heavy metals removal from synthetic wastewater through layered double hydroxide (ldh)(mg-al)-hydrochar

An experiment was conducted to explore the potential use of coconut shell hydrochar (cshc) using batch adsorption. cshc-ldh (mg-al) is mixed with layered double hydroxide (ldh) to remove ni (ii), cd (ii), and zn (ii) from a ternary-metal solution (with a mixing ratio of 0.5:0.3:0.2). we investigated the effects of initial concentrations, ph, adsorbent dosages, and contact time through adsorption kinetic and isotherm studies. the optimal conditions that give higher removal percentages were: ph of 6 and 4, adsorbent dose 1 and 0.7 mg, initial metals concentration 250 mg/l, and the equilibrium time of 90 min for cshc and cshc/mgal-ldh, respectively. the cshc and cshc/mgal-ldh composite revealed a strong sorption ability to cd (ii), ni (ii), and zn(ii) in aqueous solutions with the langmuir maximum adsorption capacity of 188.67, 204.08, and 222.22 mg/g and 312.5, 344.82, and 357.14 mg/g, respectively. the adsorption kinetic study revealed that the adsorption process followed second-order kinetics. the batch experiment results showed that the cshc and cshc-mg-al ldh were effective in the simultaneous removal of ni (ii), cd (ii), and zn (ii) to a significant extent. the cshc-mg-al ldh composite has demonstrated considerable promise in removing heavy metals from wastewater. it offers the benefits of easy synthesis and exceptional adsorption capability.