scholarly journals Zinc Recovery from Steelmaking Dust by Hydrometallurgical Methods

Metals ◽  
2018 ◽  
Vol 8 (7) ◽  
pp. 547 ◽  
Author(s):  
Piotr Palimąka ◽  
Stanisław Pietrzyk ◽  
Michał Stępień ◽  
Katarzyna Ciećko ◽  
Ilona Nejman
Keyword(s):  
Solid Phase ◽  
Sodium Hydroxide Solution ◽  
Aqueous Sodium Hydroxide ◽  
Complete Recovery ◽  
Phase Ratio ◽  
Maximum Efficiency ◽  
Test Results ◽  
Zinc Recovery ◽  
Naoh Solution ◽  
Steelmaking Dust

Hydrometallurgical recovery of zinc from electric arc furnace dust was investigated on a laboratory scale, using aqueous sodium hydroxide solution as a leaching agent. Special attention was paid to the effect of NaOH concentration, temperature and liquid/solid phase ratio on the zinc leachability. It was found that all tested factors increased the leachability, with the maximum efficiency of 88% obtained in a 6 M NaOH solution at a temperature of 80 °C and the liquid/solid phase ratio of 40. The test results confirmed the high selectivity of the zinc leaching agent. In spite of this, complete recovery of zinc from steelmaking dust has proved to be very difficult due to the occurrence of this element in the form of stable and sparingly soluble ZnFe2O4 ferrite. Purification of the solution by cementation and electrolysis gave zinc of purity 99.88% in powder form.

Contractive Force and Transformation of Microfibril with Aqueous Sodium Hydroxide Solution for Wood

Holzforschung ◽  
2000 ◽  
Vol 54 (3) ◽  
pp. 315-320 ◽  
Author(s):  
Takato Nakano ◽  
Junji Sugiyama ◽  
Misato Norimoto
Keyword(s):  
Sodium Hydroxide Solution ◽  
Heating Temperature ◽  
Alkali Treatment ◽  
Twist Angle ◽  
Aqueous Sodium Hydroxide ◽  
Picea Jezoensis ◽  
Longitudinal Contraction ◽  
Aqueous Sodium Hydroxide Solution ◽  
Naoh Solution ◽  
Tangential Directions

Summary The mechanism of longitudinal contraction of Yezo spruce (Picea jezoensis Carr.) during treatment with aqueous NaOH solution is discussed. The contraction of wood samples increased with an increase in the concentration of NaOH solution and in heating temperature. Measurements of the stress relaxation and the twist angle during the alkali treatment showed that the alkali treatment caused the contractive and twist forces of a tracheid cell wall in longitudinal and tangential directions, depending on the components of contractive force. The temperature dependence of the contraction and the thermodynamics led to the conclusion that the longitudinal contraction of samples is due to that of microfibrils via an entropy-elastic force.

Instant Microwave Synthesis of Titania Nanoflowers for Application in DSSCs

2015 ◽  
Vol 1119 ◽  
pp. 14-18
Author(s):  
Sofia Javed ◽  
Muhammad Aftab Akram ◽  
Mohammad Mujahid
Keyword(s):  
Titanium Dioxide ◽  
Hydrofluoric Acid ◽  
Sodium Hydroxide Solution ◽  
Dye Sensitized Solar Cells ◽  
Aqueous Sodium Hydroxide ◽  
Environment Friendly ◽  
Aqueous Sodium Hydroxide Solution ◽  
Dye Sensitized ◽  
Aqueous Conditions ◽  
Sensitized Solar Cells

Nanoflowers are desirable in light driven applications like Dye Sensitized Solar Cells (DSSCs) due to their large surface area and greater light absorption capabilities. An instant, simple, cheap and environment friendly method of preparing titanium dioxide nanoflowers is presented. The nanoflowers are produced in a time as short as 5 minutes in aqueous conditions without the use of hazardous hydrofluoric acid or organic surfactants at 1 atm. pressure and low temperature of 100°C. Titanium dioxide commercial nanopowders are treated with microwaves in an aqueous sodium hydroxide solution for small durations. The resulting powders are annealed at 450°C in air and characterization is performed using XRD, SEM and Raman spectroscopy.

