Ethylenediamine tetramethylenephosphonic acid as a selective collector for the improved separation of chalcopyrite against pyrite at low alkalinity

Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment and associated precious metals recovery. Therefore, in this study, the green and odourless ethylenediamine tetramethylenephosphonic acid(EDTMPA) was introduced as a novel chalcopyrite collector. Flotation results from the binary mineral mixture and real ore demonstrated that EDTMPA could realize the selective separation of chalcopyrite from pyrite relative to ethyl xanthate(EX) without any depressants within the wide p H range of 6.0–11.0, and might replace the traditional high-alkaline lime process. Electrochemical and Fourier transform infrared spectra measurements indicated that the difference in adsorption performance of EDTMPA on chalcopyrite and pyrite was larger than that of EX, suggesting a better selectivity for EDTMPA. Density functional theory calculations demonstrated that there were stronger chemical bonds between P—O groups of EDTMPA and the Fe/Cu atoms on chalcopyrite in the form of a stable six-membered ring. Crystal chemistry calculations further revealed that the activity of metal atoms of chalcopyrite was higher than that of pyrite. Therefore, these basic theoretical results and practical application provide a guidance for the industrial application of EDTMPA in chalcopyrite flotation.

α-Oxoketene Cyclic S, S-cetals Chemistry-Substitution Reaction of α,α'-Dicinnamoyl Ketene Cyclic S, S-Acetals with Ethylenediamine

α,α’-Dicinnamoyl ketene cyclic S, S-acetals 4 were reacted with ethylenediamine to afford α,α’-dicinnamoyl ketene cyclic N,N-acetals 5. This process provides a new method for thesynthesis of 5 in high yield under mild conditions.

STUDIES OF THE INITIATION MECHANISM OF VINYL POLYMERIZATION WITH THE SYSTEM PERSULFATE/N-ALKYL SUBSTITUTED ETHYLENEDIAMINE DERIVATIVES

Effects of N-alkyi substituted ethylenediamine derivatives on vinyl polymerization using persulfate as initiator were studied. The apparent kinetic equations and overall activation energies of acrylamide polymerization were determined using the above mentioned system as initiator. The promoting activities of different diamine derivatives on vinyl polymerization are in the order of tertiary diamine】secondary diamine】primary diamine. Diamines having methyl groups as the substituent on their nitrogen atom possess higher promoting activity than that of having larger alkyl groups. The initial free radicals produced through the redox reaction of persuifate and diamines were studied by spin strapping technique and ESR spectroscopy. The results obtained confirm the fact that the initial free radicals of the diamine species can initiate vinyl polymerization and become the amino end group of the resulting polymers.

Electroless copper plating process of N, N, N, N′-tetrakis (2-hydroxypropyl) ethylenediamine system with high plating rate

Electroless copper plating process of N, N, N′, N′-tetrakis (2-hydroxypropyl)ethylenediamine(THPED) chelating agent was researched comprehensively. The results indicate that plating rate decreases with the 3H2O has a bad effect on deposits quality, but 2, 2′-dipyridyl and PEG make deposits quality improve greatly. Low concentration of 2-mercaptobenzothiozole (2-MBT) increases plating rate and improves deposits quality, but decreases plating rate and worsens deposits quality when 2-MBT reaches 5 mg/L. The optimal conditions of this electroless MBT are 16.8 g/L, 16.0 mL/L, 13.3 g/L, 0.5 g/L, 5.0 mg/L and 2.0 mg/L, respectively, pH value is 12.75,bath temperature is 30 ℃. Plating rate reaches 9.54 μm/h plating for 30 min in the bath. The SEM images demonstrate that the surface of copper film is smooth and the crystal is fine.

Synthesis and Characterization of Free and Copper (II) Complex of N,N′-<i>Bis</i>(Salicylidene)Ethylenediamine for Application in Dye Sensitized Solar Cells

Dye sensitized solar cell represents a promising method for the conversion of solar energy to electric energy. In the present work free N,N'-bis(salicyli-dene)ethylenediamine and its copper (II) complex were synthesized, characterized, and investigated for use as dye sensitizers in the fabrication of dye sensitized solar cells. The dyes were characterized using UV-Vis, Steady State Florescence, and Fluorescence Lifetime, Thermogravimetric Analysis, Differential Scanning Calorimetry, and Cyclic Voltammetry. The thermogravimetric analyses of the ligand and the ligand Copper complex demonstrate the stabilizing effect of the copper ion on the ligand complex. Additionally, the copper ion is shown to stabilize the structure, as evidenced by the 150oC increase in the extrapolated onset temperature of the decomposition event. The ligand copper complex is further stabilized by the presence of the copper, which is determined by the 6.34% residue that remained at the end of the thermogravimetric analysis, compared with 0% residue when applying the same condition for the ligand without copper. The current-voltage characteristics of the cells and the electrochemical impedance were determined. The photovoltaic performance of the solar cell devices fabricated using N,N'-bis(salicylidene) ethylenediamine dye was found to be slightly better than those produced from the copper complex. The solar to electric power efficiency of the ligand-based dye sensitized solar cell was 0.14% and that of the copper complex was found to 0.12%. Although the difference in the cell efficiency is quite small, it is obvious that the insertion of Copper into the ligand did not enhance the performance of the solar cells. The photocurrent-photovoltage results are consistent with the absorption spectra that showed a more prominent band for the ligand. The free hydroxyl groups, present in the ligand but absent from the copper complex owing to their coordination with the copper metal, could be responsible for the difference in the performance of the devices. The hydroxyl groups get attached to the TiO2 and facilitate the transfer of electrons.

