Research on Experimental and Application for the High Efficient Enrichment of the Low-grade Precious Metal Materials

On the basis of reviewing the progress in the high efficient enrichment from secondary resources of low grade precious metals at home and abroad, a process route of the high efficient enrichment precious metals from secondary resources of low-grade metals by adding iron oxide as the trapping agent, reducing agent, additive, mixing uniformly and grinding, pelletizing, reduction, grinding and separation, and selectively acid leaching iron has been put forward in this paper. The experiments of reduction, grinding and separation, and selectively acid leaching iron were carried out mainly. Under the decided experiment parameters and conditions, iron generated during the reduction can trap precious metals during reduction, high active alloy powders were obtained from the reduced products by grinding and separation, the concentration of precious metals was obtained by acid leaching high active alloy powders. The better enrichment effect was obtained by adopting the technical route of processing. Other low grade noble metal materials and enrichment ratio of precious metals from the materials to acid products was high through acid leaching. This process has the advantages of simple process, environmental-friendly, strong adaptability of raw materials, high concentration ratio, which was regarded as a kind of the general efficient enrichment technology of low grade precious metal materials.

Enrichment of microplastic pollution by micro-nanobubbles

Microplastic pollution has become a global environmental concern.It has been reported that microplastics are easily accessible to a wide range of aquatic organisms and ultimately enter the human body along the food chain.They pose a severe threat to ecosystems,organisms and even human health due to their durability and persistence.However,how to reduce microplastic pollution still remains a challenge in terms of scientific techniques and policy-making.There is currently still a lack of effective methods for microplastic recycling and removal.Luckily,a new technique,micro-nanobubbles(MNBs),may provide a possible and highly effective method to enrich microplastic pollution:their great advantages[1]include a high specific surface area,long lifetime and ability to adsorb microplastics of the same size and hydrophobicity.Then they further adsorb on larger bubbles such as microbubbles or millimeter bubbles and float to the water surface together.In this study,we present a new method using MNBs to enrich microplastic pollution with high efficiency.Two types of microplastics,millimeter-scale plastic fragments and microplastic particles,were chosen as the model microplastic pollution systems to study the enrichment efficiency of MNBs on microplastics.Results showed that MNBs can efficiently enrich these microplastics.The enrichment efficiency increases with flotation time until a maximum value is reached.It is proved that MNBs not only collect the microplastic pollution but also reduce detergent use in domestic laundry sewage.This is because detergent,as a surfactant,is easily absorbed on the surface of MNBs and can be collected together with the microplastic pollution.Our research has demonstrated that the MNB technique could be promising for use in microplastic recycling and reducing detergent pollution in daily life.

AN EFFICIENT AND TARGET-ORIENTED SAMPLE ENRICHMENT METHOD FOR PREPARATIVE SEPARATION OF MINOR ALKALOIDS BY PH-ZONE-REFINING COUNTER-CURRENT CHROMATOGRAPHY

A sample enrichment method focusing on the minor targeted components was established to help them to be successfully separated by pH-zone refining CCC.Seven minor indole alkaloids in Uncaria rhynchophylla(Miq.)Miq.ex Havil(UR)were chosen to show the advantage of this method.The sample enrichment and separation were

A highly efficient method for enriching TALEN or CRISPR/Cas9-edited mutant cells

In recent years,genome editing with site-specific nucleases,such as ZFN（zinc finger nuclease）,TALEN（transcription activatorlike effector nucleases）,and CRISPR/Cas9（the type II bacterial clustered,regularly interspaced,short palindromic repeats-associated protein 9）,has gained popularity for use in cell lines,animals,and plants（Urnov et al.,2010;Miller et al.,2011;Cong et al.