The effect of temperature and addition of reducing agent on sodium stannate preparation from cassiterite by the alkaline roasting process

2018 ◽  
Author(s):  
Latifa Hanum Lalasari ◽  
Lia Andriyah ◽  
Tri Arini ◽  
F. Firdiyono
Keyword(s):  
Reducing Agent ◽  
Effect Of Temperature ◽  
Roasting Process ◽  
Sodium Stannate

scholarly journals Effects of reducing reagents and temperature on conversion of nitrite and nitrate to nitric oxide and detection of NO by chemiluminescence

1997 ◽  
Vol 43 (4) ◽  
pp. 657-662 ◽  
Author(s):  
Fan Yang ◽  
Eric Troncy ◽  
Martin Francœur ◽  
Bernard Vinet ◽  
Patrick Vinay ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Reducing Agents ◽  
Reducing Agent ◽  
Effect Of Temperature ◽  
Fixed Amount ◽  
Increased Temperature

Abstract To measure the concentration of nitrites and nitrates by chemiluminescence, we examined the efficiency of five reducing agents [V(III), Mo(VI) + Fe(II), NaI, Ti(III), and Cr(III)] to reduce nitrite (NO2−) and (or) nitrate (NO3−) to nitric oxide (NO). The effect of each reducing agent on the conversion of different amounts of NO2− and (or) NO3−(100–500 pmol, representing concentrations of 0.4 to 2 μmolar) to NO was determined at 20 °C for NO2− and at 80 °C for NO3−. The effect of temperature from 20 to 90 °C on the conversion of a fixed amount of NO2− or NO3− (400 pmol or 1.6 μmolar) to NO was also determined. These five reducing agents are similarly efficient for the conversion of NO2− to NO at 20 °C. V(III) and Mo(VI) + Fe(II) can completely reduce NO3− to NO at 80 °C. NaI and Cr(III) were unable to convert NO3− to NO. Increased temperature facilitated the conversion of NO3− to NO, rather than that of NO2− to NO. We evaluated the recovery of NO2− and NO3− from plasmas of pig and of dog. Recovery from plasma of both animals was reproducible and near quantitative.

scholarly journals SISTEM PENGENDALIAN SUHU DAN PEMANTAUAN KELEMBABAN BIJI KOPI PADA MESIN PENYANGRAI BERBASIS ARDUINO 2560

2017 ◽  
Vol 19 (2) ◽  
pp. 19
Author(s):  
Anggi Permana ◽  
Iman Setiono
Keyword(s):  
Liquid Crystal Display ◽  
Effect Of Temperature ◽  
Coffee Bean ◽  
Heat Element ◽  
Modern Times ◽  
Roasting Machine ◽  
Coffee Beans ◽  
Roasting Process ◽  
The Right ◽  
Gas Stoves

