scholarly journals EXTRACTION OF PALLADIUM

2021 ◽  
pp. 67-71
Author(s):  
S.R. Mammadova ◽  

It is known that a series of organic compounds containing in molecule SH-, NH- qroups, including halogens, carboxylic acids and their derivatives, have the ability to form the innercomplex compounds under certain conditions. These compounds permit to carry out the extraction in acidic medium, that prevents the of process hydrolysis. They are not dissolved in water but are soluble in various solvents and form colored solutions and so may be used as an extractants. The main purpose of this paper is the study of palladium extraction ability for chlorinated naphthenic acids (CNA) synthesited in laboratory on the basis of industrial alkylphenols. Ammoniumacetate with various pH was used as a buffer to extract palladium from PdCl2·2H2O 0.1 mkg/ml solution. The main task for the use of inert organic compound in extraction is the selection of reagent which dissolves it but does not form any compound. With this aim the influence of different solvents on their reagent was researched. The experiments show that chloronaphthenic acid is dissolved well in organic solvents. Its solution, for example in kerosene, is light-resistant, does not hydrolyze in water, alkalis and acids. So, chloronaphthenic recomendefor palladium extraction

2021 ◽  
Vol 102 (2) ◽  
pp. 24-30
Author(s):  
S.R. Mammadova ◽  

It isknown that a series oforganiccompoundscontained in the molecule SH, NH qroups have theabilityto formtheintracomplex compounds under certain conditions. These compounds allowto carryoutthe extraction in acidic mediumandthereforepreventthehydrolysis process. They are not dissolved in water but are soluble in various solvents and form colored solutions and so may be used in extraction chemistry. The main purpose of this paper was to study the ability to extract palladium by bis-(2-hidroxyl-5-alkylbenzyl)amine, synthesized in the laboratory on the basis of industrial alkylphenols. Ammonium acetate with various pH wasused as a buffer to extract palladiumfromPdCl2·2H2O0.1 mkg/ml solution. The main task for theuse of inert organic compound in extraction is the selection of a reagent which dissolves it but does not form any compound. For this purpose the influence of different solvents on this reagent was researched. The experiments show that bis-(2-hidroxyl-5-alkylbenzyl)amine is dissolved well in organic solvents. Itssolution, for examplein kerosene, is light-resistant, does not hydrolyze in water, alkalis and acids.Thus bis-(2-hidroxyl-5-alkylbenzyl)amine may be recomended for palladium extraction.


Author(s):  
Fajar Syahputra ◽  
Mesran Mesran ◽  
Ikhwan Lubis ◽  
Agus Perdana Windarto

The teacher is a major milestone in the world of education, the ability and achievement of students cannot be separated from the role of a teacher in teaching and guiding students. Based on the Law of the Republic of Indonesia No. 14 of 2005 concerning Teachers and Lecturers, in Article 1 explained that teachers are professional educators with the main task of educating, teaching, guiding, directing, training, evaluating, and evaluating students in early childhood education through formal education, basic education and education medium. Whereas in Article 4 of the Act, it is explained that the position of teachers as professionals serves to enhance the dignity and role of teachers as learning agents to function to improve the quality of national education.Decision making is an election process, among various alternatives that aim to meet one or several targets. The decision-making system has 4 phases, namely intelligence, design, choice and implementation. These phases are the basis for decision making, which ends with a recommendation.The Preferences Selection Index (PSI) method is a rarely used decision support system method. This method is a method developed by stevanie and Bhatt (2010) to solve the Multi Criteria Decision Making (MCDM). With the right consideration, this method can be one of the tools to determine policies in decision-making systems, especially the selection of outstanding teachers. Determination of policies taken as a basis for decision making, must use criteria that can be defined clearly and objectively.Keywords: Decision Support System, PSI, Selection of Achieving Teachers


Chemosensors ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 104
Author(s):  
Hung-Yang Kuo ◽  
Wei-Riu Cheng ◽  
Tzu-Heng Wu ◽  
Horn-Jiunn Sheen ◽  
Chih-Chia Wang ◽  
...  

This paper presents the synthesis and evaluation of a carbon molecular sieve membrane (CMSM) grown inside a MEMS-fabricated μ-preconcentrator for sampling highly volatile organic compounds. An array of µ-pillars measuring 100 µm in diameter and 250 µm in height were fabricated inside a microfluidic channel to increase the attaching surface for the CMSM. The surface area of the CMSM was measured as high as 899 m2/g. A GC peak amplification factor >2 × 104 was demonstrated with gaseous ethyl acetate. Up to 1.4 L of gaseous ethanol at the 100 ppb level could be concentrated without exceeding the capacity of this microchip device. Sharp desorption chromatographic peaks (<3.5 s) were obtained while using this device directly as a GC injector. Less volatile compounds such as gaseous toluene, m-xylene, and mesitylene appeared to be adsorbed strongly on CMSM, showing a memory effect. Sampling parameters such as sample volatilities, sampling capacities, and compound residual issues were empirically determined and discussed.


Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 94
Author(s):  
Esther Borrás ◽  
Luis Antonio Tortajada-Genaro ◽  
Francisco Sanz ◽  
Amalia Muñoz

The chemical characterization of aerosols, especially fine organic fraction, is a relevant atmospheric challenge because their composition highly depends on localization. Herein, we studied the concentration of multi-oxygenated organic compounds in the western Mediterranean area, focusing on sources and the effect of air patterns. The organic aerosol fraction ranged 3–22% of the total organic mass in particulate matter (PM)2.5. Seventy multi-oxygenated organic pollutants were identified by gas chromatography–mass spectrometry, including n-alkanones, n-alcohols, anhydrosugars, monocarboxylic acids, dicarboxylic acids, and keto-derivatives. The highest concentrations were found for carboxylic acids, such as linoleic acid, tetradecanoic acid and, palmitic acid. Biomarkers for vegetation sources, such as levoglucosan and some fatty acids were detected at most locations. In addition, carboxylic acids from anthropogenic sources—mainly traffic and cooking—have been identified. The results indicate that the organic PM fraction in this region is formed mainly from biogenic pollutants, emitted directly by vegetation, and from the degradation products of anthropogenic and biogenic volatile organic pollutants. Moreover, the chemical profile suggested that this area is interesting for aerosol studies because several processes such as local costal breezes, industrial emissions, and desert intrusions affect fine PM composition.


2021 ◽  
pp. 100092
Author(s):  
Kate I. Rundle ◽  
Mahmoud S. Sharaf ◽  
Don Stevens ◽  
Collins Kamunde ◽  
Michael R. Heuvel

2021 ◽  
Vol 308 ◽  
pp. 02023
Author(s):  
Lang Du ◽  
Yue Sheng ◽  
Jianing Wang

Geomantic theory is a natural science integrating geophysics, hydrogeology, astrology, meteorology, environmental landscape science, architecture, ecology, and human life information science. Its purpose is to carefully examine and understand the natural environment, to use and transform the nature, to create a good living environment, to win the best time, place, and people, to achieve the perfect realm of the unity of nature and man. In today’s rapid economic development and social progress, how to effectively combine architectural geomantic omen with contemporary architectural design is the concrete embodiment of modern geomantic omen culture keeping pace with The Times, and is also an important subject faced by Chinese traditional culture to benefit contemporary people and promote economic development. This paper combines Chinese geomantic omen with modern architecture and discusses the site selection of modern architecture under the guidance of geomantic omen based on the current ecological environment construction. This paper studies the site selection of ecological buildings under the guidance of geomantic omen, which provides a new idea for the application of ancient geomantic omen in the future site selection of buildings. To treat Chinese geomantic culture correctly, Chinese architecture, as the carrier of Chinese culture, should inherit critically, explore its scientific essence, and use the past for the present or use it with a little modification. This paper attempts to learn from the traditional Chinese geomantic concepts, such as wind, air, sunshine, water, and so on, and apply them to the current ecological building site selection. According to the natural environment analysis, starting from the current actual environment, applying ancient geomantic in modern construction site, adjust measures to local conditions, such as mountain gives a new meaning, while retaining the maximum illumination area, environment, plant more traditional geomantic meaning, create more appropriate, good living environment, also accord with the demand of the national ecological construction. In this paper, the attitude of advancing with The Times to look at geomancy, let geomancy theory towards the direction of the development of the real society, which is the contemporary people to study geomancy, promote geomancy theory, use geomantic omen for the benefit of modern architecture of the main task.


2011 ◽  
Vol 8 (1) ◽  
pp. 91 ◽  
Author(s):  
Cécile Gaimoz ◽  
Stéphane Sauvage ◽  
Valérie Gros ◽  
Frank Herrmann ◽  
Jonathan Williams ◽  
...  

Environmental context Volatile organic compounds are key compounds in atmospheric chemistry as precursors of ozone and secondary organic aerosols. To determine their impact at a megacity scale, a first important step is to characterise their sources. We present an estimate of volatile organic compound sources in Paris based on a combination of measurements and model results. The data suggest that the current emission inventory strongly overestimates the volatile organic compounds emitted from solvent industries, and thus needs to be corrected. Abstract A positive matrix factorisation model has been used for the determination of volatile organic compound (VOC) source contributions in Paris during an intensive campaign (May–June 2007). The major sources were traffic-related emissions (vehicle exhaust, 22% of the total mixing ratio of the measured VOCs, and fuel evaporation, 17%), with the remaining emissions from remote industrial sources (35%), natural gas and background (13%), local sources (7%), biogenic and fuel evaporation (5%) and wood-burning (2%). It was noted that the remote industrial contribution was highly dependent on the air-mass origin. During the period of oceanic influences (when only local and regional pollution was observed), this source made a relatively low contribution (<15%), whereas the source contribution linked to traffic was high (54%). During the period of continental influences (when additional continental pollution was observed), remote industrial sources played a dominant role, contributing up to 50% of measured VOCs. Finally, the positive matrix factorisation results obtained during the oceanic air mass-influenced period were compared with the local emission inventory. This comparison suggests that the VOC emission from solvent industries might be overestimated in the inventory, consistent with findings in other European cities.


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