scholarly journals Disposition of MDMA and Metabolites in Human Sweat Following Controlled MDMA Administration

2009 ◽  
Vol 55 (3) ◽  
pp. 454-462 ◽  
Author(s):  
Allan J Barnes ◽  
Bruno S De Martinis ◽  
David A Gorelick ◽  
Robert S Goodwin ◽  
Erin A Kolbrich ◽  
...  
Keyword(s):  
Solid Phase ◽  
Random Order ◽  
Research Unit ◽  
Sweat Test ◽  
Test Results ◽  
Double Blind ◽  
Scientific Database ◽  
Sweat Testing ◽  
Clinical Research Unit ◽  
Sweat Tests

Abstract Background: Understanding the excretion of 3,4-methylenedioxymethamphetamine (MDMA) and metabolites in sweat is vital for interpretation of sweat tests in drug treatment, criminal justice, and workplace programs. Methods: Placebo, low (1.0 mg/kg), and high (1.6 mg/kg) doses of oral MDMA were given double-blind in random order to healthy volunteers (n = 15) with histories of MDMA use. Participants resided on the closed clinical research unit for up to 7 days after each dose. Volunteers wore PharmChek® sweat patches (n = 640) before, during, and after controlled dosing. Patches were analyzed by solid phase extraction and GC-MS for MDMA, methylenedioxyamphetamine (MDA), 4-hydroxy-3-methoxyamphetamine (HMA), and 4-hydroxy-3-methoxymethamphetamine (HMMA). Limits of quantification (LOQ) were 2.5 ng/patch for MDMA and 5 ng/patch for HMA, HMMA, and MDA. Results: MDMA was the primary analyte detected in 382 patches (59.7%), with concentrations up to 3007 ng/patch. MDA was detected in 188 patches (29.4%) at <172 ng/patch, whereas no HMMA or HMA was detected; 224 patches (35.0%) and 60 patches (9.4%) were positive for MDMA and MDA, respectively, at the 25-ng/patch threshold proposed by the Substance Abuse and Mental Health Services Administration. Conclusions: Sweat testing was shown to be an effective and reliable method for monitoring MDMA use in this controlled MDMA administration study. However, variability in sweat excretion suggests that results should be interpreted qualitatively rather than quantitatively. These data provide a scientific database for interpretation of MDMA sweat test results.

Cleavage Reactions of 5-Arylazo Derivatives of 1-Methyl-2-benzyl-2-imidazolin-4-ones

1975 ◽  
Vol 30 (7-8) ◽  
pp. 603-605 ◽  
Author(s):  
Nazmi Abdel Latif Kassab ◽  
Abdel Hamid Harhash ◽  
Sanna Osman Abd Allah
Keyword(s):  
Sodium Hydroxide Solution ◽  
Aqueous Sodium Hydroxide ◽  
The Other ◽  
Ring Cleavage ◽  
Prolonged Heating ◽  
Aqueous Sodium Hydroxide Solution ◽  
Aqueous Sodium ◽  
Triazine Derivatives ◽  
Cleavage Reactions ◽  
Derivatives Of

The 5-arylazo-1-methyl-2-benzyl-2-imidazolin-4-ones (1 a-c) undergo ring cleavage with 1% aqueous sodium hydroxide solution affording α-arylhydrazono-phenacetyl-sarcosine amide (2). Prolonged heating of 1 and 2 with the same reagent yields the cyanamide (3). On the other hand, when 1 a-c were refluxed with acetic acid the triazinones (4) were obtained. The latter adds one mole of Grignards reagent to yield the 5-hydroxy-1,2,4-triazine derivatives (5).