Anggi Permana, Iman Setiono, in this paper explain that along with the development of modern times. Technological advancements were increasingly found in manufacturing products, everything was done to be easy and practical. These products are made with the aim of helping human work. However, not all manufacturing products are automated. Some products still work manually. Therefore, we are required to be able to innovate by changing the manual process with a more efficient method by using products that are automatic. One tool is the roasting machine for coffee beans. Currently on the market it is rare for automatic coffee roasters to be designed. Most coffee roasters are done manually, use hand mixers, and use wood stoves or gas stoves. This situation becomes less efficient where the roasting is still using the hands, causing it to ripen evenly and burn. Though to get the right coffee is from the roasting process. Roasting determines the color and variety of flavors of coffee to be consumed. The effect of temperature and time also affects the results of roasting, even when roasting here we monitor the thickness of coffee beans. to produce good roasting. The principle is to give the right amount of time and the right temperature so that coffee will not only have a fragrant aroma but also create the right taste. To solve the problem, in this article we made coffee bean roasters. This coffee bean roasting system is based on Arduino MEGA type 2560. The roasting process uses the mlx90614 sensor and DHT11 sensor to monitor the moisture of coffee beans that will be displayed on the 7-segment. The heating media used is using heat elements instead of stoves. This tool is able to roast as much as 400 grams of coffee. It is expected that the roasting machine of coffee beans will be more optimal  Keywords: Arduino MEGA, heat element, DHT11 sensor, MLX90614 sensor and, 7-segment. ReferencesMusbikhin. 2011. Penegertian sensor dan macam-macam sensor. (http://www.musbikhin.com/pengertian-sensor-dan-macam-macam-sensor). diakses tanggal 4 juni 2017.Ardy, faisal. 2016. Pengertian DHT11. (https://docslide.net/documents/2012-2-00944-sk-bab2001pdf.html). diakses tanggal 4 juni 2017.Elok, Dhinda. 2016. Aplikasi Arduino Untuk Monitoring Dan Setting Suhu Piringan Logam Dengan Sensor MLX90614 Pada Aplikasi Pemanas Roti. Tugas Akhir. Tidak diterbitkan. PSD III Teknik Elektro Universitas Diponegoro, Semarang.Ecadio. 2017. Teori arduino. (http://ecadio.com/belajar-dan-mengenal-arduino-mega). diakses tanggal 30 april 2017.Syahwil, muhammad. 2017. Panduan Mudah Balajar Arduino Menggunakan Simulasi Proteus. Andi Offset. jakartaKho, Dickson. 2017. Pengertian 7segment. (http://teknikelektronika.com/pengertian-seven-segment-display-layar-tujuh-segmen/). diakses tanggal 2 mei 2017.Permata, Redi. (2016). Rancang Bangun Sistem Pengontrol BATCH MIXER Pada Industri Minuman Dengan Metode PID Berbasis Arduino Uno R3. Tugas Akhir. Tidak diterbitkan. PSD III Teknik Elektro Universitas Diponegoro, Semarang.Restiawan, Masde. (2016). Otomatisasi Pengatur Suhu Dan Waktu Pada Penyangrai Kopi ( Roaster Coffee ) Berbasis Atmega 16 Pada Tampilan Lcd ( Liquid Crystal Display). Tugas Akhir. Tidak diterbitkan. PSD III Teknik Elektro Universitas Diponegoro, Semarang.

Kinetic Mechanism on Synthesis of Copper Nanoparticle from Reduction Reaction - Effect of Temperature

2015 ◽  
Vol 754-755 ◽  
pp. 1012-1016
Author(s):  
Noorsuhana Mohd Yusof ◽  
Junaidah Jai ◽  
Ahmad Hafizie Zaini ◽  
Nur Hashimah Alias ◽  
Nurul Aimi Ghazali ◽  
...  
Keyword(s):  
Copper Nanoparticles ◽  
Room Temperature ◽  
Low Cost ◽  
Copper Nitrate ◽  
Kinetic Mechanism ◽  
Reduction Reaction ◽  
Reducing Agent ◽  
Effect Of Temperature ◽  
Hydroxyl Groups ◽  
Copper Nanoparticle

Copper nanoparticles, due to their interesting properties, low cost preparation and many potential applications in catalysis, cooling fluid or conductive inks, have attracted a lot of interest in recent years. In this study, copper nanoparticles were synthesized through the palm leaves extract that act as reducing agent. In this synthesis route, the hydroxyl groups of the polyphenols in palm extract are capable to act as reducing agent for reduction reaction. The effect of temperature given starting with control parameters at room temperature proceeds to 40, 50, 60, 70 and 80°C with the time length of 2 hours and 10 milimol copper nitrate aqueous solution. Characterization had been conducted using the instrument of UV-vis spectrophotometer, FTIR and ESEM. The average size of all powder nanoparticles was found to 109, 86, 196, 133, 241, and 230nm accordingly from room temperature till 80°C. The correspondence analysis of the results yielded that the optimum temperature was at 40°C which is 86nm of average copper nanoparticle size.

