scholarly journals A novel application of hematite precipitation for high effective separation of Fe from Nd-Fe-B scrap

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Xue Lin ◽  
Zhan Qu ◽  
Yu Chen ◽  
Ruinan Jin ◽  
Ting Su ◽  
...  
Keyword(s):  
Nitric Acid ◽  
Rare Earths ◽  
Precipitation Method ◽  
Rare Metals ◽  
Acid Dissolution ◽  
Sintered Magnet ◽  
Major Mechanism ◽  
Novel Approach ◽  
Hydrochloric And Sulfuric Acids ◽  
Hydrolysis Of

AbstractRare earths, e.g. neodymium (Nd), praseodymium (Pr) and dysprosium (Dy), are abundant in the rare earth sintered magnet scrap (Nd-Fe-B scrap), but their recycling is tedious and costly due to the high content of impurity Fe. Herein, a novel approach was developed to effectively recycle rare earths from the scrap via an integrated acid dissolution and hematite precipitation method. The scrap contained 63.4% Fe, 21.6% Nd, 8.1% Pr and 3.9% Dy. It was dissolved in nitric, hydrochloric and sulfuric acids, separately. Nearly all impurity Fe in the scrap was converted to Fe3+ in nitric acid but was converted to Fe2+ in hydrochloric and sulfuric acids. After hydrothermal treatment, the rare earths in the three acids were almost unchanged. From nitric acid, 77.6% of total Fe was removed, but total Fe was not from the hydrochloric and sulfuric acids. By adding glucose, the removal of total Fe was further increased to 99.7% in nitric acid, and 97% of rare earths remained. The major mechanism underlying total Fe removal in nitric acid was the hydrolysis of Fe3+ into hematite, which was promoted by the consumption of nitrate during glucose oxidation. This method effectively recycled rare metals from the waste Nd-Fe-B scrap and showed great potential for industrial application.

Acalypha Indica mediated MgO NPs: A novel approach in greener route with its antibacterial activity against pathogens

2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Kavipriya K C ◽  
Sudha A P ◽  
Sujatha K ◽  
Sowmya Lakshmi K
Keyword(s):  
Antibacterial Activity ◽  
Metal Oxides ◽  
Bacterial Species ◽  
Magnesium Nitrate ◽  
Precipitation Method ◽  
Average Crystalline Size ◽  
Face Centered Cubic ◽  
X Ray ◽  
Novel Approach ◽  
Acalypha Indica

The interest in miniaturization of particles revealed the hidden applications of metal oxides. The potential applications of the particles may vary when the size of the particle is reduced. One of the alternative routes to the conventional approach is the use of plant extract for the synthesis of metal oxides NPs. In the framework of this study, the ecofriendly MgO nanoparticles were synthesized using Acalypha Indica leaf extract,functioning as reducing and capping agent by co-precipitation method. The predecessor taken here was Magnesium Nitrate. The biologically synthesized MgO NPs were characterized by various techniques like X ray diffraction(XRD), Fourier Transform infrared spectroscopy(FTIR), Scanning electron microscope (SEM) with Energy Dispersive X-ray spectroscopy(EDX) profile and its antibacterial activity is evaluated against causative organisms. XRD studies confirmed the face centered cubic crystalline structure of MgO NPs and the average crystalline size of MgO NPs calculated using Scherer’s formula was found to be 13 nm. FTIR spectrum shows a significant Mg-O vibrational band. Purity, surface morphology and chemical composition of elements were confirmed by SEM with EDX. The SEM result shows the fine spherical morphology with the grain size range between 43nm to 62nm. Antimicrobial assay of MgO NPs was examined against gram positive and negative bacteria. Appreciated activity was observed on the Staphylococcus aureus bacterial species. In general, the renewed attempt of this facile approach gave the optimum results of multifunctional MgO NPs.

