选矿物料中镍铜硫及氧化镁的X-荧光快速分析方法研究

针对化学分析法分析流程长、速度慢，不利二期物料现场条件的调控，影响选矿产品质量的现状，采用了直接粉末压片法，实现了选矿物料中镍、铜、硫及氧化镁的Ｘ－荧光快速分析。

Synthesis,crystal structure and adsorption properties of a novel Fe(Ⅲ) porous coordination polymer containing 1,4-naphthalenedicarboxylate ligand

A novel porous coordination polymer,iron naphthalenedicarboxylate Fe（OH）（1,4-NDC）·2H2O is hydrothermally synthesized by the reaction of FeSO4·7H2O and 1,4-naphthalenedicarboxylic acid（1,4-H2NDC） at 150℃.The compound crystallizes in a tetragonal space group P42/nmc：a=2.1447（4） nm,c=0.68849（14） nm,V=3.1669（11） nm3,Z=8,R=0.0845,wR=0.1829.The crystal structure exhibits a three-dimensional framework which is composed of infinite chains of corner-sharing octahedral Fe（OH）2O4 with 1,4-NDC ligands forming two types of channels with square-shaped cross-sections.The large channels present a cross-section of 0.76 nm×0.76 nm,while the small channels are about 0.30 nm×0.30 nm.No structural transformation occurs after removing the guest water molecules,while a robust structure generates with permanent porosity.The adsorption measurements show that the anhydrous sample of the compound can adsorb CO2 into its pores.The adsorption isotherms for methanol,acetone,tetrahydrofuran and benzene are also measured.

Flotation separation of calcareous minerals using didodecyldimethylammonium chloride as a collector

The flotation separation of scheelite from fluorite and calcite using dodecyltrimethylammonium chloride （DTAC）, dodecyldimethylbenzylammonium chloride （DDBAC）, or didodecyldimethylammonium chloride （DDDAC） as the collector has been investigated. The results show that the selectivity of these collectors for these three calcareous minerals falls in the order： DDDAC 〉 DDBAC 〉 DTAC. A significantly different flotation response of scheelite compared to the other two calcareous minerals was observed over the pH range from 7 to 8 for DDDAC as the collector. A concentrate containing 41.40% W03 could be produced from a feed mixture containing 23.22% WO3 at the DDDAC concentration of 4.0× 10^-4 mol/L. The WO3 recovery was 92.92% under these conditions. The results of zeta potential measurements suggest that electrostatic interactions are the main forces between DDDAC and the minerals. When the concentration of DDDAC is from 2× 10^-4 to 4×10-3 mol/L large differences in adsorption density, and adsorption kinetics, of DDDAC onto scheelite, calcite, and fluorite provide desirable conditions for achieving high selectivity.

Novel Palladium （II） Selective Membrane Electrode Based on Phenyl Disulfide

PVC （a poly vinyl chloride） membrane was prepared by using phenyl disulfide as a carrier for selective determination of Pd （II） ion. The membrane can be worked well over a wide concentration range （1.0 × 106-1.0 × 10-1） M with a slope 29.53 mV/decade and a limit of detection （1.77× 10-7） M. The measured of response time was 9 s. It was found to be selective and useable within the pH range （3.0-7.0）. The lifetime of membrane sensor prepared could be used for at least 4 months. The electrode was successfully used as an indicator electrode in potentiometric titration of palladium ion with EDTA.

Effect of butanol on flotation separation of quartz from hematite with N-dodecyl ethylenediamine

In order to investigate the effect of butanol on quartz flotation when N-dodecyl ethylenediamine(ND)was used as collector, single mineral flotation and artificial mixed mineral(hematite and quartz were mixed at a mass ratio of 3:2) separation were conducted in the laboratory. Experimental results indicated that addition of butanol could improve the collecting performance of ND on quartz and enhance the floatability of quartz. Best flotation recovery of quartz was obtained when butanol was mixed with ND at a mass ratio of 1:1. Moreover, the molecular structure of alcohols had a significant effect on mineral recovery. Best separation efficiency could be obtained when tert-butanol was added as it had the largest cross-sectional area. Zeta potential measurements indicated that alcohols could strengthen electrostatic adsorption between quartz and collector. Molecular dynamic simulations revealed that co-adsorption of alcohols along with ND had taken place on the quartz surface, and ND/tert-butyl combinations were more easily absorbed on the quartz surface.

Synthesize of 2,6-Di-O-acetyl Sucrose by Regioselective Acetylation with Dibutyltin Oxide

Di-O-acetyl sucrose was regioselective synthesized by using dibutyltin oxide in about 60% yield. The structure of acetyl derivative was elucidated by 1H NMR, 13C NMR, 2D-NMR and MS spectral data.

Nitrogen-doped iron for selective catalytic reduction of nitrate to dinitrogen

Nitrate is the leading cause of eutrophication worldwide and is one of the most challenging pollutants for restoration of polluted surface waters such as lakes, rivers and reservoirs. We report herein a new architecture of iron nanoparticles for high-efficiency denitrification by selective reduction of nitrate (NO3-) to dinitrogen (N2). The iron nanoparticles are doped with nitrogen (FeN) and encapsulated within a thin layer of nitride-carbon (NC). The nanoparticles have high pyrrolic N content (17.4 at.%) and large specific surface area (2040 m2/g). Laboratory experiments demonstrated high N2selectivity (91%) and nitrate removal capacity (6004 mg N/g Fe) for treatment of nitrate-containing water. This iron-based nanomaterial overcomes shortcomings of conventional catalysts by eliminating the use of precious and toxic heavy metals (e.g., Pd, Pt, Cu, Ni) and minimizing the generation of undesirable byproducts (e.g., ammonia) from the reactions with nanoscale zero-valent iron (n ZVI). The multiple electron transfers process from NO3- to N2can be fine-tuned by adjusting the NC shell thickness. Superior electrocatalytic perfor- mance, low cost and minimal environmental impact of the iron-derived nanocatalyst offer promising prospects for water purification, waste treatment and environmental remediation.