Effect of sodium hydroxide concentration on the performance of alkali-activated recycled cement-based materials

2021 ◽  
Author(s):  
ZunBang Xi ◽  
ZuoQi Sun ◽  
JianMing Wu ◽  
YuChen Fu ◽  
YaJun Wang ◽  
...  
Keyword(s):  
Sodium Hydroxide ◽  
Sodium Hydroxide Concentration ◽  
Cement Based Materials ◽  
Alkali Activated

Effect of sodium hydroxide concentration on strength and microstructure of alkali-activated natural pozzolan and limestone powder mortar

2020 ◽  
pp. 121530
Author(s):  
Adeshina Adewale Adewumi ◽  
Mohd Azreen Mohd Ariffin ◽  
Moruf Olalekan Yusuf ◽  
Mohammed Maslehuddin ◽  
Mohammad Ismail
Keyword(s):  
Sodium Hydroxide ◽  
Limestone Powder ◽  
Natural Pozzolan ◽  
Sodium Hydroxide Concentration ◽  
Alkali Activated

Study on the Chemical Modification Process of Jute Fiber

TAPPI Journal ◽  
2010 ◽  
Vol 9 (2) ◽  
pp. 23-29 ◽  
Author(s):  
Wei-ming Wang ◽  
Zai-sheng Cai ◽  
Jian-yong Yu
Keyword(s):  
Sodium Hydroxide ◽  
Sodium Silicate ◽  
Treatment Time ◽  
Jute Fiber ◽  
Process Conditions ◽  
Silicate Concentration ◽  
Sodium Hydroxide Concentration ◽  
Liquor Ratio ◽  
Degumming Process ◽  
Selection Of

Degumming of pre-chlorite treated jute fiber was studied in this paper. The effects of sodium hydroxide concentration, treatment time, temperature, sodium silicate concentration, fiber-to-liquor ratio, penetrating agent TF-107B concentration, and degumming agent TF-125A concentration were the process conditions examined. With respect to gum decomposition, fineness and mechanical properties, sodium hydroxide concentration, sodium silicate concentration, and treatment time were found to be the most important parameters. An orthogonal L9(34) experiment designed to optimize the conditions for degumming resulted in the selection of the following procedure: sodium hydroxide of 12g/L, sodium silicate of 3g/L, TF-107B of 2g/L, TF-125A of 2g/L, treatment time of 105 min, temperature of 100°C and fiber to liquor ratio of 1:20. The effect of the above degumming process on the removal of impurities was also examined and the results showed that degumming was an effective method for removing impurities, especially hemicellulose.

scholarly journals Monitoring the course of early-age reactions in alkali activated aluminosilicates

2019 ◽  
Vol 282 ◽  
pp. 02056
Author(s):  
Miloš Jerman ◽  
Vratislav Tydlitát ◽  
Robert Černý
Keyword(s):  
Heat Flow ◽  
Sodium Hydroxide ◽  
Water Glass ◽  
Early Time ◽  
Early Age ◽  
Heat Power ◽  
Reaction Heat ◽  
Flow Calorimeter ◽  
Isothermal Heat Flow Calorimeter ◽  
Alkali Activated

In this paper the reaction heat development of alkali activated aluminosilicates is studied by an isothermal heat flow calorimeter. The highest reaction activity is observed during two hours after mixing. The hydration heat power at early time is influenced mainly by the composition of tested mixtures involving ceramic dust as precursor and different amounts of sodium hydroxide and water glass as activators and by temperature.

scholarly journals Central Composite Design and Desirability of RSM for Optimization of Biodiesel Production from Mixture of Animal Waste Fat Oil and used Cooking Oil

2020 ◽  
Vol 9 (4) ◽  
pp. 1565-1571
Keyword(s):  
Reaction Time ◽  
Sodium Hydroxide ◽  
Maximum Yield ◽  
Animal Waste ◽  
Sodium Hydroxide Concentration ◽  
Used Cooking Oil ◽  
Input Parameters ◽  
Desirability Approach ◽  
Central Composite ◽  
Waste Fat