Urea hydrolysis and inorganic N in a Luvisol after application of fertiliser containing rare-earth elements

Soil Research ◽  
2003 ◽  
Vol 41 (4) ◽  
pp. 741 ◽  
Author(s):  
Xingkai Xu ◽  
Zijian Wang ◽  
Yuesi Wang ◽  
Kazuyuki Inubushi
Keyword(s):  
Rare Earth ◽  
Rare Earths ◽  
Substantial Reduction ◽  
Application Rate ◽  
Urea Hydrolysis ◽  
High Rate ◽  
Short Term ◽  
N Content ◽  
N Fertilisers ◽  
Hydrolysis Of

In recent decades, Chinese agriculturists have used rare-earth-containing fertilisers as basal fertilisers together with N fertilisers (e.g. urea). We studied urea hydrolysis and its hydrolysis products in a laboratory experiment using urea-N fertiliser with rare earths at rates from 0.5 to 50% (w/w). The results indicated that application of rare earths at a high rate could result in a short-term inhibition of urea hydrolysis and an increase in soil (NH4+ + NO3– + NO2–)-N content. When the application rate of rare earths was higher than 5% of the applied urea-N (corresponding to 10 mg/kg soil), soil exchangeable NH4+-N content increased significantly following the hydrolysis of the applied urea. Increasing the application rate of rare earths appeared to reduce the content of soil urea-derived (NO3– + NO2–)-N. A substantial reduction in soil pH was found immediately after application of rare earths and urea. We conclude that application of rare earths at >10 mg/kg may lead to a substantial increase in the content of urea-derived N in the soil, via the inhibition of urea hydrolysis and nitrification.

scholarly journals Purinergic stimulation of rat cardiomyocytes induces tyrosine phosphorylation and membrane association of phospholipase Cγ: a major mechanism for InsP3 generation

1996 ◽  
Vol 318 (2) ◽  
pp. 723-728 ◽  
Author(s):  
Michel PUCEAT ◽  
Guy VASSORT
Keyword(s):  
Tyrosine Kinase ◽  
Time Course ◽  
Kinase Inhibitor ◽  
Extracellular Atp ◽  
Rat Cardiomyocytes ◽  
Major Mechanism ◽  
Adult Rat ◽  
Hydrolysis Of ◽  
Purinergic Stimulation ◽  
Stimulation Of

Phospholipase Cγ (PLCγ) expression and activation by a purinergic agonist were investigated in adult rat cardiomyocytes. PLCγ is expressed in isolated cardiomyocytes. Stimulation of cells with extracellular ATP induces a rapid increase in membrane-associated PLCγ immunoreactivity most probably due to redistribution of the lipase from the cytosol to the membrane. The purine triggers a significant phosphorylation on tyrosine residues of a cytosolic pool of PLCγ with a time course that correlates with that of translocation. Extracellular ATP also increases intracellular Ins(1,4,5)P3 content. All these events (translocation and phosphorylation of PLCγ, InsP3 formation) are blocked by genistein, a tyrosine kinase inhibitor. The purinergic effect on both PLCγ translocation and phosphorylation are Ca-sensitive. We thus propose that the purinergic stimulation activates a non-receptor tyrosine kinase that phosphorylates PLCγ in the presence of an increased Ca level and induces PLCγ redistribution to the membrane. There, PLCγ becomes activated leading to the hydrolysis of phosphatidylinositol diphosphate and in turn Ins(1,4,5)P3 formation. This cascade of events may play a significant role in the induction of arrhythmogenesis by purinergic agonists.

Silver ion catalysis in nitric acid dissolution of Ni3S2

1987 ◽  
Vol 18 (2) ◽  
pp. 195-205 ◽  
Author(s):  
Mulak Władysława
Keyword(s):  
Nitric Acid ◽  
Silver Ion ◽  
Acid Dissolution

Spectrophotometric Method for the Microdetermination of Bendiocarb Standard Residues in Water

1988 ◽  
Vol 71 (1) ◽  
pp. 51-52
Author(s):  
Swadesh K Handa
Keyword(s):  
Nitric Acid ◽  
Spectrophotometric Method ◽  
Hydrolysis Of

Abstract A spectrophotometric method has been developed for the microdetermination of bendiocarb in water. The method is based on the reaction of bendiocarb phenol resulting from the hydrolysis of bendiocarb with nitric acid to form a yellow complex with an adsorption maximum at 420 nm. The method is applicable for estimation of residues of bendiocarb in the range of 10-100 μg/5 mL solution.

