Table 2 Adsorption isotherm parameters of CV and MB dyes on ASS adsorbent (adsorbent dose of 50 mg, volume of adsorbate of 20 mL, contact time of 60 min, pH of 8, and temperature of 27 °C)

Langmuir

q_m (mg g^− 1)

K_L × 10⁻² (L mg^− 1)

R ²

Freundlich

K_F ((mg g⁻¹) (L mg^− 1)^1/n)

n

R ²

Dubinin-Raduskevich

q_DR (mg g⁻¹)

B_DR × 10⁻⁶ (mol² kJ⁻²)

R ²

Temkin

b_Te (J mol⁻¹)

K_Te (L g⁻¹)

R ²