In this work, central composite design(CCD) and desirability approach of Response surface methodology (RSM) has been used for optimization of biodiesel yield produced from mixture of animal waste fat oil and used cooking oil (AWO) in the ratio of 1:1through alkaline transesterification process. In this work, methanol quantity, reaction time and sodium hydroxide concentration are selected as input parameters and yield selected as response. The combined effect of methanol quantity, reaction time and sodium hydroxide concentration were investigated and optimized by using RSM. The second order model is generated to predict yield as a function of methanol quantity, reaction time and sodium hydroxide concentration. A statistical model predicted the maximum yield of 96.9779% at 35ml methanol quantity (% v/v of oil), 75 min. reaction time and 0.6g (% wt./v of oil) of sodium hydroxide. Experimentally, the maximum yield of 97% was obtained at the above optimized input parameters. The variation of 0.02% was observed between experimental and predicted values. In this work, an attempt has also made to use desirability approach of RSM to optimize the input parameters to predict maximum yield. Desirability approach predicts maximum yield (97.075%) at CH3OH (35.832% vol. /vol. of oil), NaOH (0.604 % wt./vol. of oil) and reaction time (79.054min.) was found for the AWO.

Study of Manufacture Process and Properties of Tailings and Slag Based Geopolymers

2010 ◽  
Vol 156-157 ◽  
pp. 803-807
Author(s):  
Fu Sheng Niu ◽  
Shan Shan Zhou ◽  
Shu Xian Liu ◽  
Jin Xia Zhang
Keyword(s):  
Compressive Strength ◽  
Sodium Hydroxide ◽  
Sodium Silicate ◽  
Raw Material ◽  
Silicate Concentration ◽  
High Compressive Strength ◽  
Curing Period ◽  
Manufacture Process ◽  
Alkali Activated

The tailings and slag based geopolymers was prepared by sodium silicate, sodium hydroxide alkali-activated tailings and slag. The compressive strength in 7 d under different raw material proportion were tested. The result indicated that tailings and slag based geopolymers has high compressive strength . As the tailings in slag is 80%, the compressive strength in 7d can reach 45.10 MPa . As the Na2SiO3 to NaOH ratio is 0.5, the compressive strength in 7d can reach 63.79 MPa. As the NaOH and sodium silicate concentration in the solution is 35%, the compressive strength in 7d can reach 38.35 MPa respectively; As the curing period is 14 d , the compressive strength can reach 71.25 MPa. As the steel scoria in solid is 20%, the compressive strength in 7d can reach 61.86 MPa respectively.

scholarly journals Pressure-Induced Geopolymerization in Alkali-Activated Fly Ash

2018 ◽  
Vol 10 (10) ◽  
pp. 3538 ◽  
Author(s):  
Sol Park ◽  
Hammad Khalid ◽  
Joon Seo ◽  
Hyun Yoon ◽  
Hyeong Son ◽  
...  
Keyword(s):  
Fly Ash ◽  
Sodium Hydroxide ◽  
Sodium Silicate ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Elevated Pressure ◽  
X Ray Diffraction ◽  
27Al Mas Nmr ◽  
Alkali Activated

The present study investigated geopolymerization in alkali-activated fly ash under elevated pressure conditions. The fly ash was activated using either sodium hydroxide or a combination of sodium silicate solution and sodium hydroxide, and was cured at 120 °C at a pressure of 0.22 MPa for the first 24 h. The pressure-induced evolution of the binder gel in the alkali-activated fly ash was investigated by employing synchrotron X-ray diffraction and solid-state 29Si and 27Al MAS NMR spectroscopy. The results showed that the reactivity of the raw fly ash and the growth of the zeolite crystals were significantly enhanced in the samples activated with sodium hydroxide. In contrast, the effects of the elevated pressure conditions were found to be less apparent in the samples activated with the sodium silicate solution. These results may have important implications for the binder design of geopolymers, since the crystallization of geopolymers relates highly to its long-term properties and functionality.

