Effect Of Alkali Concentration Research Articles

3D printable earth-based alkali activated “ink”: Effect of alkali concentration and binder-to-aggregate ratio

This research attempts to investigate the effect of activator concentration (4 mol/L (M) and 8M) and binder-to-aggregate (B:A) ratio (ranging from 1:1 to 1:3 by weight) on extrudability and buildability of 3D printable natural earth-based alkali-activated materials (EAAM). It is found that natural clay in soil, used to replace 25 % of M-sand, imparts higher thixotropy, evident from 90 to 100 % recovery in viscosity compared to 65–80 % for corresponding control (containing only M-sand and no soil). Presence of clay increases the dynamic yield stress than control but reduces the plastic viscosity by 80 – 90 % in EAAM compared to corresponding control where interlocking between sand particles resists smooth extrusion of the material. EAAMs made with 8M NaOH have higher flow retention and maintain 95–100 % recovery in viscosity for longer duration than 4M EAAM. This contributes to superior extrusion quality of 8M EAAM than 4M EAAM. The findings suggest that binder content can be reduced as concentration of NaOH is increased from 4M to 8M. This is evident from lower layer deformation (0.09 % of original height) under self-weight and higher 3D printed buildable height of at least 457 mm in 8M EAAM with B:A of 1:2 compared to a maximum of 375 mm for 4M EAAM at higher B:A of 1:1. Ratios of wet compressive strength to dry compressive strength vary between 0.92 and 1.09 in 8M EAAM compared to 0.79 – 0.85 for 4M EAAM at 28-day age, suggesting lower sensitivity to moisture due to improved clay stabilization. Based on the strength and moisture sensitivity, the developed material can serve as a low-carbon and durable alternative to Portland cement in the construction of masonry elements in buildings, including cavity walls, panels, flooring tiles and façade members.

Synthesis of Linoleic Acid of Conjugated Isomers from Sesame (Sesamum Indicum) Seed Oil: Its Use and Effect in a Microstructured Product Type Oil-in-Water Emulsion

The development of functional foods is an area of great interest and innovation in the food industry. The use of conjugated linoleic acid (CLA) in food formulations has been growing in recent years due to its multiple health benefits. In this study, conjugated linoleic acid was obtained from sesame oil, and its use in the formulation of oil-in-water food emulsions was evaluated. Conjugated linoleic acid (CLA) was synthesized from the linoleic acid present in sesame oil using the alkaline isomerization method using proplyeneglycol as a solvent. The effect of alkali concentration (NaOH) and reaction time on the conversion of linoleic acid to CLA was evaluated. A 96.6% conversion of CLA was obtained with a NaOH concentration of 7% and a reaction time of 2 h. Emulsions were prepared using CLA as oil phase and soy lecithin, tween 80, carboxymethylcellulose as emulsifying agents. Emulsions with mixtures of carboxymethylcellulose and tween 80 were stable, presenting a non-Newtonian fluid behavior of pseudoplastic type (n<1). The Ostwald-de-Waele model shows an optimal fit to the experimental data of apparent viscosity (R2>0.99 ), and its microstructural characterization shows a homogeneous particle distribution. These results show that the alkaline isomerization process using propylene glycol as a solvent is an excellent alternative for the synthesis of CLA from vegetable oils such as sesame oil and its application in the development of microstructured products such as functional emulsions, and their subsequent application in the development of new food products with beneficial health characteristics.

Study on mechanical properties and damage mechanism of alkali-activated slag concrete

The cement industry has become one of the important sources of greenhouse gas emissions, and the alkali-activated slag (AAS) has the same mechanical properties and lower carbon emissions as cement in the production process. Therefore, it can be used as an alternative binder for low-carbon buildings. The effect of alkali concentration (mass ratio of Na2O to binder) on the macro-mechanical properties and meso-damage mechanism of alkali-activated slag concrete (AASC) under uniaxial compression was investigated in this work. Six kinds of concrete with alkali concentration of 2 %, 4 %, 6 %, 8 %, 10 % and 12 % were prepared. The microscopic characteristics of AASC were characterized by nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), x-ray diffraction (XRD) and x-ray energy dispersive spectroscopy (EDS); the meso-damage evolution mechanism of AASC was discussed by statistical damage theory. The results showed that the peak stress and elastic modulus of AASC specimens increased, and the microstructure became denser with the increase of alkali concentration. However, the mechanical properties of the specimen deteriorated to some extent when the alkali concentration exceeded 6 %; for example, the peak stress decreased by 24.00 MPa when the alkali concentration was increased from 6 % to 12 % at the age of 28d. Based on the statistical damage theory, the effective stress concept was introduced to quantitatively analyze the mesoscopic damage evolution of AASC. Both fracture and yielding damage modes were considered. By exploring the regular changes of the mesoscopic parameters, the connection between the macroscopic mechanical properties and the mesoscopic damage mechanism was established. Based on the above mechanical properties and mesoscopic damage results, the alkali concentration of 6 % can be used as the best mixture proportions of AASC.

