The Preparation of High Purity Silicon Dioxide from Boron Mud - The Solid Wastes of Boromagnesite for Producing Borax by Alkali or Soda

The residual rich SiO2 slag was obtained for magnesium was leached from the boron mud by sulfuric acid. The SiO2 was leached from the residual slag by sodium hydroxide solution. The effect of the leaching temperature and the leaching time, the ratio of the sodium hydroxide solution to slag and the concentration of the sodium hydroxide solution on the leaching efficiency of SiO2 in the residual slag were also studied. The reasonable technical condition as follow : the leaching temperature is 130°C, the leaching time is 6 min, the concentration of the sodium hydroxide solution is 19mol·L-1, the ratio of the sodium hydroxide solution to slag is 2.5:1. The SiO2 leached rate can be stabilized about 85% under this condition. Silicon dioxide was produced by double carbonating the sodium silicate solution and its percentage purity is above 99%.

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Effect of Concentration of Sodium Hydroxide and Degree of Heat Curing on Fly Ash-Based Geopolymer Mortar

Indian Journal of Materials Science ◽

10.1155/2014/938789 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 28

Author(s):

Subhash V. Patankar ◽

Yuwaraj M. Ghugal ◽

Sanjay S. Jamkar

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Sodium Hydroxide ◽

Sodium Hydroxide Solution ◽

Large Change ◽

Sodium Silicate Solution ◽

Silicate Solution ◽

Test Period ◽

Hydroxide Solution ◽

Increase With Increase

Geopolymer concrete/mortar is the new development in the field of building constructions in which cement is totally replaced by pozzolanic material like fly ash and activated by alkaline solution. This paper presented the effect of concentration of sodium hydroxide, temperature, and duration of oven heating on compressive strength of fly ash-based geopolymer mortar. Sodium silicate solution containing Na2O of 16.45%, SiO2 of 34.35%, and H2O of 49.20% and sodium hydroxide solution of 2.91, 5.60, 8.10, 11.01, 13.11, and 15.08. Moles concentrations were used as alkaline activators. Geopolymer mortar mixes were prepared by considering solution-to-fly ash ratio of 0.35, 0.40, and 0.45. The temperature of oven curing was maintained at 40, 60, 90, and 120°C each for a heating period of 24 hours and tested for compressive strength at the age of 3 days as test period after specified degree of heating. Test results show that the workability and compressive strength both increase with increase in concentration of sodium hydroxide solution for all solution-to-fly ash ratios. Degree of heating also plays vital role in accelerating the strength; however there is no large change in compressive strength beyond test period of three days after specified period of oven heating.

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Effects of Alkaline Solution on the Properties of Slag Based Geopolymer

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.877.193 ◽

2018 ◽

Vol 877 ◽

pp. 193-199 ◽

Cited By ~ 1

Author(s):

Suman Saha ◽

C. Rajasekaran

Keyword(s):

Compressive Strength ◽

Sodium Hydroxide ◽

Sodium Silicate ◽

Alkaline Solution ◽

Sodium Hydroxide Solution ◽

Setting Time ◽

Sodium Silicate Solution ◽

Silicate Solution ◽

Hydroxide Solution ◽

Geopolymer Paste

Production of Ordinary Portland Cement (OPC) requires huge quantity of natural resources and energy and it releases large amount of carbon - di - oxide to the environment. Therefore, enormous studies have been carried out throughout the world to establish geopolymer as an alternative binder material for the replacement of OPC to protect the environment. This study intends to explore the effects of alkaline solution on the properties of geopolymer produced with ground granulated blast furnace slag. Properties such as Standard consistency, setting time of slag based geopolymer paste has been determined using Vicat’s apparatus (according to the guidelines given by Indian Standards for OPC). In order to determine the effects of alkaline solution on the properties of geopolymers, the concentration of sodium hydroxide solution has been varied from 6M to 16M and the ratio of sodium silicate solution to sodium hydroxide solution is also varied from 1.0 to 2.0. Results indicate higher standard consistency and significant less setting time for slag based geopolymer paste than that of OPC paste. Compressive strength of the geopolymer paste and mortar cube samples, cured in ambient conditions till the day of testing, is increasing with the increase of the concentration of sodium hydroxide solution. Highest compressive strength is obtained for the samples prepared with alkaline solution having the ratio of sodium silicate solution to sodium hydroxide solution as 1.5. But when the concentration of sodium hydroxide solution is beyond 14M, decreasing trend in compressive strength is observed.

