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Graphical abstract Highlights • A cost-efficient and stable BZ for HMs removal from SW have been synthesized. • Gasification of rice husk effectively improves specific surface area and pore size. • The q m values of BZ for Cu2+ and Zn2+ are 16.39 and 12.72 mg·g−1, respectively. • NH 4 +-N over 500 mg·L−1 has significant effect on the adsorption capacity of BZ. • The BZ shows higher removal efficiency of HMs than AZ and bentonite in real SW. Abstract The preparation of bentonite–zeolite (BZ) adsorbent using bentonite, aluminate, and rice husk was conducted. The adsorption experiment was performed for the removal of Cu2+ and Zn2+ from aqueous solution in single and binary systems. Results showed that gasification of rice husk could effectively improve the specific surface area and pore volume. The optimum pH for Cu2+ and Zn2+ adsorption on BZ was pH 5.0. The pseudo-first order kinetic and Langmuir isotherm model of BZ were the optimal model for Cu2+ and Zn2+. According to Langmuir isotherm model, the maximum adsorption capacity value (q m) was 16.39 and 12.72 mg·g−1 for Cu2+ and Zn2+, respectively. The adsorption affinity order of BZ in the binary solution was Cu2+ > Zn2+. NH 4 +-N concentration over 500 mg·L−1 significantly affected the adsorption capacity of BZ (P < 0.05). The adsorption capacity of BZ for Cu2+ and Zn2+ was higher than that artificial zeolite (AZ) and bentonite in SW. [ABSTRACT FROM AUTHOR]