scholarly journals Conditions for the Development of Phase Components K2CaP2O7 , KCaP3O9 in Toxic Dust

2021 ◽  
Vol 24 (3) ◽  
pp. 38-44
Author(s):  
Anar K. Zhumadilova ◽  
Elmira B. Madaliyeva ◽  
Saule Z. Zhigitova
Keyword(s):  
Phase Composition ◽  
Nitric Acid ◽  
Nutrient Content ◽  
Generation Process ◽  
Elemental Phosphorus ◽  
Dust Generation ◽  
Yellow Phosphorus ◽  
Acid Reaction ◽  
Three Stages ◽  
Main Components

The present study analyses the composition and main components of toxic dust. To develop and understand the methods of controlling the dust generation process, it is necessary to study the data that provide detailed information about the reaction mechanism. The results of studies of the phase composition of dust conducted in the laboratory and their comparison with the data obtained earlier by other authors allowed establishing a fairly reliable diagnosis of the phase composition of dust. The analysis revealed that the dust of various phosphorus plants comprises the same basic components, yet the chemical bonds between them differ. The purpose of this study, conducted in the research laboratory of the Zhambyl Branch of LLP “Kazphosphate” (NDFZ) is to investigate the possibility of using new toxic dust, as well as the toxic dust from storage tanks to obtain NPK fertilisers. The study comprises three stages of investigating the oxidation of elementary phosphorus with nitric acid, since elementary yellow phosphorus is dangerous for the environment. As a result of the 1st stage of the study, it was found that toxic dust oxidised with nitric acid cannot be used as a fertiliser, since a non-technological mass is generated, such as acid resin, which is not suitable for drying and granulation. To neutralise the acid reaction mass, it was decided to use an aqueous solution of ammonia, thereby increasing the nutrient content and obtaining a complex NPK fertiliser. In the course of the study, the authors found in the 2nd and 3nd stages of the experiment that to obtain a productsuitable for fertilisation, it is necessary to strictly control the content of elemental phosphorus in the initial toxic dust and adjust the consumption of nitric acid based on its results

Experimental Study of Purifying Precipitated Silica Produced from Yellow Phosphorus Slag

2012 ◽  
Vol 455-456 ◽  
pp. 503-506 ◽  
Author(s):  
Guo Bing Li ◽  
Hai Lin ◽  
Yan Li Ma ◽  
Yi Su
Keyword(s):  
Experimental Study ◽  
Nitric Acid ◽  
Reaction Time ◽  
Nitric Acid Concentration ◽  
Acid Leaching ◽  
Quality Requirements ◽  
Solid Ratio ◽  
Precipitated Silica ◽  
Yellow Phosphorus ◽  
Fe Content

When precipitated silica was prepared from yellow phosphorus slag by the phosphoric acid leaching, the Fe content can not meet the quality requirements of the product. This article indicates the method of purifying precipitated silica with nitric acid solution, which may decrease the Fe content to about 0.02%. The purification optimum technical conditions are: the nitric acid concentration 8%, reaction time 2.0 hours, reaction temperature 343.15K, fluid solid ratio 4:1, stirring speed 300 rpm.

Study on Degradation of Nitrobenzene in Groundwater by Fenton-Like Oxidation Based on Iron in Aquifer Materials

2011 ◽  
Vol 183-185 ◽  
pp. 516-521 ◽  
Author(s):  
Meng Sun ◽  
Yong Sheng Zhao ◽  
Jun Dong ◽  
Li Li Dong
Keyword(s):  
Hydroxyl Radical ◽  
Contaminated Sites ◽  
Contaminated Site ◽  
Generation Process ◽  
High Efficient ◽  
Good Potential ◽  
Three Stages ◽  
Radical Generation ◽  
Extraction Agent

Fenton and Fenton-like reactions are regarded as high efficient methods in advanced treatment of nitrobenzene wastewater but both restrained in degradation of nitrobenzene in groundwater because of the low pH condition( less than 4 ) requirement and other problems such as secondary pollution by the irons in contaminated sites. This paper reports a new Fenton-like technology combined irons extraction from aquifer materials which were found in a nitrobenzene contaminated site in China with hydrogen peroxide catalytic oxidation. The simulate experiments were conducted to investigate the oxidation of nitrobenzene in groundwater by this method under the condition of neutral pH and 8~10°C. The comparison of different extraction agent and production rule of hydroxyl radical were both studied in this research. The results indicated that extraction had hysteresis property because the highest extracting efficiency occurred after 36h. Extraction agent DCB has the highest efficiency, for Fe3+ was 62.92% and Fe2+ was 30.17%. The highest removal efficiency could reach 80.2% while the mole ratio of nitrobenzene to H2O2 was 1:200. Three stages could found in hydroxyl radical generation process, in the first stage hydroxyl radical generated rapidly in 0~30min, then decreased slowly between 30min and 120min, at last the generation tended to be steady after 120h. The results could possess a good potential for application in the treatment of nitrobenzene contaminated groundwater and provide theoretical basis on in-situ chemical remediation technology of nitrobenzene contaminated sites.

