Beryllium adsorption from beryllium mining wastewater with novel porous lotus leaf biochar modified with PO43−/NH4+ multifunctional groups (MLLB)

Abstract Wastewater produced in beryllium mining seriously affects ecological balance and causes great environmental pressure. We designed a novel porous lotus leaf biochar modified with PO 4 3− /NH 4 + multifunctional groups (MLLB) and used it for beryllium(Be) removal from beryllium mining wastewater. Kinetic and thermodynamic experiments showed that the adsorption capacity (Q e ) of Be with MLLB from the simulated beryllium mining wastewater could reach 40.38 g kg −1 (35 °C, pH = 5.5), and the adsorption process was spontaneous and endothermic. The dispersion coefficient K d of Be with MLLB was 2.6 × 10 4 mL g −1 , which proved that MLLB had strong selective adsorption capacity for Be. Phosphoric acid, ammonia, and hydroxyl groups on the MLLB surface would complex with Be to form Be(OH) 2 and Be(NH 4 )PO 4 complexation products, which implied that surface complexation and precipitation reactions might co-existed in the adsorption process. The above results showed that MLLB could effectively adsorb Be and prevent beryllium exposure in a beryllium mining process. Graphical Abstract