Effect of Temperature on the Quality of City Sewage Sludge Shale Brick Products

2013 ◽  
Vol 790 ◽  
pp. 316-319
Author(s):  
Bing Zhang Huang ◽  
Xi Qiang Li ◽  
Ji Zhen Zhu ◽  
Bang Biao Huang ◽  
Hai Long Wu ◽  
...  
Keyword(s):  
Sewage Sludge ◽  
Product Quality ◽  
Effective Means ◽  
Raw Material ◽  
Effect Of Temperature ◽  
Firing Process ◽  
Quality Of Protection ◽  
Roasting Process ◽  
Cooling Phase

[Objective] Research on city sewage sludge shale brick in the firing process of crack formation reason, control cracks in the firing process of the brick body, thereby improving the brick product quality, summed up the law of temperature on product quality of city sewage sludge shale brick.[Methods] In order to shale and city sludge as raw material by make bricks, drying and sintering procedure different, to analyze the reason of brick in the process of drying cracks and cracks during the roasting process.[Results] The experimental results show that in the stage of drying and preheating stage if rising too quickly, the sharp increase in the number of brick cracks, resulting in a significant decline in the quality of the finished brick. During the cooling phase if the cooling too quickly, also will increase the number of cracks, leading to reduced quality of brick.[Conclusion] Have an important influence on city sewage sludge shale formation temperature cracks, the control of the temperature is not only reasonable will prevent the formation of crack, but also an effective means to improve the quality of protection brick.

scholarly journals Analysis of temperature control effect in fluidized bed coffee roaster

2020 ◽  
Vol 14 (2) ◽  
pp. 255-263
Author(s):  
Diego Andrés Campo-Ceballos ◽  
Kevin Jancarlo Barco-Sotelo ◽  
Hector Fabian Dorado-Ipia ◽  
Carlos Alberto Gaviria-López
Keyword(s):  
Fluidized Bed ◽  
Temperature Control ◽  
Turning Point ◽  
Agricultural Sector ◽  
Effect Of Temperature ◽  
Control Effect ◽  
Grain Moisture ◽  
Roasting Process ◽  
Fluid Bed ◽  
Digital Manufacture

One of the main sources of economic income in Colombia's agricultural sector is the marketing of coffee with a high contribution to the country's economy. However, trends in coffee industry 4.0 show that the coffee roasting process is where more value aggregation is presented and at the same time is one of the most complex because multiple factors are involved such as grain moisture, volume, variety and heat and mass transfer variables. The main objective of this work was to design and implement a fluidized bed system for the study of the effect of temperature control on the physical properties of roasted coffee from Cauca-Colombia. The development of the work was addressed in 4 sequential phases: CAD design, Digital manufacture, temperature control design and the systems analysis. The proposed fluid bed system features a control system for the RoR (rate of rise) that can be adjusted between 3 to 20°C/min, and provide a prediction in the events of the standard roasting profile (Turning Point, Yellow, First Crack, Development time, Second Crack, Drop).

The Effect of Temperature on Gelation Time for Polyacrylamide/Chromium (III) Systems

1982 ◽  
Vol 22 (04) ◽  
pp. 463-471 ◽  
Author(s):  
Deborah S. Jordan ◽  
Don W. Green ◽  
Ronald E. Terry ◽  
G. Paul Willhite
Keyword(s):  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Reaction Rate ◽  
Gelation Time ◽  
Reducing Agent ◽  
Effect Of Temperature ◽  
Sweep Efficiency ◽  
Temperature Range ◽  
Production Wells ◽  
Low Efficiency