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Fabrication and Characterization of Geopolymers from Japanese Volcanic Ashes

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.92.1 ◽

2014 ◽

Vol 92 ◽

pp. 1-7

Author(s):

Shinobu Hashimoto ◽

Hayami Takeda ◽

Tatsuya Machino ◽

Haruka Kanie ◽

Sawao Honda ◽

...

Keyword(s):

Compressive Strength ◽

Sodium Hydroxide ◽

Sodium Silicate ◽

Volcanic Ash ◽

Sodium Hydroxide Solution ◽

Water Immersion ◽

Sodium Silicate Solution ◽

Silicate Solution ◽

Hydroxide Solution ◽

Volcanic Ashes

Geopolymers were fabricated from some Japanese volcanic ashes. 30 g of volcanic ash with 200μm in diameter was mixed with 10 ml of sodium hydroxide solution with various concentrations to form slurry which became geopolymer after curing. When 8.5~11.5 mol/L of sodium hydroxide solution was used, the compressive strength of the resultant geopolymers reached to 25-35MPa. However, when the volcanic ash with high silica content was used, the compressive strength of the geopolymer was under 20 MPa. Furthermore, the addition of sodium silicate hydrate into starting slurry which was consisted of volcanic ash and sodium silicate solution had not effected on the compressive strength of geopolymer. In contrast, the compressive strength of the geopolymer decreased to 30 % of compressive strength compared to that of original geopolymer after water immersion for 3 days. However, crushing treatment of the volcanic ash contributed to retain the compressive strength. Actually, when 10μm of volcanic ash was used to fabricate geopolymer, the compressive strength improved to 70% compared to that of original geopolymer.

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Effect of Alkaline Activators to Engineering Properties of Geopolymer-Based Materials Synthesized from Red Mud

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.777.508 ◽

2018 ◽

Vol 777 ◽

pp. 508-512 ◽

Cited By ~ 5

Author(s):

Van Quang Le ◽

Minch Quang Do ◽

Minh Duc Hoang ◽

Vo Thi Ha Quyen Pham ◽

Thu Ha Bui ◽

...

Keyword(s):

Sodium Hydroxide ◽

Sodium Silicate ◽

Red Mud ◽

Raw Materials ◽

Sodium Hydroxide Solution ◽

Sodium Silicate Solution ◽

Silicate Solution ◽

High Heat ◽

Engineering Properties ◽

Alumina Production

Geopolymer is an inorganic polymer material formed from alumino-silicate structures. Geopolymer has many outstanding functions in comparison with ordinary materials such as high mechanical strength, high heat and chemical resistance, and lightweight property. The engineering properties of geopolymer-based materials depend on raw materials and synthesized conditions. In which, the aluminosilicate materials having high activity and consisting of many alkaline activators have the possibility of increasing pH in geopolymer paste. In the solution of paste, aluminosilicate compounds are solubilized and then react with alkali-activated ions to form geopolymeric networks. The geopolymer can be synthesized in many different conditions depending on factors of temperature, pressure, and curing conditions. In this study, red mud (RM) was used as the main alumino resource for geopolymerization process. RM is a solid waste residue being left from the mining process of bauxite ores with caustic soda for alumina production. Its disposal remains a global issue in terms of environmental concerns. Formation of RM-based geopolymer was affected by many factors, in which, the alkaline activators are the most important factor. This research was conducted with sodium hydroxide and sodium silicate solutions to elucidate the effect of alkaline activator ratio to the engineering properties of RM-based geopolymers. The results showed that the RM-based geopolymer used sodium silicate solution has more outstanding properties than RM-based geopolymer using sodium hydroxide solution.

