Higher NaOH Concentrations Research Articles

Study on the effectiveness of silica fume-derived activator as a substitute for water glass in fly ash-based geopolymer

To continuously promote the development of geopolymer materials, an alternative water glass (AWG) about silica fume-derived (SF–NaOH) was synthesized. The study of this activator is beneficial to reduce the production cost of geopolymer and the adverse impact on environment. So the properties of fly ash (FA)-based geopolymers activated by AWG were studied, comparing with that activated by NaOH and traditional alkali activators (water glass and NaOH). The results showed that the AWG was a potential and efficient activator because the 90 d compressive strength of FA-based geopolymer activated by AWG could exceed 58 MPa at room temperature. The Initial setting time of FA-based geopolymer could be reduced nearly 5 times with the SF content. The degree of fly ash reaction proved that the alkali concentration played a leading role in the dissolution of the precursor. The activity of the AWG depends on the relative content of Q1 and Q2 units (SiO2 tetrahedron). The SEM analysis illustrated that high NaOH concentration and appropriate amount of available silica could significantly improve the reaction degree of FA, resulting in abundant alkali aluminosilicate gels and dense matrix structure.

Effect of NaOH concentration and aging time on the properties of synthesized Ca(OH)2 by sol–gel method

The sol–gel method is one of the most versatile techniques to produce calcium hydroxide (Ca(OH)2) since it provides a flexible chemical route to synthesize materials with the desired properties. The work aims to investigate the influence of sodium hydroxide (NaOH) concentration and aging time on the properties of the synthesized Ca(OH)2. In the study, Malaysian limestone (CaCO3) from Baling, Kedah was applied as a precursor to synthesized Ca(OH)2 using the sol–gel technique. The synthesis was carried out with varying the NaOH concentration (0.5 M, 1.0 M and 2.0 M) and aging time (12 h, 24 h and 48 h). The synthesized Ca(OH)2 powder was subjected to X-ray Diffraction (XRD), Field Emission Scanning Electron Microscope equipped with Energy Dispersive X-ray Spectroscopy (FESEM-EDX), Fourier Transform Infrared (FTIR) spectroscopy, X-ray Fluorescence (XRF) and Particle Size (PSA) analysis. The results exhibit the existence of calcite and aragonite phases at higher concentrations of NaOH, indicating an incomplete reaction of the hydrolysis process. The particle size of Ca(OH)2 increases as NaOH concentration and aging period increase. At higher concentrations of NaOH, agglomeration of Ca(OH)2 was more likely to occur. These findings suggested the potential use of Malaysian limestone as the precursor for Ca(OH)2 synthesis with desired properties by controlling the sol–gel reactions.

Improved production of titanate nanotubes by hydrothermal method for adsorption of organic dyes

BackgroundIncreasing the yield of nanomaterials using the same reactor size and fixing most of the reactants and conditions will greatly improve the production process by saving time, energy and efforts. Titanate nanotubes are mainly prepared by hydrothermal process, in which TiO2 powder reacts with NaOH at certain conditions to form the desired nanotubes. It was reported that it is a must to use high concentrations of NaOH (10 N) to enable the tubular form formation, and the amount of NaOH from the stoichiometry point of view is much higher than that of TiO2; this means excess amounts of NaOH are not used and washed off. This work was designed to improve the production yield by making use of this excess amount of NaOH.ResultsMore than 60 g of sodium titanate nanotubes was prepared using simple hydrothermal method. The prepared nanotubes were characterized by X-ray powder diffraction, high-resolution transmission electron microscopy, Fourier-transform infrared spectroscopy and BET surface area analysis. The adsorption capacity of these nanotubes was tested against three commonly used dyes: methyl orange, crystal violet and thymol blue. The samples showed great affinity toward crystal violet and lower activity toward methyl orange and thymol blue, where they achieved more than 90% removal efficiency under different experimental conditions.ConclusionsSodium titanate nanotubes were prepared in large amounts using modified hydrothermal method. The obtained nanotubes efficiently removed crystal violet from water. This improved synthesis of titanate nanotubes will reduce the total cost of nanomaterials production, and subsequently the treatment process, since titanate nanotubes are used in adsorption and photocatalysis processes.

