Impurities analysis of high purity niobium in industrial production

2003 ◽  
Vol 91 (7-8-9) ◽  
pp. 33-37 ◽  
Author(s):  
Hiroaki Umezawa
Keyword(s):  
High Purity ◽  
Industrial Production

scholarly journals AVA Biochem, Pioneer in Industrial Biobased Furan Chemistry

2020 ◽  
Vol 74 (10) ◽  
pp. 776-778
Author(s):  
Stefan Krawielitzki
Keyword(s):  
High Purity ◽  
Industrial Production ◽  
Industrial Scale ◽  
Technical Grade ◽  
Food Industries ◽  
Platform Chemical ◽  
Grade 5 ◽  
Global Leader ◽  
Specialty Chemicals ◽  
Bulk Chemistry

Swiss-based AVA Biochem AG is the global leader in the industrial production and sale of the bio-based platform chemical 5-hydroxymethylfurfural (5-HMF), a renewable and non-toxic alternative to a range of petroleum-based materials. 5-HMF has a broad range of applications in the chemical, pharmaceutical and food industries. Since 2014 AVA Biochem has been producing high-purity 5-HMF for research purposes and specialty chemicals markets, as well as technical-grade 5-HMF for bulk chemistry applications. AVA Biochem's own R&D department also develops the downstream chemistry of 5-HMF and thus opens the door to biobased furan chemistry on an industrial scale.

scholarly journals Scalable Synthesis of High-Purity (R, R)-Dexmethylphenidate Free Base

2016 ◽  
Vol 8 (4) ◽  
pp. 28 ◽  
Author(s):  
Guan Wang ◽  
Dongsheng Chen ◽  
Yuanyuan Sun ◽  
Qing Cao ◽  
Bonan Li ◽  
...  
Keyword(s):  
Amino Acid ◽  
High Purity ◽  
Industrial Production ◽  
Acid Ester ◽  
Substitution Reaction ◽  
Practical Method ◽  
Amino Acid Ester ◽  
Free Base ◽  
Hydrochloride Salt ◽  
Scalable Synthesis

<p>A practical method for the preparation of high-purity (<em>R, R</em>)-dexmethylphenidate free base was developed. The method involves a substitution reaction of 2-chloropyridine and phenylacetonitrile via hydrolysis followed by hydrogenation, configuration inversion, chiral resolution, methyl esterification, and salification to give high-purity dexmethylphenidate hydrochloride. The hydrochloride salt was then neutralized by powder sodium hydroxide overnight to give dexmethylphenidate free base with over 99% purity. This method can be used for the industrial production of the dexmethylphenidate patch API, which could also be further applied for the preparation of other types of amino acid ester free bases.</p>

scholarly journals Industrial Production Method of High Purity Dialkylphosphate

1990 ◽  
Vol 39 (5) ◽  
pp. 346-350
Author(s):  
Tomihiro KUROSAKI ◽  
Norio NISHIGAWA ◽  
Akira MATSUNAGA
Keyword(s):  
High Purity ◽  
Industrial Production ◽  
Production Method

A Simple and Robust Process for Large-Scale Synthesis of 4-Methylenepiperidine Hydrochloride

2019 ◽  
Vol 16 (10) ◽  
pp. 802-806
Author(s):  
Ao Chen ◽  
Ziqian Li ◽  
Minghai Li ◽  
Keke Liu ◽  
Weimin Li ◽  
...  
Keyword(s):  
Column Chromatography ◽  
High Purity ◽  
Industrial Production ◽  
Large Scale ◽  
Antifungal Drug ◽  
The Novel ◽  
Synthetic Process ◽  
Large Scale Synthesis ◽  
Robust Process ◽  
Organolithium Reagent

4-Methylenepiperidine hydrochloride 1 is a key intermediate for synthesis of the novel antifungal drug efinaconazole 2. In this work, a simple and robust process has been developed to synthesize 4-methylenepiperidine hydrochloride 1, with a high overall yield of 99.1% at a high purity of 99.7% in a large-scale. Moreover, this synthetic process avoided the uses of organolithium reagent and column chromatography process which are not desirable for industrial production.

IPA Recycling by Hydrolysis Reaction of TDI Residue

2014 ◽  
Vol 1078 ◽  
pp. 61-64
Author(s):  
Lian Ming Zhang ◽  
Yang Dong Hu ◽  
Lian Ying Wu ◽  
Xi Wang ◽  
Zhong Min Wang
Keyword(s):  
High Purity ◽  
Industrial Production ◽  
Isophthalic Acid ◽  
Toluene Diisocyanate ◽  
Hydrolysis Reaction ◽  
Mass Ratio ◽  
Reaction Conditions ◽  
Multiple Factors ◽  
Hydrolysis Of ◽  
By Products

Thousands of tons of tar residue are gained as by-products in the production of toluene diisocyanate (TDI) using heavy solvent. It is very necessary to recycle the residue. In view of residue composition’s diversity, high purity isophthalic acid (IPA) was obtained as product by hydrolysis of diethyl isophthalate (DEIP) in the residue. Multiple factors which affected the yield of isophthalic acid were investigated. Suitable reaction conditions for industrial production were summarized: the tar residue was grinded to 100 mesh, mass ratio (NaOH: material) was 0.3:1, react in water for 3 hours at 90°C.

