Application of eco-friendly method for nano-minerals preparation and ground water treatment

This work aims at preparing different nano-minerals using bio-precipitation method (BPM). Nano-calcite (NC), nano-giorgiosite (NG), nano-witherite (NW) have been prepared by the addition of plant-derived urease enzyme (PDUE) to urea/CaCl2, urea/Ca(CH3COO)(2), urea/MgCl2 and urea/BaCl2 solutions, respectively. Nano-Mg-calcite (NMC) was precipitated by dissolving PDUE and urea in ground water (GW). Salt type plays an important role in the morphology, crystallinity, and particle size of nano-minerals. PDUE has higher effectiveness on Ca2+ removal from GW; meanwhile, it has a lower impact on Mg2+ removal. Where, the Ca-hardness varied from 1460 to 20 mg/l after the treatment of GW with PDUE. At the same pH, the Mg-hardness (1833 mg/l) slightly reduced to be 1210 mg/l. By raising pH, using one-molar sodium hydroxide solution, the removal of Mg2+ enhances. The BPM not only used to prepare innovative NMC-mineral from GW, but also applied to reduce GW-hardness.