Materials Studio simulation for the adsorption properties of CO2 molecules at the surface of sodium silicate and potassium silicate solution under different pressure conditions

Potassium silicate is well known as a fertilizer and source of silica for plants growth. This study aims to infiltrate nitrogen from carbamide (urea) into potassium silicate solution to produced silica potassium nitrogen (Si-K-N) matrix by precipitation method using CO2 as precipitator. Potassium silicate in the range of 3-8% SiO2 was obtained by extracting silica from geothermal sludge using potassium hydroxide solution. Carbamide is added to the potassium silicate solution allowed by mixing and flowing of CO2 gas in reactor glass. The result of IR spectra indicated the presence of N-H groups, potassium and silica in the gel matrix produced from precipitation process while no N-H group appears in the gel matrix produced from precipitation in the absence of carbamide. X-ray fluorescence showed the composition of the product Si-K-N in the range of 40 to 50 %SiO2 and in the range of 50 to 60 %K2O.

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ChemInform Abstract: A Two-Dimensional 29Si NMR Spectroscopic Study of the Structure of the Silicate Anions Present in an Aqueous Potassium Silicate Solution.

ChemInform ◽

10.1002/chin.198836011 ◽

1988 ◽

Vol 19 (36) ◽

Author(s):

C. T. G. KNIGHT

Keyword(s):

Spectroscopic Study ◽

Silicate Solution ◽

Potassium Silicate ◽

29Si Nmr ◽

Two Dimensional ◽

Potassium Silicate Solution

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

Materials ◽

10.3390/ma14112811 ◽

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.

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Silica extraction from bauxite reaction residue and synthesis water glass

Green Processing and Synthesis ◽

10.1515/gps-2021-0028 ◽

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.

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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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