Improvement of High-Volume Fly Ash Cementitious Material Using Single Alkali Activation

This research aimed to present the improvement of the cementitious material in high-volume fly ash using only one alkali activator. Fly ash was used as a partial replacement for Portland cement type I, varying from 0 to 60% by weight of the binder. Concentrations of NaOH varying from 0.00 to 1.25 molar were used as alkali activator. Paste properties and mortar compressive strength at the ages of 3, 7, 14, 28, 60, and 90 days of water curing were investigated. The results reveal that fly ash paste with an alkali activator provides shorter initial setting time when compared to control paste without alkali activator. The use of 0.50 molar NaOH concentration in mortar containing fly ash not exceeding 50% by weight of binder provides the highest compressive strength at any age of curing. At that concentration, there is a significant increase in the 28-day compressive strength of up to 45% over that of the control mortar. In addition, higher NaOH concentration (not exceeding 1.00 molar) has a significant positive effect on the compressive strength of mortar with higher fly ash content, especially over longer curing periods.

Experimental investigation on the oxidation of printing ink wastewater under hydrothermal flames

Printing ink wastewater has a strong color and contains high salinity and high concentrations of complex organic compounds, posting a severe threat to the ecological environment and human health. In this work, supercritical water oxidation of printing ink wastewater is performed within a transpiring wall reactor (TWR) to avoid corrosion and salt plugging issues. The high concentration of organic matter in printing ink wastewater is used to form hydrothermal flames for enhanced degradation. Flame temperatures, gaseous and aqueous products characteristics, as well as the anti-corrosion and salt plugging performance of the reactor, are obtained. A remarkable temperature fluctuation due to the multi-component systems indicates the instability of hydrothermal flame. The salt recovery rate of 94.56% and the integrity of the porous tube inner wall indicate that TWR has a good performance in terms of anti-corrosion and salt plugging. Under typical conditions, the removal rates for chemical oxygen demand, total nitrogen, and color are 99.52%, 70.07%, and 97.89%, respectively. Alkanes, nitrogenous compounds, benzodiazepines, and heterocyclic compounds in the aqueous products, and CO, H2, NH3, and CH4 in the gaseous products are the main intermediate products of printing ink wastewater under hydrothermal flames. Ammonia nitrogen, as the main intermediate product, inhibits the complete oxidation of nitrogenous organic compounds. Additionally, higher KNO3 concentrations promote the complete oxidation of nitrogenous organic compounds, while higher NaOH concentrations can increase the pH value and slightly facilitate degradation. In addition, higher feed flow rates prevent deposition and adhesion of additives that occur at high concentrations.

Mechanical and Durability Characteristics Assessment of Geopolymer Composite (GPC) at Varying Silica Fume Content

The present study aimed at assessing mechanical and durability characteristics of ground granulated blast furnace slag (GGBS)-based geopolymer composites at 5%, 10%, 15%, 20%, 25%, and 30% replacement proportion of silica fume at 12 molarity of NaOH. Mechanical properties were assessed using compression and tension tests, whereas durability characteristics were evaluated using ultrasonic pulse velocity test (UPV), acid test, and rapid chloride permeability test (RCPT), and water absorption (WA) test. Additionally, reduction in mass and strength were also determined due to the acid action on the developed composites. A correlation of compressive strength was also established with the splitting tensile strength, UPV, RCPT, and WA. The presence of silica fume and high NaOH concentration in GPC tends to improve the mechanical strength up toa certain level. UPV values obtained were falling in the range of medium to good category. Chloride ion penetration and water absorption values were reduced by around 23% and 26%, respectively, at 10% silica fume replacement. Mass loss and strength loss were reduced as the % of silica fume increased. A good correlation of compressive strength was obtained with tensile strength, UPV, and RCPT with a coefficient of determination of 0.9681, 0.9665, and 0.9208, respectively. Poor correlation was obtained between compressive strength and water absorption.

Effect of NaOH concentration on properties and microstructure of a novel reactive ultra-fine fly ash geopolymer

This study used reactive ultra-fine fly ash (RUFA) as the primary raw materials in the preparation of a novel RUFA geopolymer. Note that the solution to binder weight ratio was maintained at the same level by varying the concentration of the NaOH solution. Extensive analysis was conducted to characterize the flowability and mechanical properties. X-ray diffraction (XRD), Scanning Electron Microscope-Energy Dispersive Spectrometer (SEM-EDS), Fourier transform infrared spectroscopy (FT-IR), mercury intrusion porosimetry (MIP), thermogravimetric (TG), and zeta potential analyses were used to examine the microstructure of RUFA geopolymers. Increasing the concentration of NaOH also led to an increase in compressive strength. A high NaOH concentration of 12 mol/L resulted in compressive strength of 97.6 MPa at 28 days. Finally, increasing the concentration of NaOH increased the formation of the primary reaction geopolymerization product, N-A-S-H gel, resulting in a denser microstructure with lower porosity.