Cosmetic Lifting Effect of a Formula Combining Tetrahydroxypropyl Ethylenediamine, Ononis Spinosa and Glycerin as Shown by a New 2-D Imaging Method

Facial sagging is a major aging change that affects the overall shape of the face. Sagging can negatively impact self-perception and consequently quality of life. In order to fight against this aging sign, we developed a combination of three active ingredients: Tetrahydroxypropyl Ethylenediamine (THPE), Ononis Spinosa extract and Glycerin. In a clinical study, we assessed the efficacy of this association on facial sagging and wrinkles, with a special focus on immediate and lasting effects. Thirty-nine women applied the tested product daily during an eight-week treatment period. Clinical grading by experts and a new, easy to operate, 2-D imaging method were performed at different time points. The 2-D imaging method measured the upper eyelid lifting effect. The results showed an immediate and significant improvement in sagging and wrinkle parameters;these benefits were still observed seven hours after the first application. Results also showed a significant long-term improvement. The lifting effect calculated from the 2-D pictures was 1.08 mm immediately after application;the same method showed a 1.80 mm lifting effect following the eight-week treatment period. These results suggest that a skin care product combining THPE, Ononis Spinosa and Glycerin properties may be used to reduce sagging as well as wrinkles with both immediate and long term benefits.

Water-soluble pillar[4]arene[1]quinone: Synthesis, host-guest property and application in the fluorescence turn-on sensing of ethylenediamine in aqueous solution, organic solvent and air

Water-soluble pillar[5]arenes are a class of typical macrocycles and have aroused tremendous attention for its easy to modify, abundant host-guest properties and extensive applications. However, up to now, all the reported water-soluble pillar[5]arenes acted as the host molecules, whereas they failed to be postsynthetically modified, which seriously impeded the development of the pillar[5]arene-based supramolecular chemistry. In this work, a new water-soluble pillar[5]arene, pillar[4]arene[1]quinone, was designed and synthsized with eight quaternary ammonium groups as well as a quinone units. Such a new water-soluble pillar[4]arene[1]quinone was capable of forming 1:1 stable complex with sodium 1-octanesulfonate in aqueous solution. Since the 1,4-quinone unit of WP[4]Q[1] could react with ethylenediamine (EDA) to form a conjugated quinoxaline structure, so pillar[4]arene[1]quinone could apply to the facile fluorescence turn-on sensing of EDA in aqueous solution, organic solvent and air.

Application of EDTMPS as a novel calcite depressant in scheelite flotation

In this study, the innovative use of ethylenediamine tetramethylene phosphonic sodium(EDTMPS) as a calcite depressant in scheelite flotation was investigated by flotation experiments, and its selective depression mechanism was revealed by contact angle measurement, FTIR analysis, Zeta potential test and XPS analysis. The flotation experiment results showed that scheelite and calcite could be efficiently separated under the following conditions: pulp p H=9.5, Na OL concentration of 1.5×10^(-4)mol/L, EDTMPS concentration of 3.0×10^(-5)mol/L, a scheelite concentrate with WO3grade of 65.49%, recovery of 83.29%and separation efficiency of 65.29% could be obtained from the artificially mixed minerals. The analysis results of mineral surface properties demonstrated that EDTMPS was strongly adsorbed onto the calcite surface through the reaction between the phosphonate group and the calcium ions, which hindered Na OL adsorption and increased the hydrophilicity of calcite. However, EDTMPS had weak adsorption strength on the scheelite surface, which didn’t affect further adsorption of Na OL, hence, the scheelite remained hydrophobic. Consequently, the selective adsorption of EDTMPS on the two minerals’ surfaces increased a difference in wettability and thus enabling them to be separated by flotation. Finally, the mechanism model of this flotation separation process was established.

