Alkaline Hydrogen Peroxide Treatment Research Articles

Alterations in physicochemical and functional properties of buckwheat straw insoluble dietary fiber by alkaline hydrogen peroxide treatment

To enhance the physicochemical and functional properties of insoluble dietary fiber (IDF) from buckwheat straw, we investigated the effects of alkaline hydrogen peroxide (AHP) treatment. Electron microscopy showed that the IDF had regular and compact tubes that turned into wrinkled lamellar products. After AHP treatment, X-ray diffraction indicated that the crystalline structure of the IDF was perturbed. And an undesirable decrease was observed in the content of hydroxybenzoic acid derivatives, hydroxycinnamic acid derivatives, flavonoids and the antioxidant capacity of IDF modified by AHP; however, the hydration properties (such as water holding capacity), α-amylase inhibition activity and glucose adsorption capacity of IDF were significantly enhanced by AHP. Furthermore, AHP led to a redistribution of monosaccharides in soluble dietary fiber and IDF, an interesting finding hinting at the mechanism and potential applications of AHP modification of IDF. In this study, AHP enhanced the physiological and functional properties of buckwheat straw IDF.

Effect of alkaline peroxide treatment on the chemical compositions and characteristics of lignocellulosic nanofibrils

Effects of alkaline peroxide (AP) treatment on chemical compositions and characteristics of lignocellulosic nanofibrils (LCNFs) were investigated. The AP treatment was conducted on a wood powder (Liriodendron tulipifera) at 80 °C for 1 or 5 h with different hydrogen peroxide concentrations (0.2 to 12 wt%) to selectively remove hemicelluloses and lignin. The treated wood powder was then defibrillated using wet-disk milling (WDM). The hemicelluloses and lignin in the LCNFs were successfully reduced to the ranges of 6.0% to 23.6% and 13.0% to 30.0%, respectively, depending upon the AP treatment conditions. The defibrillation efficiency improved as the hemicelluloses and lignin were removed, which reduced the LCNF dimensions. The filtration time increased with decreasing lignin and hemicellulose contents. The cellulose crystallinity and surface area of the LCNFs increased with decreasing lignin and hemicellulose contents. The tensile strength and water contact angles of the nanopaper handsheets increased, and the paper’s color became whiter as the lignin content decreased.

The effect of pH on surface activation of wood polymer composites (WPCs) with hydrogen peroxide for improved adhesion

Wood Polymer Composites (WPCs) have become widely acceptable for use in different products, including furniture. This range of applications could be increased by improvement in effective bonding and jointing techniques. However adhesion between WPC components is problematic because of their low surface energy and the hydrophobic nature of the polyolefin matrices which are commonly used. Surface activation pretreatments using hydrogen peroxide solutions have been investigated, and shown an improvement in lap-joint shear when bonding using epoxy adhesives. The effect on surface energy, roughness and chemical composition was studied. The improvement in adhesion appeared to be governed by the pH of the treatment solution, with clear differences being identified between treatments in acidic and alkaline media.The best results were achieved with a mild alkaline hydrogen peroxide treatment at a pH of 7.5 (37% improvement); however a mild acidic hydrogen peroxide treatment also showed a suitable level of adhesion improvement (29%, pH 6). In the alkaline medium it was found that the hydroperoxy anion was efficient in altering both the lignin and the hemicellulose component of the wood flour. It was necessary to limit the extent of wood particle degradation by the hydroperoxy anion, explaining the poor adhesion for treatments with pH 9 peroxide solution. This study indicates that mild (pH 7.5) alkaline treatment solution could be employed. In the acidic medium, the free radical based reaction processes dominated, and were likely to have altered the polypropylene matrix of the WPC material.