Preparation and Research Advance of Electronic Grade Phosphoric Acid

2014 ◽  
Vol 881-883 ◽  
pp. 70-73
Author(s):  
Bin Wang ◽  
Kang Bi Luo
Keyword(s):  
Phosphoric Acid ◽  
High Purity ◽  
Industrial Production ◽  
Direct Method ◽  
Purification Method ◽  
Oxidation Method ◽  
Advantages And Disadvantages ◽  
Yellow Phosphorus ◽  
Research Advance

The application of high purity phosphoric acid in industrial production is more and more widely used, especially electronic grade phosphoric acid, and the demand of it has risen year by year. This paper introduces the preparation and research advance of electronic grade phosphoric acid, expounds the principle, advantages and disadvantages and research advance of preparing high purity phosphoric acid by high purity phosphorus oxidation method and phosphoric acid purification method. Using hot process by direct method to prepare high purity electronic grade phosphoric acid is still the mainstream on the current, and the key of technique is the purification of yellow phosphorus and phosphoric acid.

Observations oh Nucleation and Growth of Voids in Nickel

1970 ◽  
Vol 28 ◽  
pp. 414-415
Author(s):  
J. L. Brimhall ◽  
H. E. Kissinger ◽  
B. Mastel
Keyword(s):  
High Purity ◽  
Growth Stage ◽  
Elevated Temperatures ◽  
Early Growth ◽  
Nucleation And Growth ◽  
Pure Nickel ◽  
Different Temperatures ◽  
Total Fluence ◽  
Neutron Exposure ◽  
Growth Of Voids

Some information on the size and density of voids that develop in several high purity metals and alloys during irradiation with neutrons at elevated temperatures has been reported as a function of irradiation parameters. An area of particular interest is the nucleation and early growth stage of voids. It is the purpose of this paper to describe the microstructure in high purity nickel after irradiation to a very low but constant neutron exposure at three different temperatures.Annealed specimens of 99-997% pure nickel in the form of foils 75μ thick were irradiated in a capsule to a total fluence of 2.2 × 1019 n/cm2 (E > 1.0 MeV). The capsule consisted of three temperature zones maintained by heaters and monitored by thermocouples at 350, 400, and 450°C, respectively. The temperature was automatically dropped to 60°C while the reactor was down.

Preparation and characterisation of vanadium pentoxide supported rhodium catalyst

1988 ◽  
Vol 46 ◽  
pp. 946-947
Author(s):  
A. Legrouri
Keyword(s):  
Aqueous Solution ◽  
Thermal Decomposition ◽  
Physicochemical Properties ◽  
Surface Area ◽  
Vanadium Pentoxide ◽  
High Purity ◽  
Gas Adsorption ◽  
Rhodium Catalyst ◽  
Optical Methods ◽  
Reducible Oxides

The industrial importance of metal catalysts supported on reducible oxides has stimulated considerable interest during the last few years. This presentation reports on the study of the physicochemical properties of metallic rhodium supported on vanadium pentoxide (Rh/V2O5). Electron optical methods, in conjunction with other techniques, were used to characterise the catalyst before its use in the hydrogenolysis of butane; a reaction for which Rh metal is known to be among the most active catalysts.V2O5 powder was prepared by thermal decomposition of high purity ammonium metavanadate in air at 400 °C for 2 hours. Previous studies of the microstructure of this compound, by HREM, SEM and gas adsorption, showed it to be non— porous with a very low surface area of 6m2/g3. The metal loading of the catalyst used was lwt%Rh on V2Q5. It was prepared by wet impregnating the support with an aqueous solution of RhCI3.3H2O.

High-purity Ge x-ray detectors: Sensitivity factors and usefulness

1990 ◽  
Vol 48 (2) ◽  
pp. 548-548
Author(s):  
E. B. Steel
Keyword(s):  
High Purity ◽  
High Energy ◽  
Quantitative Chemical Analysis ◽  
Detector Performance ◽  
X Ray ◽  
Detector Sensitivity ◽  
Specimen Holder ◽  
Many Instruments ◽  
Charge Resolution ◽  
Sensitivity Factors

High Purity Germanium (HPGe) x-ray detectors are now commercially available for the analytical electron microscope (AEM). The detectors have superior efficiency at high x-ray energies and superior resolution compared to traditional lithium-drifted silicon [Si(Li)] detectors. However, just as for the Si(Li), the use of the HPGe detectors requires the determination of sensitivity factors for the quantitative chemical analysis of specimens in the AEM. Detector performance, including incomplete charge, resolution, and durability has been compared to a first generation detector. Sensitivity factors for many elements with atomic numbers 10 through 92 have been determined at 100, 200, and 300 keV. This data is compared to Si(Li) detector sensitivity factors.The overall sensitivity and utility of high energy K-lines are reviewed and discussed. Many instruments have one or more high energy K-line backgrounds that will affect specific analytes. One detector-instrument-specimen holder combination had a consistent Pb K-line background while another had a W K-line background.

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