Corrosion inhibition of aluminum type 6061 Al-15 vol. pct. SiC(p) composite in 0.5-M sodium hydroxide solution by 4-amino-5-phenyl-4H-1,2,4-triazole-3-thiol

2014 ◽  
Vol 61 (4) ◽  
pp. 241-249 ◽  
Author(s):  
Reena Kumari P.D. ◽  
Jagannath Nayak ◽  
A. Nityananda Shetty
Keyword(s):  
Sodium Hydroxide ◽  
Corrosion Inhibition ◽  
Electrochemical Impedance ◽  
Sodium Hydroxide Solution ◽  
Base Alloy ◽  
Activation Parameters ◽  
Spectroscopic Techniques ◽  
Content Type ◽  
Naoh Solution ◽  
Inhibition Property

Purpose – The purpose of this paper is to report the studies on the corrosion inhibition property of 4-amino-5-phenyl-4H-1,2,4-triazole-3-thiol (APTT) for the corrosion of 6061 Al-15 vol. pct. SiC(p) composite. Design/methodology/approach – The corrosion behavior of 6061 Al-15 vol. pct. SiC(p) composite was studied at different temperatures in 0.5-M sodium hydroxide (NaOH) solution in the presence of APTT by potentiodynamic polarization (PDP) and electrochemical impedance spectroscopic techniques. The effect of inhibitor concentration and temperature on the inhibitor effect of APTT was studied. The surface morphology of the metal surface was investigated by scanning electron microscopy. The activation parameters for the corrosion of the composite and base alloy, as well as the thermodynamic parameters for the adsorption of APTT on the composite and alloy surfaces, were calculated. Findings – The inhibition efficiency of APTT increases with the increase in the concentration of the inhibitor and decreases with the increase in temperature. The adsorption of APTT on the composite was found to be through physisorption, obeying Langmuir’s adsorption isotherm. APTT acts as a mixed inhibitor with predominant cathodic action on the composite. Practical implications – APTT can be used as an inhibitor for the corrosion of 6061 Al-15 vol. pct. SiC(p) composite in the NaOH medium. Originality/value – This paper provides information regarding the corrosion inhibition property of APTT on 6061 Al-15 vol. pct. SiC(p) composite. An attempt was made to explain the mechanism of the inhibition action by APTT.

scholarly journals PEMBUATAN SUMBER RADIASI GAMMA 137Cs DENGAN AKTIVITAS 20 mCi DARI PEB U3Si2-Al PASCA IRADIASI DALAM CONTAINER STAINLESS STEEL

2016 ◽  
Vol 21 (3) ◽  
Author(s):  
Aslina Br. Ginting ◽  
Yanlinastuti Yanlinastuti ◽  
Noviarty Noviarty ◽  
Boybul Boybul ◽  
Arif Nogroho ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Gamma Radiation ◽  
Cation Exchange ◽  
High Activity ◽  
Radiation Source ◽  
Solid Phase ◽  
Test Results ◽  
Spent Fuel ◽  
Post Irradiation ◽  
Outer Capsule