Investigation of superparamagnetic iron oxide nanoparticles in air environment for elevated saturation magnetization

Iron oxide nanoparticles have garnered interest for their unique properties and wide application areas. For applications, superparamagnetic nanoparticles are required so that they can be magnetized by an external magnetic field and rapidly demagnetize again when the field is removed. High saturation magnetization, Ms is also required for applications to provide easy magnetic control over separation and targeting. For magnetically controlled applications, superparamagnetic iron oxide nanoparticles with a high Ms are important. In this study, superparamagnetic iron oxide nanoparticles were co-precipitated under air atmosphere and the effects of alkali concentration, stirring rate and reaction time on the structural and related magnetic properties were investigated to obtain the high Ms for each parameter. According to the structural results, it is challenging to obtain magnetite nanoparticles under air atmosphere due to oxidizing effect. The increase of Ms values with the increase of alkali concentration may come from the phase of the samples although the crystal size of the nanoparticles is getting smaller. It can be said that there is an optimum stirring rate to obtain the highest Ms under air atmosphere rather than an uptrend/downtrend. The maximum Ms of 69.2 emu g−1 was obtained for superparamagnetic iron oxide nanoparticles synthesized at 700 rpm. With the increase of reaction time, magnetic size of the nanoparticles is observed to decrease in contrast with the increase of physical particle size. The maximum Ms value for the reaction time parameter is 67.3 emu g−1 at 15 min. Due to their high Ms values and superparamagnetic nature, the nanoparticles synthesized under study may find use in magnetic separation, water purification, and other related fields.

Influence of alkali treatment on thermal stability of polyester composites reinforced with Bambusa maculat fibers

The various species of bamboo plants cultivated in Indonesian people's plantations are apus bamboo (Gigantochloa apus) (GA), wulung bamboo (Gigantochloa atroviolacea) (GV), and tutul bamboo (Bambusa maculat) (BM). Apart from being used as a craft material and household utensils, bamboo can be made into natural fiber as a reinforcement for polyester composites. In this research, Bambusa maculat fiber was used. In this work, BM fibers were treated with Alkali with NaOH solutions with concentrations of 2, 5, and 8% by weight respectively at room temperature. The next procedure is that the BM fibers are used as composite reinforcing fibers, arranged unidirectional the polyester composites. The manufacturing technique is using hot pressing molding technique. The effect of alkali concentration on the thermal performance of polyester composites was examined using differential scanning calorimetry (DSC) and thermogravimetric (TG) analysis. As the result, the alkaline treatment of BM bamboo fiber with a NaOH concentration of 5%, causes the BM bamboo fiber as reinforcement and matrix to have a tight interface and strong interfacial bonding, allowing the composite to have the best thermal stability among other composites.

Orthogonal test of alkali-activated slag solidified construction spoil, fluidity, compressive strength, water resistance and carbon emission

To dispose of the construction spoil (CS) sustainably, using alkali-activated slag (AAS) to solidify CS and prepare solidified construction spoil (SCS) as building materials has great potential. The effects of alkali concentration (Na2O%), modulus, binder-soil ratio (B/S), liquid-solid ratio, and sand content on the fluidity, compressive strength, water resistance, and carbon emission factor of SCS were studied via orthogonal experimental methods. It was found that the increasing fluidity was mainly affected by the increasing sand content and liquid-solid ratio, and the increasing compressive strength, water resistance, and carbon emission factor were mainly affected by the increasing Na2O% and B/S. Compared with cement, using AAS can reach higher fluidity, compressive strength, and water resistance, and lower carbon emissions of SCS. Finally, considering the influence of sand content on the properties of SCS, the sand washing decisions during the disposal process were reevaluated via life cycle assessment (LCA). Compared to transportation and landfill, preparing SCS with or without washing sand can significantly reduce equivalent carbon emissions, and the latter can result in lower equivalent carbon emissions and better working and physical performance of SCS than the former. From practical engineering considerations, it was suggested that the CS with low sand content doesn't need to wash sand.