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The effect of composition of sodium hydroxide solution on detection accuracy of porous silicon's porosity by gravimetric measurements

Future Energy, Environment and Materials ◽

10.2495/feem130971 ◽

2014 ◽

Author(s):

Chuan Lai ◽

Xueming Li ◽

Zhen Xiang ◽

Xiaogang Guo ◽

Daixiong Zhang ◽

...

Keyword(s):

Sodium Hydroxide ◽

Sodium Hydroxide Solution ◽

Detection Accuracy ◽

Hydroxide Solution ◽

Gravimetric Measurements

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Cotton fibre maturity test (estimation by classification of fibes swollen in sodium hydroxide solution).

10.3403/30308203 ◽

1959 ◽

Keyword(s):

Sodium Hydroxide ◽

Sodium Hydroxide Solution ◽

Cotton Fibre ◽

Hydroxide Solution

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THE NITROGEN DISTRIBUTION OF PROTEINS EXTRACTED BY 0.2 PER CENT SODIUM HYDROXIDE SOLUTION FROM COTTONSEED MEAL, THE SOY BEAN, AND THE COCONUT

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)85896-3 ◽

1922 ◽

Vol 51 (1) ◽

pp. 17-20

Author(s):

W.G. Friedemann

Keyword(s):

Sodium Hydroxide ◽

Cottonseed Meal ◽

Sodium Hydroxide Solution ◽

Nitrogen Distribution ◽

Hydroxide Solution ◽

Cent Sodium

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A Study on a Green Route to Preparation of Silica Powders with Rice Husk Ash

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1010-1012.1015 ◽

2014 ◽

Vol 1010-1012 ◽

pp. 1015-1019

Author(s):

Ze Xin Yang ◽

Lin Dong ◽

Meng Wang ◽

Huan Li

Keyword(s):

Sodium Bicarbonate ◽

Sodium Silicate ◽

Rice Husk ◽

Rice Husk Ash ◽

Sodium Hydroxide Solution ◽

Sodium Silicate Solution ◽

Silicate Solution ◽

Raw Material ◽

Transmission Electron ◽

Thermal Analyzer

The main purpose of this article is to develop an environmentally friendly and economically effective process to produce silica from rice husk ash. Sodium silicate solution was prepared by the reaction of rice husk ash and sodium hydroxide solution, and then the sodium silicate solution was used as the raw material for the preparation of silica with sodium bicarbonate. During the reaction, the by-product can be passed into CO2 to prepare sodium bicarbonate what can be reutilized. Experimental route achieved resource recycling and environment-friendly, low energy consumption, zero emissions and so on. Meanwhile the microstructures of the silica powders were characterized by Transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Thermo gravimetric/Differential thermal analyzer (TG-DTA).The purity of silicon was up to 99.43% and the particle size was 200-300nm.

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The preparation of sodium 4-Amino-3-nitro-benzenesulfonate and some related compounds

Australian Journal of Chemistry ◽

10.1071/ch9821727 ◽

1982 ◽

Vol 35 (8) ◽

pp. 1727 ◽

Cited By ~ 3

Author(s):

J Rosevear ◽

JFK Wilshire

Keyword(s):

Sodium Hydroxide ◽

Nitro Group ◽

Sodium Salt ◽

Sulfonic Acid ◽

Sodium Hydroxide Solution ◽

Hydroxide Solution ◽

Dilute Sodium Hydroxide ◽

Related Compounds

The sodium salt of 4-amino-3-nitrobenzenesulfonic acid (O-nitroaniline-p-sulfonic acid) has been prepared by the action of dilute sodium hydroxide solution on ethyl [(4-chlorosulfonyl-2-nitro)- phenyllcarbamate. Central to this synthesis is the finding that the N-ethoxycarbonyl group, when located ortho to a nitro group (but not to a bromo group), is readily removed by dilute sodium hydroxide solution.

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