PEMBUATAN SUMBER RADIASI GAMMA ISOTOP 137Cs DENGAN AKTIVITAS 20 mCi DARI PEB U3Si2-Al PASCA IRADIASI DALAM CONTAINER STAINLESS STEEL. Kegiatan uji pasca iradiasi pelat elemen bakar (PEB) U3Si2-Al banyak menghasilkan larutan dengan keaktifan yang sangat tinggi. Larutan tersebut mengandung isotop 137Cs, uranium serta transuranium yang mempunyai waktu paroh panjang dan berbahaya bagi lingkungan. Namun larutan tersebut memiliki nilai ekonomis tinggi karena dapat dimanfaatkan sebagai bahan baku untuk pembuatan sumber radiasi sinar gamma isotop 137Cs. Hal ini dapat membantu bidang industri dalam memenuhi kebutuhan sumber radioaktif dalam negeri karena selama ini kebutuhan isotop 137Cs di Indonesia masih tergantung dari industri luar negeri. Selain itu, pengadaan dan transportasi isotop 137Cs dari luar negeri serta dalam penggunaannya memerlukan persyaratan yang cukup ketat dari Badan Pengawas Tenaga Nuklir Nasional (BAPETEN), sehingga menyebabkan harga isotop 137Cs menjadi mahal sampai di Indonesia. Dengan alasan tersebut, BATAN sebagai lembaga litbang nuklir di Indonesia perlu mempelajari pembuatan sumber radiasi gamma isotop 137Cs dari larutan hasil pengujian bahan bakar nuklir U3Si2-Al pasca iradiasi. Manfaat isotop 137Cs sangat luas antara lain digunakan dalam menganalisis sampel lingkungan, industri migas, konstruksi, radiografi, perikanan, rumah sakit dan pertambangan. Pembuatan sumber radiasi gamma isotop 137Cs dimulai dari pengumpulan larutan hasil pengujian PEB U3Si2-Al. Larutan larutan hasil pengujian mengandung isotop 137Cs dan isotop lainnya dikumpulkan menjadi satu dalam botol dengan volume 65 mL. Pemisahan isotop 137Cs dari hasil fisi lainnya dilakukan dengan metode penukar kation menggunakan zeolit Lampung dengan berat 45 gr. Hasil pemisahan diperoleh 137Cs-zeolit dalam fasa padat dan isotop lainnya berada dalam fasa cair. Padatan137Cs-zeolit kering kemudian kemudian ditimbang dan diukur aktivitasnya menggunakan spektrometer-g. Hasil analisis dengan spektrometer-g diperoleh aktivitas padatan 137Cs-zeolit sebesar 20 mCi. Untuk menjadi sumber radiasi gamma 137Cs, padatan 137Cs-zeolit dengan aktivitas 20 mCi dikemas dengan cara memasukkan ke dalam inner-outer capsule terbuat dari stainless steel yang telah dirancang sebelumnya. Container stainless steel diproses menjadi sumber radiasi gamma tertutup (shield source) untuk selanjutnya disertifikasi oleh PTKMR-BATAN sebagai lembaga kalibtrator bahan radioaktif di BATAN.Kata kunci: Larutan proses PEB U3Si2-Al, radioaktif gamma, isotop 137Cs, penukar kation, zeolit Lampung dan container. MANUCFACTURING OF 137Cs GAMMA RAY SOURCE WITH ACTIVITY 20 mCi FROM PEB U3Si2-Al POST IRRADIATION IN STAINLESS STEEL CONTAINER. In the post-irradiation examination of fuel element plate (PEB) U3Si2-Al), a solution of high activity as a result of testing nuclear fuel stored in hotcell with enough volume. The solution can not be discarded as waste because it still contains fission isotop such as137Cs, uranium and transuranium, which has a long half life and dangerous for the environment. This can help the industry in order to fulfill the needs of a radioactive source in Indonesia, because until now 137Cs isotope is derived from foreign industries. In addition, the procurement and transportation of isotopes 137Cs require stringent requirements, because they have toget permission from the National Nuclear Energy Agency (BAPETEN), thus causing the price of high activity 137Cs isotopes becomes expensive to Indonesia. For these reasons, BATAN as nuclear R&D institutions in Indonesia need to study make isotopes 137Cs gamma radiation source, which is contained in the waste from spent fuel test results U3Si2-Al. Isotope 137Cs can be used very widely, such as in the analysis of environmental samples, the oil and gas industry, construction, radiography, fisheries, hospitals, and mining. Making isotope 137Cs gamma radiation source starting from the collection of waste from the test results PEB U3Si2- Al. Waste solution was collected in a bottle with volume 65 mL. Collection of 137Cs isotopes of other fission carried out using the method of cation exchange with weight 45 gr of zeolite Lampung. The results of separation are 137Cs-zeolite in the solid phase and the other isotopes are in the liquid phase. 137Cs-zeolite solid is then dried and then weighed and measured its activity using a spectrometer-g. Result of analisys by spectrometer-g was obtained acitivity of 137Cs-zeolite solids was 20 mCi.137Cs-zeolite solids then packed in sealed containers (shield source) capsule-shaped stainless steel and than certificate by PTKMR-BATAN.Keywords: Process wastle of PEB U3Si2-Al, gamma radioactive, isotope 137Cs, cation exchange, zeolite Lampung and container.

scholarly journals High-Performance Method of Recovery of Metals from EAF Dust—Processing without Solid Waste