The mechanism of alkali-induced rice protein gel formation: Effect of alkali concentration and temperature

Rice protein (RP) is a high-quality hypoallergenic plant protein, but its extremely poor water solubility makes it difficult to be applied in liquid food systems. Therefore, in-depth exploration of its gel properties is an effective way to broaden the application scenarios of RP. In this work, it was first found that the rate and strength of gel formation by RP at 25 °C strongly depended on the increase in alkali concentration (from 0.05 M to 0.125 M), i.e., alkali concentrations above 0.075 M were sufficient to induce the formation of a stable gel by 10% (w/v) of RP in 0.5 h. Increasing the temperature during alkali-induced RP gel formation (50 °C, 80 °C) greatly increased the rate of gel formation, whereas prolonged (>30 min) heat treatment resulted in liquefaction of the gel. A more in-depth analysis revealed that the alkali was able to depolymerize glutelin within the agglomerates in its native state, thereby forming a gel network among glutelin molecules at lower alkali concentrations (CNaOH = 0.075 M) mainly through hydrophobic interactions. Whereas, higher alkali concentration (CNaOH = 0.125 M) resulted in the rapid transformation of exposed free sulfhydryl groups into disulfide bonds, thus exerting a major contribution to the gel network, followed by hydrogen bonding. Furthermore, the phenomenon of heat-induced gel liquefaction was mainly attributed to the dissociation of glutelin subunits and was accompanied by an increase in the disordered structure of proteins in the amide III region. These findings may provide a scientific basis for the development of rice protein gel foods.

Resource Utilization of Bovine Hair Recycling from Enzymatic Unhairing during Leather Manufacturing

With the development of enzymatic unhairing technology in the leather industry, enhancing the recycling of bovine hair is a new issue emerging in leather-making. In this work, the effects of alkali concentration, time, and temperature in the pretreatment, as well as enzyme dosage, time, temperature, and pH in the following treatment on the dissolution performance and keratin yield of bovine hair were investigated. Hence, the extraction process of keratin from bovine hair by the alkali-enzyme method was optimized. The results sho that the optimal conditions for the keratin extraction are as follows: for the pretreatment with alkali, the alkali concentration is 0.4 M, the pretreatment time is 1.0 h, the pretreatment temperature is 65°C, and for the following enzymatic treatment, the enzyme dosage is 3324 U/g bovine hair, the action time is 4.0 h, action temperature is 45°C, and the pH is controlled between 8.5-11.5. Compared with the alkali method, the alkali-enzyme method increases the keratin yield from 24.4% to 58.1%, and the alkali dosage is reduced by 50%. The prepared keratin had high in vitro antioxidant activity, which provided a new idea for the resource utilization of bovine hair waste.

籾殻灰を用いた多孔質ジオポリマー硬化体の作製とその評価

Rice husk is a byproduct of rice production. Appropriate burning the husk produces the rice husk ash containing amorphous silica as a main component. Currently, the ash is expected as a biomass resource. In the present study, the rice husk ash was used to prepare potassium silicate solution. Geopolymer materials were synthesized by a reaction between the potassium silicate solution and metakaolin. In addition, Si powder and a dispersing agent were added to the geopolymer precursor paste to prepare a porous material, and its applicability as a heat insulating material was investigated. Assuming application to heat insulating materials, the effects of alkali concentration in the potassium silicate solution on the curing rate and density were investigated, and the thermal conductivity properties were evaluated. As a result, the curing rate of the geopolymer precursor increased with increasing alkali concentration of the potassium silicate solution. As the concentration increased, in addition, the bulk density and the thermal conductivity decreased. It was found that the heat insulation performance of the porous geopolymer is controlled by adjusting the alkali concentration in the potassium silicate solution.