One-pot hydrothermal synthesis and formation mechanism of SrNb2O6–Sr2Nb2O7–Sr5Nb4O15 lamellar perovskites in highly concentrated NaOH solutions

The mechanisms behind the phase formation of SrxNbyO(x+5 y/2) perovskites in hydrothermal reactions are yet not well understood. In this work, we report on the one-pot hydrothermal synthesis of SrNb2O6, Sr2Nb2O7 and Sr5Nb4O15 layered perovskites in highly concentrated NaOH solutions. The mechanisms that govern the crystallization and the crystallite morphology of the synthesized perovskites are explained as a function of the NaOH concentration. The crystal structure, morphology, and optical properties of the obtained SrNb2O6, Sr2Nb2O7 and Sr5Nb4O15 perovskites were analyzed using XRD, EDS, HR-TEM, UV–vis absorption, diffuse reflectance spectroscopy (DRS), and Raman spectroscopy. The element composition and resultant crystalline phases are determined by using EDX and Rietveld refinement techniques, respectively. NaOH concentration is the main parameter for the control over the phase formation. High concentration of NaOH accelerates the hydrolysis rate for the transformation from Nb2O5 to Nb6O198− and finally to NbO67−. These polyanions favor the formation of the different crystalline phases, as high concentration of Nb6O198− the preferential formed phases are SrNb2O6, and Sr2Nb2O7, while high concentration of NbO67− induced the formation of Sr5Nb4O15 as a majority phase. The concentration of NaOH also plays a decisive role in the precipitation of SrNb2O6, Sr2Nb2O7 and Sr5Nb4O15 perovskites, high NaOH concentration promotes the Sr2+ complexation favoring the formation of Sr2+ rich phases.

Reduksi Bahan Organik Kulit Kopi dan Eceng Gondok Terhidrolisis Menggunakan Proses Anaerbik

Coffee pulp and water hyacinth are a biomass source that can be used to feeding material for biogas production as energy an anaerobic digester. But coffee pulp and water hyacinth contain lignin. The Alkaline or base hydrolysis is a method of the solving chemical structure of lignin compounds using a strong acid and base. The focus of research investigated the base hydrolysis with NaOH in coffee pulp and water hyacinth an anaerobic process for organic material reduction. The research design in laboratory conduct of organic materials reduction on coffee pulp and water hyacinth used Completely Random Design (CRD). Anaerobic treatments were without hydrolysis (H1), only the coffee pulp with hydrolysis (H2), only water hyacinth with hydrolysis (H3) and all with hydrolysis (H4). The highest NaOH concentration for lignin reduction on the base hydrolysis was 60 ppm. The analysis of variants with significantly (p<0.05) showed all treated differently. Anerobic treatment of the coffee pulp and water hyacinth (H4) had the highest value organic material reduction. The efficiency of organic material reduction i.e. C/N, BOD and COD was in sequence namely 64.22 ± 0.02; 75.23 ± 0.02 dan 52.55 ± 0.04.

Conversion of Fe-bearing minerals in sludge to nanorod erdite for real electroplating wastewater treatment: Comparative study between ferrihydrite, hematite, magnetite, and troilite

Ferrihydrite, hematite, magnetite and troilite are typical Fe-bearing minerals, and served as major components of Fe-rich sludges generated in water treatment, refining, steel processing and mining industry, respectively. To recycle such Fe-rich sludges to prepare erdite-bearing flocculant, the phase transformation of the four Fe-bearing minerals to nanorod erdite should be clarified. In the study, the four minerals were hydrothermal treated to prepare nanorod erdite separately by simply adding Na2S and NaOH. Among the four minerals, ferrihydrite was weakly crystallized and easily converted to nanorod erdite with diameter of 200–500 nm and length of 2–5 μm, along with dotted distribution of hematite as byproduct. Only a small portion of hematite was involved in the formation of nanorod erdite with length of 2 μm, but the involvement of magnetite and troilite in erdite formation did not occur. The Fe dissolution from Fe-bearing minerals in alkaline solution was a key step for erdite crystallization, which apparently enhanced at high NaOH concentration. By increasing NaOH concentrations from 1 to 6 M, radial growth of nanorod erdite from both ferrihydrite and hematite steadily improved to 5–10 μm and 5 μm, separately. Fer-P, the product of ferrihydrite, contained plenty of nanorod erdite and exhibited remarkable removal efficiency of Cr, Cu and Zn from real electroplating wastewater. By adding 0.5 g Fer-P, the removal percentage of Cr, Cu and Zn were all more than 99.95%, which were higher than other conventional reagents such as polyaluminium chloride, polyferric sulfate, powder activated carbon, and diatomite. The total residual heavy metal concentrations were less than 0.1 mg/L, which met the standard of discharging electroplating-wastewater of China. Nanorod erdite was spontaneously hydrolyzed to generate Fe/S-bearing colloid, which contained abundant Fe–S–H groups for chelating heavy metals in comparison with ligands in electroplating wastewater, maintaining the residual heavy metals at low level. In summary, rather than magnetite/troilite-rich sludge, ferrihydrite/hematite-rich sludge can be served as desirable resources to prepare erdite-bearing flocculant for real electroplating wastewater treatment.