scholarly journals Development of a theoretical-practical script for clinical simulation

2017 ◽  
Vol 51 (0) ◽  
Author(s):  
Renata Paula Fabri ◽  
Alessandra Mazzo ◽  
José Carlos Amado Martins ◽  
Ariadne da Silva Fonseca ◽  
César Eduardo Pedersoli ◽  
...  
Keyword(s):  
Qualitative Study ◽  
Learning Process ◽  
Teaching Experience ◽  
Educational Institutions ◽  
Clinical Simulation ◽  
Data Content ◽  
Three Stages ◽  
Main Components ◽  
Simulated Scenario

Abstract OBJECTIVE To develop a theoretical-practical script based on the opinion of experts to be used in simulated clinical activities. METHOD Qualitative study through analysis of content of interviews with experts on the theme in order to develop the proposed script. Of the 24 invited experts, 12 specialists from educational institutions in Brazil and abroad participated in the study in compliance with the ethical precepts. The experts responded to questions on the characterization of their study attributes and described the items required for the development of a simulated scenario. In view of the responses obtained, data content was analyzed and classified into units and subunits of significance. RESULTS The items mentioned for the development of the script generated seven units of significance. The units and subunits of significance were gathered in three stages of the main components of the simulated scenario: prior, preparation, and finals. CONCLUSION This study enables an innovative, stimulating teaching experience, making it easier for professors to use the simulation resource as a learning process in an effective and objective manner, as a guide to professors and researchers in the area of clinical simulation.

Reaction of N-Acetyl-2,3-diphenylindole with Nitric Acid

1972 ◽  
Vol 50 (20) ◽  
pp. 3392-3396 ◽  
Author(s):  
Vinod Dave ◽  
E. W. Warnhoff
Keyword(s):  
Nitric Acid ◽  
Acid Reaction ◽  
Acid Catalyzed ◽  
Chemical Evidence

Based on spectroscopic and chemical evidence the 3-hydroxy-6-nitro-2,3-diphenylindolenine structure 8 is assigned to the previously reported N-acetyl-2,3-diphenylindole–nitric acid reaction product. The product from the acid-catalyzed rearrangement of 8 is assigned the oxindole structure 12.

scholarly journals Karakterisasi Karbon Baggase Teraktivasi dan Aplikasinya untuk Adsorpsi Logam Tembaga

2020 ◽  
Vol 7 (2) ◽  
pp. 46
Author(s):  
Dahlia Rosma Indah ◽  
Safnowandi Safnowandi
Keyword(s):  
Activated Carbon ◽  
Nitric Acid ◽  
Phosphoric Acid ◽  
Contact Time ◽  
Metal Content ◽  
Copper Metal ◽  
Waste Water Sample ◽  
Time Variations ◽  
Three Stages ◽  
The Difference

Bagasse is waste produced from the process of milking or extracting sugarcane stems. Baggase can be optimized in terms of use value and its function as an alternative technology, namely as an active carbon manufacturing material that can be used as a copper (Cu) adsorbent. This study discusses the functional baggase activated carbon group of phosphoric acid and nitric acid using Fourier Transform Infra Red (FTIR) and its application as a copper metal adsorbent in silver craft waste in Ungga Village, Praya, Central Lombok. The production of activated bagasse carbon consists of three stages, namely first dehydration by burning bagasse until it turns into carbon, the second carbonation is heating at 500ºC, carbon results are 100-200 mesh and third, activation by soaking 50 grams of carbon in 500 mL of 20% phosphoric acid and 20% nitric acid for 12 hours. After that the carbon is dried at 110ºC and finally heated at 500ºC for 1 hour. The bagasse carbon that has been made is put into 25 mL of waste water sample with a mass of 2 grams of adsorbent. Samples were then stirred at 30, 60, 90, 120 and 150 minutes contact time variations at a speed of 180 rpm using a batch system. The optimum contact time that is used to calculate the efficiency of copper metal content reduction is by calculating the difference in the metal content of copper metal before it is adsorbed and after it is adsorbed using activated carbon baggase. Concentrations of all copper metals were analyzed using Atomic Absorption Spectrophotometer (AAS). Identification using FTIR spectrophotometer shows that carbon baggase in this study contains functional groups C = O, C = C, C-C, N = O, C = N, C-OH, CH2 and C-H. From the research it was found that the copper metal content in the sample was 14.5710 ppm. The optimum contact time on copper metal adsorption is at 120 minutes contact time which results in optimum adsorption efficiency on copper metal that is 84.88%. Activated carbon baggase is an effective adsorbent to reduce levels of copper metal in silver craft waste.