Hot pad–batch dyeing of cotton fabrics using reactive blue-vinyl sulfone dye

Cold pad–batch dyeing of reactive dyes is low energy consumption and a clean dyeing technique. However, the room dyeing temperature requires strongly active base reactive dyes for dye fixation, bringing about the limitation of dye adaptability. Here, we propose a new technology of hot pad–batch dyeing that has the advantages of higher dye fixation and excellent color fastness. Three blue reactive dyers (C.I. Reactive Blue 19, C.I. Reactive Blue 21, C.I. Reactive Blue 203) that contain β-sulfate ethyl sulfone were used to increase the dye fixation of reactive dyes with cotton fibers. The effects of alkali concentration, dyeing temperature, batching time, and salt concentration on the dyeing performance of cotton fabrics were studied. The effects of post-treatment (soaping and fixation) on the K/ S values and color fastness were also investigated. The study showed that the dye fixation rate of the three reactive blue dyes was higher than 87%, and the rubbing and washing color fastness was more than grade 3–4 in the process of hot pad–batch dyeing of cotton fabrics. Furthermore, the dyed cotton fiber was fixed with a fixing agent (polyurethane (PU) and a mixture of PU and an aziridine crosslinker), and the color fastness reached not less than grade 4. Compared with cold pad–batch dyeing, hot pad–batch dyeing has the advantages of higher dye fixation and excellent color fastness for the three reactive blue dyes. Therefore, the dyeing performance of β-sulfate ethyl sulfone types of blue reactive dyes using hot pad–batch dyeing can effectively reduce the burden of post-treatment and the discharge of dyeing wastewater, and has a good application prospect in the dyeing of cotton fabrics.

Evaluation of porosity, mechanical and thermal properties of self-ignition coal gangue-based foams via fast microwave foaming

Recently, the large-scale stock and pollution of solid waste has become a serious environmental and economic problem. Upcycling the solid waste to produce porous materials is a value-added waste management method. Self-ignition coal gangue-based alkali-activated foams were successfully produced via a fast microwave foaming method within a few minutes. The effect of alkali concentration on pore structure, porosity, mechanical and thermal properties of alkali-activated foams was explored. Alkali-activated foams with low bulk density (0.41–0.81 g/cm3), high total porosity (65.6–83.5 vol%), acceptable compressive strength (0.92–4.42 MPa), and low thermal conductivity (0.11–0.14 W/mK) were obtained by a fast microwave foaming method. The foams showed excellent high temperature performance. The compressive strength showed an increasing trend after heat treatment from 500 to 1100 °C. Simultaneously, a low high-temperature volume shrinkage (4.0–4.1%) was achieved. The obtained foams can be used as high-performance proppant materials, thermal insulation building materials, and in fire-resistant applications.

Fine control for the preparation of ceria nanorods (111).

The morphologies and exposed surfaces of ceria nanocrystals are important factors in determining their performance. In order to establish a structure-property relationship for ceria nanomaterials, it is essential to have materials with well-defined morphologies and specific exposed facets. This is also crucial for acquiring high resolution 17O solid-state NMR spectra. In this study, we explore the synthesis conditions for preparing CeO2 nanorods with exposed (111) facets. The effects of alkali concentration, hydrothermal temperature and time, cerium source and oxidation agent are investigated and optimal synthesis conditions are found. The resulting CeO2 nanorods show very narrow 17O NMR peaks for the oxygen ions in the first, second and third layers, providing a foundation for future research on mechanisms involving ceria materials using 17O solid-state NMR spectroscopy.

The effect of alkali concentration on the properties of activated tungsten tailings

The 7d unconfined compressive strength tests of alkali-activated tungsten tailings and the microscopic characteristics tests of scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) were conducted to investigate the effect of alkali-solid ratio on the properties of alkali-activated tungsten tailings. The test results indicate that the unconfined compressive strength of alkali-activated tungsten tailings increased with the alkali-solid ratio. However, the strength decreases slightly when the alkali-solid ratio is 12%. The microstructures of the gels generated in the alkali-activated tungsten tailings are affected by the alkali-solid ratio. The details are as follows: the microstructure is honeycomb in low alkali-solid ratio (7%, 8% and 10%), with N-A-S–H as its primary form, and flocculation in high alkali-solid ratio (14% and 15%), mainly in the form of C-A-S–H. When the alkali-solid ratio is at the medium level (12%), the microstructure is a small round bead, and the N-A-S–H is equivalent to the C-A-S–H. The more C-A-S–H content, the greater the strength. This study can provide a scientific basis and technical reference for the resource utilization of tungsten tailings.