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6061
Author(s):  
Stanisław Małecki ◽  
Krzysztof Gargul ◽  
Marek Warzecha ◽  
Grzegorz Stradomski ◽  
Artur Hutny ◽  
...  
Keyword(s):  
Solid Waste ◽  
High Performance ◽  
Coal Dust ◽  
Iron Alloy ◽  
Waste Minimization ◽  
Zinc Recovery ◽  
Ecological Requirements ◽  
Eaf Dust ◽  
Input Material ◽  
Steelmaking Dust

A highly effective method of the processing of steelmaking dust in an arc-resistant furnace has been presented. The aim of the research was to investigate the possibility of processing steelmaking dust in terms of waste minimization and selective recovery of valuable components. For this purpose, an electric arc resistance furnace was used. Granulated steelmaking dust with reducer (coal dust) was the input material. The products of the process are zinc oxide, iron alloy and slag, with properties meeting high ecological requirements. The technology does not generate solid waste. Zinc recovery is over 99% and iron recovery over 98%. The content of heavy metals (Zn + Pb + Cu) in glassy slag is below 0.2%, which ensures very low leachability.

Regeneration Effect of Fluoride-Rich Granular Activated Alumina on Desorption Regent NaOH Solution

2013 ◽  
Vol 316-317 ◽  
pp. 653-656
Author(s):  
Bai Jie Niu ◽  
Wen Ming Ding ◽  
Dan Dang
Keyword(s):  
Adsorption Capacity ◽  
Sodium Hydroxide Solution ◽  
Fluoride Concentration ◽  
Column Experiment ◽  
Fluoride Removal ◽  
Activated Alumina ◽  
Optimal Method ◽  
Column Adsorption ◽  
Naoh Solution ◽  
Regeneration Effect

As an effective adsorbent, granular activated alumina (GAA) has been widely used in defluoridation. In order to reduce cost and operate environment-friendly, the adsorbent should be regenerated. In this paper, column experiment was done to characterize the fluoride removal properties and to develop an optimal method to regenerate fluoride-rich modified activated alumina (MGAA). The MGAA can be regenerated by utilizing sodium hydroxide solution desorption, deionized water washing and ferric sulfate reactivation and then used for futher defluoride operation. The influence of the concentration of desorption agent (NaOH solution) and desorbing time on desorption rate and the adsorption capacity of regenerated MGAA were studied. The optimal desorption condition was: 1% NaOH solution for desorption agent, desorbing time in 1.5h.In addition, when the regenerated MGAA was used again for column adsorption test, its adsorption capacity reached 94% of that of original sorbent in 1mg/L outlet fluoride concentration.

Serodiagnosis of viral hepatitis A by a modified competitive binding radioimmunoassay for immunoglobulin M anti-hepatitis A virus

1979 ◽  
Vol 9 (1) ◽  
pp. 120-127
Author(s):  
D W Bradley ◽  
H A Fields ◽  
K A McCaustland ◽  
J E Maynard ◽  
R H Decker ◽  
...  
Keyword(s):  
Immunoglobulin G ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Solid Phase ◽  
Protein A ◽  
Competitive Binding ◽  
Immunoglobulin M ◽  
Test Results ◽  
Solid Phase Radioimmunoassay ◽  
Viral Hepatitis A

A competitive binding radioimmunoassay (CBA) for antibody to hepatitis A virus (HAV) was evaluated and compared with a standard solid-phase radioimmunoassay for anti-HAV, CBA was found to be sensitive and specific for the detection of anti-HAV, as demonstrated by the 98% concordance of CBA and solid-phase radioimmunoassay test results. The standard CBA test was modified for the differential detection of acute (immunoglobulin M) and convalescent (immunoglobulin G) anti-HAV by incorporation of a step in which immunoglobulin G anti-HAV was preferentially absorbed with S. aureus cells (protein A). The modified CBA test was shown to be capable of differentiating between acute- and convalescent-phase sera. The modified CBAM test was able to detect immunoglobulin M anti-HAV up to approximately 4 weeks after the onset of illness.

Sign in / Sign up

Export Citation Format

Share Document