scholarly journals Silica extraction from bauxite reaction residue and synthesis water glass

2021 ◽  
Vol 10 (1) ◽  
pp. 268-283
Author(s):  
Yunlong Zhao ◽  
Yajie Zheng ◽  
Hanbing He ◽  
Zhaoming Sun ◽  
An Li
Keyword(s):  
Sodium Silicate ◽  
Water Glass ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Hydrated Calcium Silicate ◽  
Precipitated Silica ◽  
Alumina Gel ◽  
Silica Alumina ◽  
Element Removal ◽  
Hydrated Calcium

Abstract Bauxite reaction residue (BRR) produced from the poly-aluminum chloride (PAC) coagulant industry is a solid acidic waste that is harmful to environment. A low temperature synthesis route to convert the waste into water glass was reported. Silica dissolution process was systematically studied, including the thermodynamic analysis and the influence of calcium and aluminum on the leaching of amorphous silica. Simulation studies have shown that calcium and aluminum combine with silicon to form hydrated calcium silicate, silica–alumina gel, and zeolite, respectively, thereby hindering the leaching of silica. Maximizing the removal of calcium, aluminum, and chlorine can effectively improve the leaching of silicon in the subsequent process, and corresponding element removal rates are 42.81%, 44.15%, and 96.94%, respectively. The removed material is not randomly discarded and is reused to prepare PAC. The silica extraction rate reached 81.45% under optimal conditions (NaOH; 3 mol L−1, L S−1; 5/1, 75°C, 2 h), and sodium silicate modulus (nSiO2:nNa2O) is 1.11. The results indicated that a large amount of silica was existed in amorphous form. Precipitated silica was obtained by acidifying sodium silicate solution at optimal pH 7.0. Moreover, sodium silicate (1.11) further synthesizes sodium silicate (modulus 3.27) by adding precipitated silica at 75°C.

Effect of the gelation on the properties of precipitated silica powder produced by acidizing sodium silicate solution at the pilot scale

2012 ◽  
Vol 209 ◽  
pp. 531-536 ◽  
Author(s):  
Dang Viet Quang ◽  
Jong-Kil Kim ◽  
Jin-Koo Park ◽  
Seok-Hoon Park ◽  
Gideon Elineema ◽  
...  
Keyword(s):  
Sodium Silicate ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Pilot Scale ◽  
Silica Powder ◽  
Precipitated Silica

Precipitated Silica from Sodium Silicate by CO2 on Fixed Bed Column

2019 ◽  
Vol 966 ◽  
pp. 14-18
Author(s):  
Retno Dewati ◽  
Suprihatin ◽  
Ketut Sumada ◽  
Srie Muljani
Keyword(s):  
Sodium Silicate ◽  
Fixed Bed ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Ph Control ◽  
Fixed Bed Column ◽  
Precipitated Silica ◽  
Silica Concentration ◽  
Control Apparatus

The precipitated silica prepared by reaction of sodium silicate and gas CO2 on fixed bed column have been production successfully. In this study, silica from bagasse was extraction by sodium hydroxide 2N solution to produce sodium silicate solution. The sodium silicate solution was dilute by demineralize water to produce some concentration in the range of 0.33-0.98 %SiO2. Fixed bed column has a diameter of 7.5 cm with a height of 50 cm and a pH control apparatus. CO2 gas and sodium silicate liquid are both flowed from under of the column with a specified flow rate. The precipitate process was carried out on a fixed bed column with high of bed in the range of 10-30 cm. The effect of silica concentration and the high of the bed on the characterize of the precipitated silica product have been studied. The precipitated silica product characterized by XRF, XRD, SEM-EDX and BET. The quality of precipitated silica produced in the range concentration of 95-98 w% SiO2, surface area (BET) in the range of 46.1 – 58.8 m2/g.

