scholarly journals Fluoroammonium method for processing of cake from leaching of titanium-magnesium production sludge

2022 ◽  
Vol 320 (1) ◽  
pp. 67-74
Author(s):  
А.M. Yessengaziyev ◽  
◽  
А.A. Ultarakova ◽  
P.C. Burns ◽  
◽  
...  
Keyword(s):  
Chemical Properties ◽  
Acid Leaching ◽  
Total Content ◽  
Titanium Tetrafluoride ◽  
Sodium Aluminosilicate ◽  
Magnesium Production ◽  
Nitric Acid Leaching ◽  
Titanium Aluminum ◽  
Physical And Chemical ◽  
Hydrolysis Of

We present the results of the physical and chemical properties of cake from nitric-acid leaching of titanium production sludge. It was found that all silicon in the cake is in the form of quartz, albite, sillimanite, sodium aluminosilicate. In total, these minerals make up the majority of the cake 60.24%. Titanium is presented in the form of rutile, titanium aluminum oxide, which in total is 35.56%. Iron is part of sillimanite and hematite, the total content of which is about 4.2%. The optimal parameters of fluoroammonium processing of cake were determined: silicon distillation into sublimates at 300°С for 6 hours, sublimation of titanium in the form of titanium tetrafluoride at 800°С for 2 hours. The process of alkaline hydrolysis of sublimates of fluoride compounds and cinder was carried out. Purification of impurities and calcination of hydrated titanium dioxide were carried out. The resulting titanium and silicon dioxide products contain: 96.2% TiO2, 88 % SiО2, respectively; a niobium-containing intermediate product with a content of 11.6 % Nb2O5 was also obtained.

scholarly journals Adsorption of Copper in Soil and its Dependence on Physical and Chemical Properties

2018 ◽  
Vol 66 (1) ◽  
pp. 219-224 ◽  
Author(s):  
Vítězslav Vlček ◽  
Miroslav Pohanka
Keyword(s):  
Soil Properties ◽  
Solid Phase ◽  
Chemical Properties ◽  
Total Content ◽  
Exchange Capacity ◽  
Soil Reaction ◽  
Available Phosphorus ◽  
Copper Adsorption ◽  
Phosphorus And Potassium ◽  
Physical And Chemical

Soil samples (n = 11) were collected in the chernozem areas of the Czech Republic (the Central Europe) from the topsoil and used as representative samples. All sampling areas have been used for agricultural purposes (arable soil) and they were selected as typical representatives of agricultural soil. These samples represented the soil with same genesis (to reduction differencies between soil types) but with different soil properties (physical and chemical). Complete chemical and physical analyses were made for confirmation of copper adsorption on solid phase: we analysed the particle size distribution, content of oxidizable carbon (Cox), the cation exchange capacity (CEC), supply of exchange calcium, magnesium, sodium, phosphorus and potassium, soil reaction and the total supply of Fe, Al, Mn, Ca, Mg, K, P and N. The strongest simple correlation between analysed soil properties and copper concentration had content of available magnesium (r = 0.44) and available phosphorus (r = −0.51). In the case of multiple correlations (i. e. collective influence of multiple soil properties) had the strongest influence combination of clay, soil reaction, total content of phosphorus, available magnesium and available phosphorus. The main influence of phosphorus and magnesium is evident. We suppose that copper and phosphorus enter into specific complex. Influence of these five soil properties can explain 92.7 % (r = 0.927) changes in the content of copper changes in the experiment.

Hydrothermal Synthesis of TiO2/SiO2 Hybrid Photocatalyst from Rice Husk Ash

2007 ◽  
Vol 352 ◽  
pp. 281-285 ◽  
Author(s):  
P. Sujaridworakun ◽  
Supatra Jinawath ◽  
W. Panpa ◽  
Akira Nakajima ◽  
Masahiro Yoshimura
Keyword(s):  
Rice Husk ◽  
Rice Husk Ash ◽  
Uv Light ◽  
Porous Silica ◽  
Chemical Properties ◽  
Nano Crystalline ◽  
Ultraviolet Ray ◽  
Physical And Chemical ◽  
Hydrolysis Of ◽  
Fine Tio2