Base activation of persulfate: an effective pretreatment method to enhance glucose production from lignocellulosic biomass

Pretreatment is a necessary process in biorefineries to overcome recalcitrance of biomass and enhance its conversion efficiency for further transformation. NaOH activation of Na2S2O8, which merges alkaline pretreatment and advanced oxidation processes (AOPs) into one process, was performed at room temperature (25 °C) within a short duration (60 min). High concentration of NaOH plays a critically important role in NaOH–Na2S2O8 pretreatment, which not only selectively removed hemicellulose in the lignocellulosic feedstock, but also activated Na2S2O8 to produce strong oxidative radicals, leading to disruption of lignin matrix. The surface area and porosity for the pretreated feedstock were significantly increased compared with those of the pristine counterpart. After pretreatment by 5.12 M NaOH and 0.85 M Na2S2O8, the maximum glucose yield of the feedstock was increased by 47.4% compared with that of pristine counterpart (60.3% vs. 40.9%). This study provides an effective and easily-realizable pretreatment method for the utilization of lignocellulosic biomass.

Physicochemical properties and photocatalytic de-NOx performance of TiO2 nanostructures via microwave hydrothermal strategy

TiO2 nanostructures have been prepared via microwave hydrothermal process using different NaOH concentrations. The physicochemical properties of the products were systematically investigated by using UV–vis Diffuse Reflectance Spectra, X-ray Photoelectron Spectra, Photoluminescence Spectra, Raman, N2 adsorption-desorption, and Transmission Electron Microscope analysis. The results indicated a close correlation between the NaOH concentration and different types of nanostructured titania products obtained from the microwave-assisted hydrothermal process. At low NaOH concentrations (4 M and 6 M), the precursor TiO2 nanoparticles partially converted into a mixture of one dimensional (1D) nanostructures (e.g., nanorods or nanowires) and 2D nanostructures such as nanosheets. As the NaOH concentration is increased to 8 M and 10 M, the obtained TiO2 products contain nanosheet and nanotube-like structures, respectively, with a significantly larger specific surface area. The photocatalytic performance of the synthesized TiO2 products, prepared under different NaOH concentrations, were evaluated through the toxic NOx gas removal efficiencies. The nanostructured TiO2 samples prepared at a higher NaOH concentration have shown improved de-NOx efficiencies than the TiO2–P25 precursor.

EFFECT OF REACTION TIME AND SODIUM HYDROXIDE CONCENTRATION ON DELIGNIFICATION AND ENZYMATIC HYDROLYSISOF BREWER’S SPENT GRAIN FROM WO BRAZILIAN BREWERS

Brazil, being one of the main beer producers, generates brewer’s spent grain as a main by-product of this industry, which is mainly composed of cellulose, hemicelluloses, lignin and extractives. The alkaline pretreatment of brewer’s spent grain received from two breweries is studied in this work, namely breweries Imperial (B1) and Colombina (B2). Factorial design (22) was realized with three experiments at the central point: contact time (30, 60, 90 min) and NaOH concentration (4%, 6%, 8%). It was found that the presence of extractives causes interference in the characterization of the material. The delignification process allowed obtaining materials with lower lignin percentages when higher NaOH concentrations were used, reaching percentages of lignin loss with values between 85-95%, in both materials, but for these conditions, the losses of cellulose were considerable – of 35-43%. Enzymatic hydrolysis of the pretreated materials achieved conversions greater than 70%, emphasizing that the greatest conversions were obtained with material B1, where almost the whole cellulose was hydrolyzed.

