▎ 摘　　要

NOVELTY - A multifunctional water purifying sand comprises sand A, bioadhesive agent B, silver nanoparticles and bioadhesive agent C with weight ratio of 100:2-20:0-19:0-10. The sand A comprises beach sand, desert sand and/or silicon dioxide microsphere. The bioadhesive agent B comprises catechol, dopamine, resveratrol, chitosan and tannic acid. The bioadhesive agent C comprises dopamine, chitosan, and/or graphene. USE - Multifunctional water purifying sand used for treating sewage containing heavy metal ion, pesticides, bacteria and/or oil substance (all claimed). ADVANTAGE - The sand solves single function, cannot be recycle and easy secondary pollution generation problems, realizes water adsorption rate of heavy metal ion and organic pesticide to 95%, and reaches sterilizing rate to 99.9% and removing oil rate to 99.9%. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) preparation of multifunctional water purifying sand comprising adding trihydroxymethyl aminomethane in reactor, adjusting pH value using hydrochloric acid to 7.5-10, adding bioadhesive agent B, stirring at room temperature for 10-60 minutes, stirring at room temperature for 3-24 hours at speed of 400-1000 revolutions/minute (rpm), washing, and drying; and (2) application of multifunctional water purifying sand comprising adding multifunctional water purifying sand with acetic acid, sewage treating, and recycling heavy metal and water purifying sand.