Abstract Gelled polymers are being applied to modify the movement of injected fluids in the vicinity of injection and production wells in secondary and enhanced oil-recovery projects. One approach to gelation is to form a bulk gel in situ by injecting a slug of a polyacrylamide polymer solution containing chromium (VI) followed by a polymer slug containing a reducing agent such as sodium bisulfite. Upon mixing, CR(VI) is reduced to Cr(III), and in the subsequent reaction a gel is formed. The gelation time controls the volume of fluid that can be injected in the treatment and thus is an important variable in the process. Gelation time is known to be a function of the concentration of the reactants (chromium ion, reducing agent, and polymer) as well as the polymer type, and some data relating these variables to gelation time have been reported. Another variable affecting the reaction rate is temperature, but no data relating gelation time and temperature have been published. The purposes of the work described in this paper were to obtain experimental data on the effect of temperature on gelation time for typical polyacrylamide/Cr(III) gel systems over the range of temperatures commonly encountered in reservoirs and to develop a method of correlating the data. Gelation times were measured for five different polymers, including polymers with various degrees of hydrolysis and polymers with nonionic, anionic, and cationic character. The temperature range was 25 to 80 deg. C. Polymer, metal ion, and redox system concentrations and salinity also were varied. It was determined that, for a given polymer-reducing agent system at a specified concentration, the gelation time decreases as temperature is increased. The data were correlated in a manner analogous to the Arrhenius method of correlating chemical reaction rate data. That is, plots of the logarithm of gelation time vs. the reciprocal of the absolute reaction temperature were linear over the temperature range studied. By use of a simple nth-order reaction rate model, the slope of the Arrhenius-type plot was related to activation energy. These activation energies were found to vary only slightly for the polymer systems and concentrations investigated. The results have direct application in the design of gel treatments for injection or production wells. The correlation method provides a way of predicting the effect of temperature on the time required for a given system to gel. It is recognized that in field applications factors beyond the scope of data taken in this paper may affect the gelation process. Introduction The volumetric sweep efficiency of a secondary or enhanced oil-recovery process is a major factor in determining the amount of oil recoverable by that process. In waterflooding, low efficiency results in high WOR's that lead to high operating costs in handling produced water relatively early in a project. When the WOR becomes high enough that the project is no longer economically justified, the process is terminated, and a significant amount of oil may be left unrecovered. In enhanced oilrecovery methods that involve the injection of expensive chemicals, low efficiency is even more costly. Economics may not justify the initiation of such a treatment if the expected efficiency is not sufficiently high. Reservoir heterogeneity is the primary reason for poor sweep efficiency. Particularly common are permeability variations in the vertical direction. The injected fluids tend to flow in the zones of higher permeability, bypassing the oil in the tighter zones if the permeability differences are significant. The resulting low sweep efficiency could be improved if the high permeabilities could be reduced. SPEJ P. 463^

scholarly journals Effect of Quartz on the Preparation of Sodium Stannate from Cassiterite Concentrates by Soda Roasting Process

Minerals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 605
Author(s):  
Yuanbo Zhang ◽  
Benlai Han ◽  
Zijian Su ◽  
Xijun Chen ◽  
Manman Lu ◽  
...  
Keyword(s):  
Mole Fraction ◽  
Silicon Content ◽  
Ph Value ◽  
Phase Evolution ◽  
Conversion Ratio ◽  
Roasting Process ◽  
Value Range ◽  
Sodium Stannate ◽  
Roasting Temperature ◽  
Co2 Atmosphere

Sodium stannate (Na2SnO3) has been successfully prepared by a novel process of roasting cassiterite concentrates and sodium carbonate (Na2CO3) under CO–CO2 atmosphere, namely soda roasting-leaching process. However, more than 22 wt. % tin of the cassiterite was not converted into Na2SnO3 and entered the leach residues. Quartz (SiO2) is the predominant gangue in the cassiterite, and phase evolution of SnO2–SiO2–Na2CO3 system roasted under CO–CO2 atmosphere was still uncertain. In this study, the effect of SiO2 in cassiterite concentrates on preparation of Na2SnO3 was clarified. The results indicated that Na8SnSi6O18 was inevitably formed when cassiterite and Na2CO3 were roasted above 775 °C under CO–CO2 atmosphere via the reaction of SnO2 + 6SiO2 + 4Na2CO3 = Na8SnSi6O18 + 4CO2, and formation of Na8SnSi6O18 would be increased with increasing roasting temperature and Si/Sn mole fraction. In addition, it was found that Na8SnSi6O18 was insoluble in the leachate at pH value range of 1–14, which, therefore, was enriched in the leach residues. The silicon content of the cassiterite concentrates should be controlled as lower as possible to obtain a higher conversion ratio of Na2SnO3.