Effect of Amine Type on Lignin Modification to Evaluate Its Reactivity in Polyol Construction for Non-Isocyanate Polyurethanes(NIPU)

Polyols are groups of organic compounds which contain carbon and are randomly linked to other atoms,especially carbon-carbon and carbon-hydrogen.These compounds are mainly used as reactants to make other polymers.Among biopolymers,lignin is regarded as the base of a new polymer in polyol construction.The present study aimed to investigate the effects of amine type(diethylenetriamine and ethylenediamine)on the modification of lignin-based polyols,so as to provide an alternative to petroleum polyols and,in turn,increase functional groups and reduce their harm to humans’health and the environment.To this aim,first,lignin was extracted from raw liquor.Next,the extracted lignin was reacted with diethylenetriamine(DETA)and ethylenediamine(EDA).Finally,the Mannich method was used for the reaction between amine lignin and propylene carbonate.The results of the Fourier Transform Infrared(FTIR)spectroscopy analysis showed that modification with DETA led to more structural change in lignin and peak 1100 indicates the presence of C–O bond related to urethane bonds in modified lignin.Moreover,adding propylene carbonate to aminated lignin did not result in much change in the results of the FTIR analysis.Additionally,urethane bonds can be seen in the results of GPC at 400℃–500℃.Furthermore,a slight decrease in thermal stability was observed in lignin modified with amine and propylene carbonate,compared to the raw lignin sample.

Amine-immobilized HY zeolite for CO_(2) capture from hot flue gas

Solid amine-based adsorbents were widely studied as an alternative to liquid amine for post-combustion CO_(2)capture(PCC).However,most of the amine adsorbents suffer from low thermal stability and poor cyclic regenerability at the temperature of hot flue gases.Here we present an amine loaded proton type Y zeolite(HY)where the amines namely monoethanolamine(MEA)and ethylenediamine(ED)are chemical immobilized via ionic bond to the zeolite framework to overcome the amine degradation problem.The MEA and ED of 5%,10%and 20%(mass)concentration-immobilized zeolites were characterized by X-ray diffraction,Fourier-transform infrared spectroscopy,and N_(2)-196℃ adsorption to confirm the structure integrity,amine functionalization,and surface area,respectively.The determination of the amine loading was given by C,H,N elemental analysis showing that ED has successfully grafted almost twice as many amino groups as MEA within the same solvent concentration.CO_(2)adsorption capacity and thermal stability of these samples were measured using thermogravimetric analyser.The adsorption performance was tested at the adsorption temperature of 30,60 and 90℃,respectively using pure CO_(2)while the desorption was carried out with pure N_(2)purge at the same temperature and then followed by elevated temperature at 150℃.It was found that all the amine@HY have a substantial high selectivity of CO_(2)over N_(2).The sample 20%ED@HY has the highest CO_(2)adsorption capacity of1.76 mmol·g^(-1)at 90℃ higher than the capacity on parent Na Y zeolite(1.45 mmol·g^(-1)only).The amine@HY samples presented superior performance in cyclic thermal stability in the condition of the adsorption temperature of 90℃ and the desorption temperature of 150℃.These findings will foster the design of better adsorbents for CO_(2)capture from flue gas in post-combustion power plants.

CONDENSATION OF 1,2-DIAMINES AND CARBOXYLICACIDS UNDER MICROWAVE IRRADIATION

A facile method of preparation of benzimidazoles by microwave irradiation was described. The mixtures of o-phenylenediamine and carboxylic acids were heated by microwave irradiation, to give 2-substituted benzimidazoles with yields of 49%～93%. The reaction time was shortened to 3～6 min. However, the reaction of ethylenediamine with carboxylic acids did not give imidazoles but the N,N-diacyl ethylenediamines. The alphatic diamines lacked the activity to form imidazole ring. With adipic acid, intermolecular acylation took place to afford poly(ethylene adipamide).

Hydroxy- and Aminoethyl Imidazolines of Cottonseed Oil Fatty Acids as Additives for Diesel Fuels

In the research, aminoethyl imidazolines of cottonseed oil fatty acids with diethylenetriamine have been synthesized using the ultrasonic device creating the effect of cavitation. The yield of imidazolines was 90% - 95%. The influence of the synthesized imidazolines on lubricity quality of low sulfur diesel fuels having low lubricating quality was studied. The results showed that at concentrations 200 - 250 ppm the synthesized imidazolines can be applied as additives enhancing lubricity quality of diesel fuels.

Influence of the morphology on mechanical properties of toughened epoxies with CTBN

Presents a toughened epoxy risen based on diglycidylether of bisphenol A (DGEBA) cured with ethylene diamine (EDA) and modified with a carboxyl terminated acrylonitrile butadiene (CTBN), studies morphologies with different rubber content and analyses the influence of rubber phase morphology corresponding to different rubber contents on mechanical properties (elastic modulus, uniaxial compression yield stress, shearing strength, uneven tensile strength, critical stress intensity factor K ic  and strain energy release rate G ic ) of toughened epoxies.