scholarly journals Alkali Activated Paste and Concrete Based on of Biomass Bottom Ash with Phosphogypsum

2020 ◽  
Vol 10 (15) ◽  
pp. 5190
Author(s):  
Danutė Vaičiukynienė ◽  
Dalia Nizevičienė ◽  
Aras Kantautas ◽  
Vytautas Bocullo ◽  
Andrius Kielė
Keyword(s):  
Compressive Strength ◽  
Sodium Hydroxide ◽  
Sodium Hydroxide Solution ◽  
Bottom Ash ◽  
Control Sample ◽  
Test Methods ◽  
X Ray ◽  
Hydroxide Solution ◽  
Fine Grained ◽  
Alkali Activated

There is a growing interest in the development of new cementitious binders for building construction activities. In this study, biomass bottom ash (BBA) was used as aluminosilicate precursor and phosphogypsum (PG) was used as a calcium source. The mixtures of BBA and PG were activated with the sodium hydroxide solution or the mixture of sodium hydroxide solution and sodium silicate hydrate solution. Alkali activated binders were investigated using X-ray powder diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy (SEM) test methods. The compressive strength of hardened paste and fine-grained concrete was also evaluated. After 28 days, the highest compressive strength reached 30.0 MPa—when the BBA was substituted with 15% PG and activated with NaOH solution—which is 14 MPa more than control sample. In addition, BBA fine-grained concrete samples based on BBA with 15% PG substitute activated with NaOH/Na2SiO3 solution showed higher compressive strength compered to when NaOH activator was used −15.4 MPa and 12.9 MPa respectfully. The NaOH/Na2SiO3 activator solution resulted reduced open porosity, so potentially the fine-grained concrete resistance to freeze and thaw increased.

Comparison of Selected Properties of Portland Cement Based Materials and Alkali Activated Materials Based on Granulated Blast Furnace Slag

2016 ◽  
Vol 865 ◽  
pp. 107-113 ◽  
Author(s):  
Pavel Mec ◽  
Jana Boháčová ◽  
Josef Koňařík
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Water Glass ◽  
Sodium Metasilicate ◽  
Alkali Activation ◽  
Granulated Blast Furnace Slag ◽  
Cement Based Materials ◽  
One Year ◽  
Furnace Slag ◽  
Alkali Activated

Alkali activated systems are materials formed by alkali-activation of latent hydraulic or pozzolanic materials. The outcome is a polymeric structure with properties comparable to materials based on cement.The principle of the experiment is to compare selected properties of alkali-activated materials based on blast furnace slag and using various types of activator (sodium water glass, potassium water glass, DESIL AL and sodium metasilicate) to binders based on white and Portland cements of the highest quality. The samples were left for one year in environments simulating the conditions in the interior and exterior. Selected physical-mechanical properties were evaluated and compared.

Stress Corrosion Cracking of Steam Generator Tube Materials in Sodium Hydroxide Solutions

CORROSION ◽  
1978 ◽  
Vol 34 (11) ◽  
pp. 369-378 ◽  
Author(s):  
R. S. PATHANIA ◽  
J. A. CHITTY
Keyword(s):  
Stress Corrosion ◽  
Sodium Hydroxide ◽  
Applied Stress ◽  
Steam Generator ◽  
Stress Corrosion Cracking ◽  
Corrosion Cracking ◽  
Sodium Hydroxide Concentration ◽  
Inconel 600 ◽  
Steam Generator Tubing ◽  
Monel 400

Abstract Stress corrosion cracking (SCC) tests were carried out on specimens of Monel 400, Inconel 600, and Sanicro 30 steam generator tubing in solutions containing 10 to 500 g NaOH/kg H2O at 300 C for times up to 600 days. Applied stress and sodium hydroxide concentration had a significant effect on the (SCC) resistance of the three materials.

Sign in / Sign up

Export Citation Format

Share Document