Silver nanoparticles (AgNPs) and silver/quartz nanocomposite (Ag/Q)NPs)) were synthesized by sol-gel method using table sugar as chelating agent. The synthesized nanosized materials were used for mercury ions adsorption from aqueous solutions. The materials were characterized by X-ray diffraction (XRD), Transmission Electron microscope (TEM), and surface area (BET). Adsorption of Hg2+ (10 mg/l) is strongly dependent on time, initial metal concentration, dose of adsorbent and pH value. Silver/quartz nanocomposite ((Ag/Q)NPs)) shows better efficiency than individual silver nanoparticles (AgNPs). This composite removed mercury ions from the aqueous solution with efficiency of 96% at 60 min with 0.5g adsorbent dosage at pH 6. The adsorption process explained well by the pseudo-second-order kinetic model. In conclusion silver/quartz nanocomposite (Ag/Q)NPs)) shows higher removal efficiency for mercury ions from aqueous solutions than individual silver naoparticles (AgNPs) or quartz (Q).

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In recent years mining industry has been facing several problems that influence it. The former aspect compels the mining industry to process low grade ores, fine mineral particles and flotation tailings to produce material suitable for a global market. So it has become very important to develop appropriate and environmentally friendly technologies able to replace the conventional techniques used for the mineral beneficiation. The bio-beneficiation process using microbes adapted from the surface of the rock is the method for choice to removal of undesirable gangue minerals from the desired valuable phosphate (apatite) minerals. Through this study, a concentrate with 18.5% P2O5 and 33.03 % sio2has been obtained from a binary mixture having11.65% P2O5 and sio2 40.98 %. On applying the optimum conditions on natural phosphate ore containing 21.89%, a concentrate with 27.2 % P2O5 has been obtained on using bioflotation process with Bacillus cereus bacteria.

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