Novel and Validated Spectrophotometric Matrix Matching Method for Simple and Rapid Determination of Chromium in Oily Media

N,N'-bis(4-methoxysalicylidene)ethylenediamine is proposed as analytical reagent for the direct determination of chromium in original matrix of liquid oils.The method is based on the complexation of N,N'-bis(4-methoxysalicylidene)ethylenediamine and chromium in n-hexane∶acetone(1∶4)medium and spectrophotometric determination at 355 nm against reagent blank.Complexation of MSE and chromium is completed in20 seconds at molar ratio 1∶1.The molar absorptivity and the formation constant of the complex are determined as 9 740L·mol^(-1)·cm^(-1) and 3.6(±0.1)×10~5,respectively.Beer's law is obeyed in range 0.02~1.50mg·L^(-1) chromium concentration.Limits of detection and quantification of the suggested method were7.5 and 25.11μg·kg-,respectively.The accuracy and precision of the method was checked by finding mean recovery and relative standard deviation by oil-based chromium standard analysis as 96.4%±1.4%and 1.5%,respectively.The practical applicability of elaborate method was tested using oil-based chromium standard spiked and unspiked corn,sunflower,soybean,olive and canola oils.

New Dimeric Selenidoarsenate(III):Solvothermal Synthesis and Crystal Structure of [Co(en)_3]_2As_2Se_5

A new selenidoarsenate [Co(en)3]2As2Se5 1 (en = ethylenediamine) was synthesi- zed by a reaction of AsCl3, CoCl2(6H2O and Se in en under mild solvothermal conditions, and the structure was determined by single-crystal X-ray diffraction. 1 crystallizes in the orthorhombic system, space group Pbca with a = 15.5092(12), b = 11.5756(9), c = 17.8138(14) , V = 3198.1(4) 3, Mr = 1023.12, Z = 4, Dc = 2.125 g/cm3, ( = 8.807 mm-1, F(000) = 1976, S = 1.171, the final R = 0.0591 and wR = 0.1067 for 3170 observed reflections with I > 2((I). 1 consists of isolated dimeric [As2Se5]4- anion constructed by two corner-sharing AsSe3 trigonal pyramids and transition metal [Co(en)3]2+ cations. The optical absorption property and thermal stability of 1 are reported.

Comparative Efficacy of Polyamine-Based Scavenger Resins

Polyamine-based scavenger resins containing 2, 3 and 4 nitrogen atoms have been prepared and their comparative efficacy to scavenge appropriate electrophilic chemicals (acids, acid chlorides, isocyanates and aldehydes) from solutions has been studied. As expected, the scavenging efficiency is directly proportional to the number of nucleophic nitrogens present on the resin. The results have been compared with the performance of the popular scavenger resin, namely, tris(2-aminoethyl)amine resin, to conclude that the low-cost polyamine resins now prepared can be conveniently used as effectively as the expensive commercial product.

Synthesis of Folate-Appended <i>β</i>-Cyclodextrin Using Phenanthroline as Linker for Cancer Targeting Drug Delivery

Here we have synthesized cancer targeting drug delivery system that contains β-cyclodextrin as a drug carrier and folic acid as a targeting ligand. Folic acid was selected as a cancer targeting ligand because folic acid receptors are highly expressed in a variety of tumor types. β-cyclodextrin and folic acid were connected through a linker [1,10-phenanthroline or 5-(hydroxymethyl) furfural]. β-cyclodextrin and folic acid were attached to the linker by formation of Schiffbase and ester, respectively. Our targeted synthetic products were confirmed by NMR, Mass and IR spectroscopy. We anticipate that our synthetic products can confer cancer cell-specific drug delivery as well as desired properties such as nanoparticle formation.

Syntheses of Coordination Compounds of 2-Amino-3-Methylbutanoic Acid Their Mixed Ligand Complexes and Antibacterial Activities

Coordination compounds of 2-amino-3-methylbutanoic acid were synthesized with chromium(III) and oxovanadium(IV) ions. M:L;1:2. Adducts of these complexes using 1,10-phenantroline and ethylenediamine were further synthesized, M:L, (1:2). These compounds were characterized using electronic, infra-red spectrophotometry, magnetic susceptibility measurement and percentage metal analyses. The zones of inhibition and minimum inhibitory concentrations of the compounds against eight microbes were studied. The results obtained indicated an octahedral geometry for the Cr(III) complexes, indicative of additional coordination of two water molecules. On the other hand a square pyramid geometry was obtained for the binary oxovanadium complex and its 1,10-phenantroline adduct. However, for the oxovanadium ethylenediamine adduct a distorted octahedral geometry was proposed. The result for the antibacterial studies indicated that both mixed ligand complexes of 1,10-phenantroline exhibited good antibacterial activity, and in some cases better activity than the standard, streptomycin.