Physicochemical characterization, rheological and antioxidant properties of three alkali-extracted polysaccharides from mung bean skin

The properties of polysaccharides are closely related to their extraction and preparation methods. However, studies on the effect of alkali concentration on the properties of polysaccharides during alkali extraction are scarce. In this study, three alkali-extracted polysaccharides from mung bean skin (MBP) by different alkali concentrations (0.5%, 1.0%, 2.0%, w/v, MBP0.5, MBP1.0 and MBP2.0) were successfully obtained. The effects of alkali concentration on the extraction rate, microstructure, rheological properties, antioxidant activity and cell proliferation activity of MBP were investigated. The results showed that the alkali extraction method can break the ester and hydrogen bonds between polysaccharides, thus three alkali-extracted polysaccharides had higher extraction yields than polysaccharide extracted by hot water (MBPW), and MBP1.0 extraction rate of 3.64%. Moreover, comparing with MBPW, three alkali-extracted polysaccharides had lower molecular weights, particle sizes and better thermal stability. In addition, MBP0.5 had better antioxidant activity due to its higher galacturonic acid content and lower molecular weight, MBP1.0 and MBP2.0 had a tight structure, flat surface, resulting in a strong gel network structure. Cell experiments showed that MBPs had different degrees of proliferative effects on RAW264.7 and L-02. This study will provide some research ideas for the extraction of plant polysaccharides by alkaline methods.

Synthesis of kaliophilite from high calcium fly ash: Effect of alkali concentration

In recent years, the synthesis of zeolite-like products (such as kaliophilite) has been a hot spot due to its high thermal stability, which is excellent inorganic insulating filler and is expected to be widely applied in the field of fireproof materials. Therein, high calcium fly ash is applied to synthesize kaliophilite by hydrothermal method. The microstructure evolution of kaliophilite was investigated, and the effect of alkali concentration on the kaliophilite formation mechanism was analyzed by XRD, SEM, TG-DSC, FT-IR and 29Si NMR. The results showed that the synthesized kaliophilite presented high thermal stability, and the mass loss was low by 8.83 % at 1000 °C. Hydrothermal promoted the formation of kaliophilite that Q4(0Al), Q4(1Al), Q4(2Al), Q4(3Al) and crystal silicon turned into Q4(4Al) after hydrothermal transformation. Furthermore, alkali concentration played a key role in the hydrothermal transforming process that low alkali concentration below 8 mol/L had little effect on the synthesis of kaliophilite, while high alkali concentration (≥ 8 mol/L) contributed to the formation of kaliophilite.

GEP tree-based computational AI approach to evaluate unconfined compression strength characteristics of Fly ash treated alkali contaminated soils

The structural failures induced by alkali-contamination of soils are well established by earlier researchers. In the present study, the effect of alkali concentration (2 M and 4 M) and duration of curing on the unconfined compressive strength (UCS) of two types of soils (Kaolin and BC soil) were evaluated. Further, the effect of fly ash (FA) addition (10%, 15%, and 20%) on the UCS of alkali-contaminated soils was also determined. The results revealed that alkali contamination resulted in reducing UCS (by 36% and 46%), observed for kaolin and BC soil, respectively. The addition of FA has resulted in a linear increase in UCS of both soils. The optimum content was noted at 15%, attributed to the pozzolanic reaction initiated by alkali and subsequent gain of UCS with the formation of calcium (with FA addition) based hydration compounds. In addition, three attributes, i.e., FA content, curing period, and alkali concentration, have been used to develop GEP tree-based models to furnish simple prediction equations for calculating the UCS of Kaolin and BC soils. The accuracy of the developed models were initially validated using various statistical checks such as R, MAE, RMSE and RSE. For the 2nd level validation, parametric and sensitivity analyses were carried out for both soils, which yielded a comparable variation and contribution of each input conforming to the literature.

Assessment of Natural Cellulosic Powder from Pepper Pericarp Waste (Piper nigrum L.) after Alkalization and Bleaching Treatment: Effect of Alkali Concentration and Treatment Cycle