Assessment of human paraoxonase activity by electrochemistry: a simple and novel approach

2016 ◽  
Vol 8 (46) ◽  
pp. 8141-8146 ◽  
Author(s):  
Tiago Monteiro ◽  
Francisco Oliveira ◽  
Adérito Fins ◽  
Clara G. Dias ◽  
Célia M. Silveira ◽  
...  
Keyword(s):  
Paraoxonase 1 ◽  
Catalytic Hydrolysis ◽  
Electrochemical Assay ◽  
Paraoxonase Activity ◽  
Novel Approach ◽  
Hydrolysis Of

Measurement of the catalytic hydrolysis of paraoxon by human paraoxonase 1 using a simple electrochemical assay.

scholarly journals The hydrolysis of geminal ethers: a kinetic appraisal of orthoesters and ketals

2016 ◽  
Vol 12 ◽  
pp. 1467-1475 ◽  
Author(s):  
Sonia L Repetto ◽  
James F Costello ◽  
Craig P Butts ◽  
Joseph K W Lam ◽  
Norman M Ratcliffe
Keyword(s):  
Water Contamination ◽  
Jet Fuel ◽  
Computational Studies ◽  
Water Interface ◽  
H Nmr ◽  
Novel Approach ◽  
Rapid Hydrolysis ◽  
First Time ◽  
Hydrolysis Of ◽  
Hydrolysis Reactions

A novel approach to protecting jet fuel against the effects of water contamination is predicated upon the coupling of the rapid hydrolysis reactions of lipophilic cyclic geminal ethers, with the concomitant production of a hydrophilic acyclic hydroxyester with de-icing properties (Fuel Dehydrating Icing Inhibitors - FDII). To this end, a kinetic appraisal of the hydrolysis reactions of representative geminal ethers was undertaken using a convenient surrogate for the fuel–water interface (D2O/CD3CN 1:4). We present here a library of acyclic and five/six-membered cyclic geminal ethers arranged according to their hydroxonium catalytic coefficients for hydrolysis, providing for the first time a framework for the development of FDII. A combination of 1H NMR, labelling and computational studies was used to assess the effects that may govern the observed relative rates of hydrolyses.

Catalytic Hydrolysis of Hydrogen Cyanide on Cu-Al Catalyst

2015 ◽  
Vol 1094 ◽  
pp. 15-19
Author(s):  
Lin Xia Yan ◽  
Sen Lin Tian ◽  
Qiu Lin Zhang
Keyword(s):  
Calcination Temperature ◽  
Hydrogen Cyanide ◽  
Influence Factor ◽  
Ph Value ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Cu Content ◽  
Co Precipitation ◽  
The Impact ◽  
Hydrolysis Of

Cu-Al catalysts were synthesized by the co-precipitation method to study hydrolysis of hydrogen cyanide. During the synthesis, the impact of Cu/Al molar ratio, pH value and calcination temperature was investigated and the best synthesis condition was found. The results indicate that the remove of hydrogen cyanide first increases and then decreases with increasing Cu/Al molar ratio, pH value and calcination temperature, which reaches the maxima and remains above 95% at 360 min when Cu/Al molar ratio is 2:1, pH value is approximately 8.0 and calcination temperature is 400°C around. The analysis of X-ray diffraction (XRD) shows that Cu content is the main influence factor at Cu/Al molar ratio below 2:1 whereas crystallinity of catalysts is the key factor at Cu/Al molar ratio above 2:1.

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