scholarly journals SEARCHING OF INTERDISCIPLINARY RELATIONS BY EXPLORING THE PROCESS OF PHOTOSYNTHESIS

2014 ◽  
Vol 11 (3) ◽  
pp. 23-34
Author(s):  
Violeta Šlekienė ◽  
Loreta Ragulienė
Keyword(s):  
Science Education ◽  
Natural Science ◽  
Educational Practice ◽  
Structured Interview ◽  
Graph Tree ◽  
Interview Survey ◽  
Three Stages ◽  
Main Components ◽  
Natural Science Education ◽  
Different Levels

Science education is based on knowledge of natural sciences, such as biology, chemistry, physics and astronomy. One of the main tasks of natural science education – to be able to discover the connection between the natural science subjects, and to understand the nature processes and phenomena. Interdisciplinary science education emphasizes in general programs of basic and secondary education. Educational practice and research shows that not all science subjects’ teachers are equally prepared to use interdisciplinarity in their lessons. This analysis focuses on the searching of interdisciplinary links by experimentally exploring the phenomenon of photosynthesis. The process of photosynthesis was selected as one of the most important phenomena of nature, known and understandable for all students at different levels. In order to reveal and highlight the essential integration links of photosynthesis three stages research (an experimental exploring of photosynthesis, a semi-structured interview survey, graph-tree drawing) was carried out. Graph-tree of photosynthesis revealed as content of physics, chemistry and biology subjects are linked by integrative relations. Quite wide and deep interdisciplinary links of photosynthesis process was discerned: knowledge of each subject needed in order to properly understand and master the process of photosynthesis was shown; the main components of photosynthesis process were excluded and aspects of the development of the concept have been provided. Key words: science education, interdisciplinary relations, the process of photosynthesis, graph-tree.

Extraction of Zirconium From Iraqi Bauxite Ore

2020 ◽  
Vol 38 (10A) ◽  
pp. 1421-1429
Author(s):  
Israa A. Aziz ◽  
Moayyed G. Jalhoom ◽  
Muhanad A. Kheriallah
Keyword(s):  
Nitric Acid ◽  
Contact Time ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solid Ratio ◽  
Second Stage ◽  
Stirring Rate ◽  
Bauxite Ore ◽  
Three Stages ◽  
Hydrometallurgical Method

This research is devoted to the study of the extraction of zirconium from Iraqi Bauxite Ore by using hydrometallurgical method. The chemical analysis was done to the bauxite ore by using X-ray florescence, X-ray diffraction and atomic absorption spectroscopy. Zirconium Extraction was performed via three stages; the first stage is leaching of bauxite with sodium hydroxide for alumina leaching. The second stage is leaching of zirconium species from the remained powder produced from stage one after washing with deionized water and, nitric acid (HNO3 solutions). The results of the first stage has reflected the recovery of 42.27 % of Al2O3 which has been leached 100°C temperature, 7.5 molar of NaOH, liquid to solid ratio of 20/1, and stirring rate 450 rpm.  The highest leaching percent of zirconium (Zr%) from the red mud approached 98.48 % at 100°C temperature, 7 molar acid concentration, 120 min. contact time, solid to liquid  ratio (S/L) of 16/1, and stirring rate of 450 rpm. 99.47% recovery of zirconium was accomplished  from  nitric acid solutions by use of 3molar tri-n-butylephosphate (TBP)in kerosene at ,contact time for 6 min, and organic to aqueous phase (O/A) of 4/1.

scholarly journals Generating axial compressor maps to zero speed

2020 ◽  
pp. 095765092097605
Author(s):  
Luis E Ferrer-Vidal ◽  
Vassilios Pachidis ◽  
Richard J Tunstall
Keyword(s):  
Gas Turbines ◽  
Axial Compressor ◽  
Sensitivity Study ◽  
Generation Process ◽  
Performance Models ◽  
Start Up ◽  
Map Generation ◽  
Industrial Gas Turbines ◽  
Main Components ◽  
Aviation Engines

Gas turbine performance models typically rely on component maps to characterize engine component performance throughout the operational regime. For the sub-idle case, the lack of reliable rig test data or inability to run design codes far from design conditions entails that component maps have to be generated from the extrapolation of existing data at higher speeds. This undermines the accuracy of whole-engine sub-idle performance models, at times impacting engine development and certification of aviation engines and the accuracy of start-up performance prediction in industrial gas turbines. One of the main components driving this issue is the core compression system, which can present operability concerns during light-up and which also sets the combustor airflow required for ignition. This paper presents, discusses, and draws on previous approaches to describe a method enabling the creation of sub-idle compressor maps from analytical and physical grounds. The method relies on the calculation of zero-speed and torque-free lines to generate a map down to zero speed along with analytical interpolation. A method for the interpolation process is described. A sensitivity study is carried out to assess the effects that different elements of the map generation process may have on the accuracy of the resulting performance calculation. Overall, a method for the generation of accurate, consistent maps from limited geometry data is identified.

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