Assessing the Effect of Protective Coatings on the Resistance of the Concrete Floor to the Abrasion

2019 ◽  
Vol 808 ◽  
pp. 123-128
Author(s):  
Karel Mikulica ◽  
Rudolf Hela
Keyword(s):  
Service Life ◽  
Sodium Silicate ◽  
Abrasion Resistance ◽  
Water Glass ◽  
Protective Coatings ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Test Method ◽  
Concrete Floor ◽  
Positive Effect

How to extend your lifetime before you start using it or more often during use is a matter for every investor. In this paper, we will try to assess whether the use of protective coatings on concrete floors has a positive effect on the service life. The referee in our case will be the highly abrasive test method Böhme, which determines abrasion resistance. For comparison, we chose coatings based on sodium silicate solution, ie water glass. The market for these protective coatings is very diverse, so we have chosen to select products of renowned and unknown producers in different price ranges to cover the widest possible market.

scholarly journals Synthesis and Characteristic of Precipitated Nano-Silica

2013 ◽  
Vol 6 (1) ◽  
pp. 917-922 ◽  
Author(s):  
Mohammad Sadeghi ◽  
Mahboubeh Dorodian ◽  
Masoumeh Rezaei
Keyword(s):  
Particle Size ◽  
Electron Microscope ◽  
Sulfuric Acid ◽  
Sodium Silicate ◽  
Sodium Dodecyl ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Precipitation Process ◽  
Nano Silica ◽  
Precipitated Silica

The reaction of precipitation of amorphous silicon dioxide from aqueous solution of sodium silicate and sulfuric acid has been studied. The factors affecting the precipitation process of the sodium silicate solution such as sodium silicate concentration and addition of anionic surfactant (sodium dodecyl sulfate, SDS) on particle size, size distribution and degree of agglomeration of the precipitated silica were examined. The precipitation of silica from the produced sodium silicate solution was carried out using sulfuric acid at pH 7. Scaning electron microscope (SEM), transmission electron microscope (TEM) and Dynamic light scattering (DLS) have been used for characterization of the produced nano-silica. The surface area of silica was tested by oil absorption method according to ASTM standard. Results showed that the particle size of the precipitated silica gel was decreased with increasing Na2SiO3 and SDS concentrations and Particle size of about 44nm can be achieved at 20% Na2SiO3 and 200ppm SDS. But with decreasing particle size, degree of agglomeration also increased.

scholarly journals Printability and Setting Time of CSA Cement with Na2SiO3 and Gypsum for Binder Jetting 3D Printing

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2811
Author(s):  
Okpin Na ◽  
Kangmin Kim ◽  
Hyunjoo Lee ◽  
Hyunseung Lee
Keyword(s):  
3D Printing ◽  
Sodium Silicate ◽  
Setting Time ◽  
Sodium Silicate Solution ◽  
Preliminary Test ◽  
Silicate Solution ◽  
Calcium Sulfoaluminate Cement ◽  
Calcium Sulfoaluminate ◽  
Parametric Studies ◽  
Binder Jetting

The purpose of this study is to optimize the composition of CSA (calcium sulfoaluminate) cement with sodium silicate (Na2SiO3) and gypsum for binder jetting 3D printing. The preliminary test was carried out with an applicator to decide the proper thickness of one layer before using the 3D printer. A liquid binder was then selected to maintain the shape of the particles. Based on the results, the optimal mixture of dry materials and a liquid activator was derived through various parametric studies. For dry materials, the optimum composition of CSA cement, gypsum, and sand was suggested, and the liquid activator made with sodium silicate solution and VMA (viscosity modified agent) were selected. The setting time with gypsum and sodium silicate was controlled within 30 s. In case of the delayed setting time and the rapid setting mixture, the jetting line was printed thicker or thinner and the accuracy of the printout was degraded. In order to adjust the viscosity of the liquid activator, 10% of the VMA was used in 35% of sodium silicate solution and the viscosity of 200–400 cP was suitable to be sprayed from the nozzle. With this optimal mixture, a prototype of atypical decorative wall was printed, and the compressive strength was measured at about 7 MPa.

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

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.

Consolidation mechanism of materials obtained from sodium silicate solution and silica-based aggregates

2011 ◽  
Vol 357 (15) ◽  
pp. 3013-3021 ◽  
Author(s):  
Séka Simplice Kouassi ◽  
Monique Tohoué Tognonvi ◽  
Julien Soro ◽  
Sylvie Rossignol
Keyword(s):  
Sodium Silicate ◽  
Sodium Silicate Solution ◽  
Silicate Solution
Sign in / Sign up

Export Citation Format

Share Document