TiO2 nanorods integrated with titania nanoparticles: Large specific surface area 1D nanostructures for improved efficiency of dye-sensitized solar cells (DSSCs)

In this work, the impact of alkali concentration on the formation of novel one dimensional TiO2 nanostructures has been studied. The variation of alkali concentration resulted in the change of morphology and structure of P25 nanoparticle precursors under hydrothermal conditions, as confirmed by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) nitrogen adsorption–desorption, X-ray diffraction (XRD) and photoluminescence (PL) spectroscopy. The effects of the annealing temperatures on the surface oxygen vacancies were also studied under various temperatures. In higher NaOH concentrations under annealing, these nanostructures have a peculiar appearance consisting in nanorods with nanoparticles grown on their surface and hence designated herein as “integrated TiO2 nanorods”. The prepared nanostructures were employed as main precursors of photoanode and their performance was fully investigated in dye-sensitized solar cells (DSSCs). TiO2 nanostructures prepared from 12 M alkaline solution at 300 °C had the largest specific surface area (363.15 m2/g) and the best efficiency improvement was about 41% for these TiO2 nanostructures compared to the P25 nanoparticles.

Synthesis, Characterization, and Application of Carboxymethyl Cellulose from Asparagus Stalk End.

Cellulose from Asparagus officinalis stalk end was extracted and synthesized to carboxymethyl cellulose (CMCas) using monochloroacetic acid (MCA) via carboxymethylation reaction with various sodium hydroxide (NaOH) concentrations starting from 20% to 60%. The cellulose and CMCas were characterized by the physical properties, Fourier Transform Infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM) and X-ray diffraction (XRD). In addition, mechanical properties of CMCas films were also investigated. The optimum condition for producing CMCas was found to be 30% of NaOH concentration for the carboxymethylation reaction, which provided the highest percent yield of CMCas at 44.04% with the highest degree of substitution (DS) at 0.98. The melting point of CMCas decreased with increasing NaOH concentrations. Crystallinity of CMCas was significantly deformed (p < 0.05) after synthesis at a high concentration. The L* value of the CMCas was significantly lower at a high NaOH concentration compared to the cellulose. The highest tensile strength (44.59 MPa) was found in CMCas film synthesized with 40% of NaOH concentration and the highest percent elongation at break (24.99%) was obtained in CMCas film treated with 30% of NaOH concentration. The applications of asparagus stalk end are as biomaterials in drug delivery system, tissue engineering, coating, and food packaging.

Behaviors of Adsorption and Elution on Amidoxime Resin for Gallium, Vanadium, and Aluminium Ions in Alkaline Aqueous Solution

ABSTRACT For recovery of gallium from Bayer liquor, adsorption, and elution on amidoxime resin for gallium (Ga), vanadium (V), and aluminum (Al) ions in alkaline solution were systematically investigated by batch and column experiment. Amidoxime resin did not adsorb Al. The adsorption separation efficiency of Ga and V increased with increasing NaOH concentration and decreasing temperature and contact time. The adsorption kinetics of Ga and V are fit by a pseudo-second-order model. The adsorption isotherms of Ga and V could be fit well by the Langmuir model. Gallium was easily eluted using low concentration acid (1~2 mol/L H+), but it was difficult to elute V. Although high concentration acid could elute 70% of V, this treatment would destroy resin. With high NaOH concentration and a long eluting time, more than 50% of V could be eluted at temperatures greater than 50°C, and NaOH did no damage to the resin. The optimum condition of Ga separation from V and Al is at low temperature with short contact time and high NaOH concentration. After adsorption and desorption, a high-purity Ga is obtained, from which V can be recovered V by elution with a strong NaOH concentration at 50°C. FT-IR spectra and XPS showed that the adsorption mechanism of Ga was only related to interaction with oxygen atoms of amidoxime groups (C = NOH). Furthermore, the adsorption mechanism of V was related to both nitrogen and oxygen atoms of amidoxime groups that caused the difficulty of desorbing V from resin.