Effect of Temperature in Carbothermic Reduction of Indonesian Limonite Ore Using Printed Circuit Boards as Reducing Agent

2020 ◽  
Vol 1009 ◽  
pp. 155-161
Author(s):  
Reza Miftahul Ulum ◽  
Andy Kurnia Wicaksana ◽  
Faizinal Abidin
Keyword(s):  
Carbothermic Reduction ◽  
Printed Circuit Boards ◽  
Printed Circuit Board ◽  
Electronic Waste ◽  
Reduction Process ◽  
Exothermic Peak ◽  
Reducing Agent ◽  
Circuit Board ◽  
Effect Of Temperature ◽  
Printed Circuit

In recent years, there have been increases in the production of electronic waste, such as Printed Circuit Board (PCB), because of the rapid advancement of technology. PCBs are highly valuable, as they contain metals such as copper, silver, and gold. This research aims to investigate the feasibility of using PCB, discarded from laptops as the reducing agent for the carbothermic reduction process of Indonesian limonite ore and the effect of temperature on the carbothermic reduction process, specifically on the phase transformation and the differences in microstructure. Based on the TGA-DSC result, the mixture of limonite and PCB have three endothermic peaks at 90 °C, 290 °C, 450 °C and one exothermic peak at 910 °C, whereas the mixture of limonite and coal has the same trends but the exothermic peak occurs at 1070 °C. To investigate the effect of PCB powder on the reduction of limonite ore, a carbothermic reduction experiment was carried out through the mixing of 8.0 g of limonite ore with 2.0 g of PCB powder (20 wt.%), which was then further compacted. The experiment was carried out at temperature variations of 700 °C, 900 °C, 1100 °C for 1 hour in an inert atmosphere furnace. The products of the reduction process were magnetically separated and then characterized using SEM/EDS and XRD to evaluate the differences in microstructure. This research found that PCB powder is a feasible reducing agent for the reduction of limonite ore.

scholarly journals Volatilization behavior of tin during carbothermic reduction of tin-bearing middling to recover tin

2018 ◽  
Vol 54 (3) ◽  
pp. 419-426
Author(s):  
J. Jing ◽  
Y. Guo ◽  
F. Chen ◽  
F. Zheng ◽  
L. Yang
Keyword(s):  
Carbothermic Reduction ◽  
Reducing Agent ◽  
Reduction Temperature ◽  
Reduction Roasting ◽  
Thermodynamics And Kinetics ◽  
Roasting Process ◽  
Reduction Efficiency ◽  
Reaction Capability ◽  
Coke Powder ◽  
Volatilization Behavior

A new method for selecting reducing agent was proposed in this study. This study dedicated to recovery of tin from tinbearing middling by carbothermic reduction. Volatilization behavior of tin during carbothermic reduction was systematically studied, including the tin volatilization thermodynamics and kinetics, the selecting method of reducing agent, the effects of reducing agent, reduction temperature and effect of time on the tin volatilization rate. The thermodynamic results showed that the SnO2 was reduced to SnO by controlling CO% in the range of 9%~15%, and then volatilized as SnO. The reduction efficiency and the reaction capability with CO2 of three reducing agent were investigated, which indicated tin volatilization was close in nature to the reductant, and it was beneficial to the volatilization by using the coke powder. The experiment results show that the volatilization ratio of tin can reach more than 81.34% when the coke powder is used as the reducing agent at 900?C for 2h. The kinetic of tin volatilization during the reduction roasting process showed that the reaction was controlled by the interface chemical reaction and the activation energy of the reaction was 44.66 kJ/mol.

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