of the parameter. Panel (b–k): SCE optimization of parameters for diffusion coupled with triple-mode sorption model in Zircar RS-1200 at 50 °C. (b): effective diffusivity (D, cm² min⁻¹), (c): desorption rate (k_s, min⁻¹), (d): Langmuir capacity ($C_{\mathrm{H}}^{\prime }$, mg g⁻¹), (e): Langmuir affinity (b ^', mg g⁻¹), (f): pooling factor (α), (g): pooling threshold ($C_{\mathrm{H}}^0$, mg g⁻¹), (h): pooling power (n), (i): Henry’s law constant (k _d, g⁻¹ cm³), (j): reduced tortuosity (τ), and (k): objective function.