Photocatalyst materials were prepared as a hybrid between TiO2 /SiO2 via low temperature hydrothermal method (150oC) without further heat treatment. Porous silica from rice husk ash was used as a support for fine TiO2 particles which acted as a photocatalyst when radiated with a UV light. TiO2-deposited SiO2 was successfully prepared through hydrolysis of TiOSO4 solution by controlling synthesis parameters such as pH ,concentration of TiOSO4, temperature and time under hydrothermal treatment. The obtained products were characterized for physical and chemical properties by means of XRD, XRF, BET and TEM . It was found that pH had an influence on the crystallization of TiO2, and under an appropriated pH, only anatase presented along with amorphous phase. High crystallinity of nano-crystalline anatase ( about 5 nm) deposited on silica surface was observed through TEM. Adsorption and photocatalytic performances of the prepared catalyst were evaluated in methylene blue aqueous solution in the dark and under ultraviolet ray irradiation, respectively. Due to the synergetic functions of adsorption by porous substrate and decomposition by TiO2 photocatalyst, an enhancing of photocatalytic activity for decomposition of organic pollutants in water under UV rays was obtained.

scholarly journals Phosphorus resources and fractions in peat-muck soils

2018 ◽  
Vol 29 (3) ◽  
pp. 1-6
Author(s):  
Marcin Becher ◽  
Krzysztof Pakuła ◽  
Joanna Pielech ◽  
Ewa Trzcińska
Keyword(s):  
Soil Phosphorus ◽  
Chemical Properties ◽  
Total Content ◽  
Phosphorus Compounds ◽  
Organic Soils ◽  
Variable Parameters ◽  
Metallic Oxides ◽  
Physical And Chemical ◽  
Iron Manganese ◽  
Total Resource

Abstract The goal of the research was to determine the resources and speciation (forms of occurrence) of phosphorus in organic soils of drained fens of the Wysoczyzna Siedlecka. Two profiles of muck soils were generated from different peats. Basic physical and chemical properties of the soils and the quantity, resources and fractions of phosphorus in the soil were determined. The majority of the total resource of soil phosphorus was accumulated in the muck horizons of the analysed soils. The total content of phosphorus materially correlated with characteristically variable parameters in the moorshification process (voids free bulk density of the content of organic matter, C/N ratio and C/P ratio). Additionally, a material positive correlation of the content of phosphorus with the content of iron, manganese and aluminium was observed. The moorshification process of the analysed soils entails the qualitative transformation of phosphorus compounds, mainly involving an increase in the share of more labile and easily available forms, forms released in reduction conditions and forms combined with metallic oxides, apatite, carbonate and labile organic forms.

scholarly journals Polar Head Modified Phospholipids by Phospholipase D-Catalyzed Transformations of Natural Phosphatidylcholine for Targeted Applications: An Overview

Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 997
Author(s):  
Chiara Allegretti ◽  
Francesca Denuccio ◽  
Letizia Rossato ◽  
Paola D’Arrigo
Keyword(s):  
Phospholipase D ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Reaction Conditions ◽  
Chemical Methods ◽  
Polar Head ◽  
Transphosphatidylation Reaction ◽  
Physical And Chemical ◽  
Hydrolysis Of ◽  
And Chemical Properties

This review describes the use of phospholipase D (PLD) to perform the transphosphatidylation of the most common natural phospholipid (PL), phosphatidylcholine (PC) to obtain polar head modified phospholipids with real targeted applications. The introduction of different polar heads with distinctive physical and chemical properties such as charge, polarity and dimensions allows the obtainment of very different PLs, which can be exploited in very diverse fields of application. Moreover, the inclusions of a bioactive moiety in the PL polar head constitutes a powerful tool for the stabilization and administration of active ingredients. The use of this biocatalytic approach allows the preparation of compounds which cannot be easily obtained by classical chemical methods, by using mild and green reaction conditions. PLD is a very versatile enzyme, able to catalyze both the hydrolysis of PC to choline and phosphatidic acid (PA), and the transphosphatidylation reaction in the presence of an appropriate alcohol. The yield of production of the desired product and the ratio with the collateral PA formation is highly dependent on parameters such as the nature and concentration of the alcohol and the enzymatic source. The application of PLD catalyzed transformations for the production of a great number of PLs with important uses in medical, nutraceutical and cosmetic sectors will be discussed in this work.

THE EFFECT OF GLUCOAMYLASE ON VARIOUS TYPES OF STARCH IN THE NATIVE STATE

2020 ◽  
pp. 284-285
Author(s):  
Z. Borodina
Keyword(s):  
Low Temperature ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Native State ◽  
Physical And Chemical ◽  
Hydrolysis Of ◽  
And Chemical Properties

Was conducted a study of low-temperature hydrolysis of various types of starch in the native state: corn, corn amylopectin, pea, wheat and rice starches. Were establidhed different susceptibility of starches to the action of the enzyme glucoamylase, changes in the physical and chemical properties of samples after hydrolysis.

scholarly journals Surface Properties and Denitrification Performance of Impurity-Removed Rare Earth Concentrate