SOLUBILITY OF PRECURSORS AND CARBONATION OF WATERGLASS-FREE GEOPOLYMERS

Geopolymers have the potential to function as an environmentally friendly substitute for ordinary Portland cement, with up to 80% less CO2 emission during production. The effect is best utilized for geopolymers prepared with amorphous silica instead of waterglass (Na2xSiyO2y+x) to adjust the Si:Al ratio. The reactivity of the precursors with the alkaline activator affects the final mineralogical properties of the binder. The purpose of the present study was to investigate the amount of different phases formed during geopolymerization and to understand the quantitative evolution of carbonation during geopolymer synthesis by determining the solubility of metakaolinite and amorphous SiO2 in NaOH at various concentrations. The solubility was studied by ICP-OES measurements. X-ray diffraction was used for qualitative and quantitative phase analysis of the geopolymers. The solubility of the precursors increased with calcination temperature of metakaolinite, reaction time for amorphous SiO2, and at higher NaOH concentrations. Partial dissolution resulted in free Na+, which is a source for the formation of carbonates in the geopolymers. Thermonatrite occurred prior to trona formation in all samples.

Mechanical strength and permeation properties of high calcium fly ash-based geopolymer containing recycled brick powder

Geopolymer is a ceramic-like material produced by the combination of alumino-silica source material and alkaline activator. High calcium fly ash is an emerging binding material for production of geopolymer while there is currently growing potential to use recycled clay brick as part of the binding material as clay brick is also inherently a ceramic-type material. For geopolymer made with different source materials, it is important to ascertain its compressive strength attainment. Hence, in this study, high calcium fly ash and brick powder from recycled brick were utilized as source materials to prepare geopolymer mortar for evaluation of its flowability, mechanical strength, absorption and sorptivity. The fly ash-based geopolymer mortars were produced with different concentrations of NaOH (6, 8 and 10 M) and Na2SiO3/NaOH ratios (1.5, 2.0 and 2.5). The optimum Na2SiO3/NaOH ratio of 2.5 was then selected to further study the effect of recycled brick powder content (0–20%) on the compressive strength, absorption and sorptivity. This study revealed that among the studied variables, the presence of brick powder is the major factor in reducing the flowability of geopolymer mixtures. The highest 28-day compressive strength of 44.2 MPa was obtained by incorporating 10% brick powder as fly ash substitute along with 10 M NaOH of activator. FESEM-EDS of the specimens indicated that brick powder replacement beyond 10% resulted in formation of inhomogeneous microstructure. Higher concentration of NaOH, though, increased the water absorption and sorptivity of the high calcium fly ash-based geopolymer mortars.

Effect of Alkalization on the Bacterial Cellulose Film Structure Produced Using the Pineapple Waste

Bacterial cellulose is natural polymers materials produced by Acetobacter xylinum with attractive physical properties because they are ordinary and uniform in structure. An alternative of cellulose from renewable source with more effective results to produce bacterial cellulose fibers. For this reason, the purpose of this paper is to show the effect of alkalization process on the bacterial cellulose film structure. The methods were the synthesis of bacterial cellulose using the extracts of pineapple waste. The pellicle product was treated using in the concentration of 0%, 1%, 5% and 10% then bacterial fiber films obtained from drying process of treated pellicle. Furthermore, the XRD and FTIR of bacterial cellulose were observed. The results of the structure of bacterial cellulose film was changed after a process in a high concentration of NaOH.

Effect of Chemical Solution on Tensile Strength of Bamboo Fiber

This study aims to investigate the effect of a chemical solution on the tensile strength of the bamboo fiber. The bamboo woods were cut into the size of small pieces 60 mm x 5 mm x 1 mm. Seven solutions were used in this work which is distilled water (control conditions), ASH and NaOH solution with concentrations of 20%, 10%, and 5% by weight. The bamboo pieces were soaked in the solution with 11 different soaking times except soaking in distilled water for 5 different soaking times. After that processed bamboo pieces were washed and dried at room temperature for 1 week. They were separated by hand to get processed bamboo fiber with cross-section size between 0.06-0.27 mm2. For all specimen, more than 5 pieces of processed bamboo fibre were tested following to ASTM D3039. The results show that the cross-section area in rang 0.06-0.27 mm2 from raw materials have similar tensile strength with 290 MPa [1]. The higher concentration of NaOH, the lower value of the tensile strength which decreases and reach below 100 MPa for 20% NaOH solution. For ASH solution, the values of the tensile strength as the function of soaking time are the same inclination with the different concentration. The tensile strength of processed bamboo fibres is pretty splattered between 200-400 MPa for the soaking time less than 48 hours. While tensile strengths have the range between 275-300 MPa for the soaking time more than 48 hours. Because some fungus grew on bamboo fibre surface soaked in distilled water, the tensile strength of processed bamboo fibres soaked in 20% ash solution is greater 100 MPa than the tensile strength of bamboo fiber soaked in distilled water for the soaking time more than 120 hours.