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Calcium-containing biochar （ES-BC） was prepared by pyrolyzing eggshell and kitchen wastes， and the ES-BC composite was used to remove phosphate （marked as ES-BC/P）. Based on the high affinity of phosphate and carbonate to lead， the ES-BC/P was then used to remove lead from the water. The results showed that， in the appropriate dosage， ES-BC/P could remove lead efficiently at different initial concentrations （1-100 mg·L -1 ）， and the removal efficiency could reach to 99%. Meanwhile， the release of phosphorus could be ignored after the reaction. As ES-BC/P was alkaline， and the lead-containing solution was weakly acidic， the addition of ES-BC/P could adjust the pH of the system automatically. The reaction kinetics and isotherm experiments showed that the lead removal by ES-BC/P was mainly monolayer chemisorption with a maximum adsorption capacity of 493.12 mg·g -1 （318 K）. The characterization results showed that lead was mainly removed through the ion exchanges of Pb 2+ in the solution with Ca 2+ in ES-BC/P. Then， the Pb 2+ combined with CO 3 2- and PO 4 2- to form many precipitates， including Pb 5 （PO 4 ） 3 OH， Pb 10 （PO 4 ） 6 （OH） 2 ， PbCO 3 ， and Pb 3 （CO 3 ） 2 （OH） 2 . In summary， the ES-BC/P material could achieve the efficient removal of lead from the water， thereby realizing the resource utilization of the wastes.

In order to solve the problem of lead removal from crude antimony in the traditional antimony refining process,NaPO3 was introduced as a lead elimination reagent to generate phosphate slag and the slag was removed by floating on the surface of liquid antimony. The reaction mechanisms were clarified by thermogravimetric-differential thermal analysis and X-ray diffraction analysis and removal of Pb from crude Sb was investigated by condition experiment. It is found that PbO and NaPO3 begin an endothermic reaction at 590℃ and mainly form NaPb4(PO4)3 and NaPbPO4 below 850℃ and above 850℃,respectively. The reaction products of the mixture of PbO,Sb2O3 and NaPO3 show that NaPO3 preferentially reacts with PbO when NaPO3 is insufficient,and amorphous antimony glass will generate only with enough NaPO3. Single-factor experiments were taken with NaNO3 as an oxidizing agent under nitrogen.Reaction time,temperature,NaPO3 and NaNO3 amounts were considered for smelting results. Under the optimal condition,the content of lead in refined antimony is 0. 047% and 98. 90% of lead is removed.