Pepper (Piper nigrum L.) pericarp is an agriculture waste in the production of white pepper. It is underutilised agro-industrial waste which could be a promising natural source of cellulose. Hence, finding an optimum way to remove the non cellulose components without degrading the cellulose structure is essential. In this work, the effects of alkaline concentration (4, 5, and 6% NaOH) and number of soaking cycle (3 & 4 cycles) on the characteristics of cellulose from pepper pericarp were investigated. The obtained cellulose powder was characterized for its yield, α-cellulose content, particle size, zeta potential, morphology, whiteness index, crystallinity degree and thermal stability. The white powder cellulose after 4th cycle treatment with 4% NaOH appeared to have the highest yield (23.63%), α-cellulose (65.97%), crystallinity structure (51%) and better thermal stability at 334 °C. FTIR spectrum at band around 1732 cm-1 indicates a partial removal of non-cellulosic material at all alkalization condition due to the presence of remaining lignin and hemicellulose. These may contribute to formation of negative surface charge on all cellulose samples which may potentially enhance the functionality of the material as emulsifier. Based on two-way ANOVA test, concentration and cycle of alkaline treatment significantly (p<0.05) influenced the yield, particle size and zeta potential, meanwhile α-cellulose significantly influence by NaOH concentration only (p<0.05). The findings showed that manipulating the synthesis condition of cellulose powder influenced its properties which could be further used in various applications.

Increasing hardwood kraft pulp yield using sodium methyl mercaptide

Abstract The objective of this work was to determine the effect of sodium methyl mercaptide (SMM) as an additive on the minimization of carbohydrate peeling reactions in Rock/Hard Maple (Acer saccharum) chips during kraft pulping. Two methods were evaluated for SMM addition to the pulping process: 1) pre-treatment before pulping and 2) co-addition with white liquor. The experimental results showed about 2.5% (on wood basis) increase in the kraft pulp yield after pre-treatment with 4.38% SMM (on wood basis) or the co-addition of the same amount of SMM with white liquor. The use of 4.38% SMM allowed a decrease in the white liquor effective alkali charge of 3% (on wood basis) to produce the target 14–15 kappa pulp. The 4.38% SMM charge was determined to be the optimum for both pre-treatment and co-addition. The increase in kraft pulp yield was mostly due to increased retention of cellulose (about 0.8% on wood) and xylan (about 1.8% on wood). The retention of glucomannan was insignificant in all cases. Based on the increase in intrinsic viscosity, it is concluded that the increased cellulose yield with SMM addition is caused by both reduced primary peeling and faster delignification rate (less alkaline hydrolysis followed by secondary peeling). The increased xylan retention is due to the lower effective alkali concentration during kraft pulping with SMM addition.

A novel process for synthesis of soybean protein hydrolysates and study of its effectiveness as a biostimulant and emulsifier

We study in extensive detail synthesis of protein hydrolysates (PHs) from soybean meal (SBM) using high shear stator-rotor impeller. The effects of alkali concentration, soaking and shearing time, SBM loading and combination of soaking and shearing on the extent of SBM hydrolysis and protein/amino acid concentration are elucidated. Effectiveness of soybean protein hydrolysates (SPHs) as a plant-based biostimulant and as an emulsifier for the synthesis of oil-in water emulsions was investigated. Use of a high shear mixer and alkaline conditions resulted in up to 80% extraction of protein in 30 min at room temperature. Amount of protein extracted increased with NaOH concentration, SBM loading and shear mixing time. However, alkali concentration and application of shear mixer were dominant factors for maximum SBM hydrolysis and protein extraction. SPHs showed excellent biostimulant activity for wheat and fenugreek plants. Wheat and fenugreek plants which received SPHs treatment showed enhanced percent germination, survival and overall growth of the plants (shoot and root length and dry weight). SPHs stabilised oil-in water emulsions showed excellent long-term stability and its emulsifying properties were comparable with the similar emulsions stabilised by soy protein isolates.

Efficient Swelling and Mercerization of Bagasse Fiber by Freeze-Thaw-Assisted Alkali Treatment

The mercerization of fiber is an important method for the high-value utilization of cellulose. In this study, the bagasse fiber was mercerized by freeze–thaw-assisted alkali treatment (FT/AT). The effects of freezing temperature, freezing time, alkali concentration, and thawing temperature on cellulose and hemicellulose removal were studied. The optimal freezing temperature was −40°C, freezing time was 8.0 h, alkali concentration was 5.0%, and thawing temperature was 30°C. The highest removal rate of hemicellulose was 75.64%. It was 5.80% higher than that of alkali treatment (AT). The alkaline degradation of cellulose was inhibited. The penetration of alkaline solution to fiber was promoted by the assistance of freeze-thaw pretreatment. The effective alkali concentration (5.0%) of cellulose I completely transformed into cellulose II decreased by 66.67% compared with traditional alkaline mercerization (15.0%). The high-efficiency mercerization of fiber was achieved by FT/AT. It provides theoretical support for promoting the high-value utilization of lignocellulosic biomass.