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 580
Author(s):  
Kai Zhang ◽  
Yuze Bai ◽  
Zhijun Gong ◽  
Zengwu Zhao ◽  
Baowei Li ◽  
...  
Keyword(s):  
Rare Earth ◽  
Photoelectron Spectroscopy ◽  
Active Sites ◽  
Chemical Properties ◽  
Acid Leaching ◽  
X Ray Diffraction ◽  
Acid Base ◽  
X Ray ◽  
Temperature Programmed ◽  
Physical And Chemical

Acid leaching and alkali roasting were used to remove impurities such as Ca and Si in Baiyun Obo rare earth concentrate. The effects of acid–base treatment on the physical and chemical properties of the samples were analyzed by scanning electron microscopy, X-ray diffraction, Brunauer–Emmett–Teller characterization, X-ray photoelectron spectroscopy, H2-temperature-programmed reduction, NH3-temperature-programmed desorption (TPD), and NO-TPD. Results showed that the content of Ce7O12 in the rare earth concentrates increased and the dispersion was uniform. The grains became smaller, the specific surface area of rare earth concentrates increased, and the active sites were more exposed. Ce coexisted in the form of Ce3+ and Ce4+, whereas Fe coexisted in the form of Fe3+ and Fe2+. The content of Fe3+ was increased. The acid–base-treated rare earth concentrates had a denitration efficiency of 87.4% at a reaction temperature of 400 °C.

scholarly journals STRONTIUM CONTENT IN SANDY SOILS IN AGRICULTURE FIELDS (CASE STUDY: MOUNDOU, CHAD)

AGROFOR ◽  
2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Kamssou KOI ◽  
Victor NAGORNY ◽  
Otilija MISECKAITE ◽  
Yuri MAZHAYSKY
Keyword(s):  
Soil Depth ◽  
Chemical Properties ◽  
Sandy Soils ◽  
Total Content ◽  
Exchange Capacity ◽  
Strontium Content ◽  
Physical And Chemical ◽  
Very High ◽  
And Chemical Properties

During evaluation of physical and chemical properties of sandy soils and theirfertility in Southern part of Republic of Chad it has been revealed that some soilshave very high content of strontium. Its content varies from 10 to 270 mg/kg ofsoil depending on type of soil, depth of soil layers, clay and organic content.Strontium content negatively correlates with total content of calcium andphosphorus in layers of soil. Low CEC (CEC - Cation-exchange capacity) of soilmay be a reason of possible translocation of strontium from higher to lower layersof soils. Strontium content in soils do not relates with level of radioactivity of soilmeasured. The highest content of strontium has been found in soils developed onsome eolian and colluvio-alluvium deposits. Some researchers hypothesize thatsome endemic and chronic diseases such as Kashin-Beck disease, `Dysostosisenchondralis endemic`, endemic hoiter, osteoarthritis might be caused by highcontent of strontium in water and plant foods contaminated with it. Absence ofconsensus on etiological factors of these diseases confirms that it is worthconsidering necessity of further studies of different affects of high content ofstrontium in water and foods on human health directly or indirectly throughcausing misbalance in mineral nutrition.

Pyridoxal phosphate as a constituent of the histaminase (benzylamine oxidase) of pig plasma

1965 ◽  
Vol 163 (990) ◽  
pp. 45-60 ◽  
Keyword(s):  
Acid Hydrolysis ◽  
Pyridoxal Phosphate ◽  
Phosphorus Content ◽  
Chemical Properties ◽  
Subsequent Treatment ◽  
Fluorescence Properties ◽  
Benzylamine Oxidase ◽  
Physical And Chemical ◽  
Hydrolysis Of ◽  
And Chemical Properties

The histaminase (‘benzylamine oxidase’) of pig plasma has recently been crystallized and a description is given of some of the physical and chemical properties of the pure preparation of the oxidase. The fluorescence of the enzyme is typical of a protein containing tryptophan. The phosphorus content is about four atoms per molecule. On enzymic hydrolysis a product has been obtained that has the fluorescence properties of a pyridoxal protein. This product gave rise on acid hydrolysis to material capable of activating the L-tyrosine apodecarboxylase of Streptococcus faecalis R in the presence of adenosine triphosphate, indicating that pyridoxal was set free in the hydrolysis. Acid hydrolysis of a solution of the crystalline enzyme and subsequent treatment with urea yielded diffusible material with the spectroscopic and fluorescence properties of pyridoxal. Using the bacterial apodecarboxylase, traces of pyridoxal phosphate and larger amounts of free pyridoxal were shown to be present. It was calculated that about 3 or 4 moles of pyridoxal were present per mole of enzyme. Together with the phosphate estimations, these observations lead to the conclusion that the oxidase contains 3 or 4 moles of pyridoxal phosphate per mole. Observations on rats maintained on a diet deficient in vitamin B 6 are in agreement with these conclusions.

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