Activity and Structural Characteristics of Peach Gum Exudates

Polysaccharide fractions were prepared from peach gum exudates by treatments with alkaline hydrogen peroxide (AHP) and liquid hot water (LHW). The structural characteristics and activities of the polysaccharide fractions were comparatively studied. The results suggested that arabinogalactans substituted with xylose and uronic acids were the main structure of all polysaccharide fractions. AHP and LHW treatments introduced the degradation of the polysaccharides, reducing the molecular weight of polysaccharides from 182500 g/mol to 78450 g/mol and 68420 g/mol, respectively. The decreasement of molecular weights responded to the decrease of thermal stability of polysaccharide fractions. However, AHP and LHW treatments removed most of the nonsugar composition, increasing the DPPH•- and ABTS•+-scavenging activity of polysaccharides. Polysaccharide fractions obtained from LHW treatment showed favorable DPPH•- and ABTS•+-scavenging activity at 22.9% and 34.3%, respectively, at concentration of 1000 μg/mL.

Alkaline Peroxide and Laccase Treatment for the Delignification of Ricinus Communis Biomass to Enhance Saccharification

Alkaline Peroxide and Laccase Treatment for the Delignification of Ricinus Communis Biomass to Enhance Saccharification

Isolation and characterization of microcrystalline cellulose from pomelo peel

In this study, cellulose from pomelo peel (PP-C) was isolated using alkaline hydrogen peroxide liquor extraction, and PP-C was further hydrolyzed by hydrochloric acid to yield microcrystalline cellulose (PP-MCC). Several analytical methods were used to determine the structural characteristics, crystalline behavior, morphological properties, thermal properties, and water/oil binding capacity of PP-C and PP-MCC. Fourier-transform infrared spectra and morphological analysis showed that the alkaline hydrogen peroxide treatment and acid hydrolysis successfully removed hemicellulose and lignin from pomelo peel fibers. Both PP-C and PP-MCC had only a cellulose I polymorph structure, and the crystallinity index of PP-MCC increased compared with that of PP-C. The degradation temperatures of PP-C and PP-MCC were approximately 257 °C and 280 °C, respectively. The water/oil binding capacity of PP-MCC was significantly higher than that of the commercial MCC. Our results thus suggested that PP-MCC might be suitable for use as a food stabilizer and pharmaceutical additive.

Exploring the composition of raw and delignified Colombian fique fibers, tow and pulp

As worldwide agricultural production rises, agro-industrial biomass becomes an abundant raw source for uses in energy and materials production. In Colombia fique plants (Furcraea spp.) are traditionally used to extract hard cellulosic fibers using mechanical decortication. Juice, pulp and tow, the by-products of this process, represent almost 95% of the fique leaf weight and are produced in large quantities. Data on these materials is scarce and greatly needed to guide and fuel fique agro-industrial development in Colombia. In this contribution we study the physicochemical properties of fique fibers and by-products (tow and pulp), before and after alkaline hydrogen peroxide treatment (AHP), using spectroscopic and microscopic techniques. Raw/clean fique tow is similar in structure and composition to fique fibers with average cellulose, hemicellulose and lignin contents of 52.3, 23.8 and 23.9%; in this by-product cellulose exists as a highly ordered structure with crystallinity index of 57%. Raw/clean fique pulp, composed of cellulose filaments from secondary cell walls and leaf epidermis, has average cellulose, hemicellulose and lignin contents of 30.5, 29.7 and 9.6%, with cellulose exhibiting an amorphous structure with a crystallinity index of 35%. The AHP treatment of these by-products effectively removed non-cellulosic compounds such as hemicellulose and lignin. After AHP lignin content in fique tow decreases to 2.8% while cellulose crystallinity increases up to 73%, Likewise, fique pulp shows a reduction in lignin to 2.1% and an increase in cellulose crystallinity up to 47%. IR spectroscopic analysis, after AHP, show a decrease of signals attributed to hemicellulose and lignin and FESEM images show a disruption of the lamellar structure in the macro fiber by the removal of hemicellulose, lignin and ground tissue, leaving cellulose fibrils exposed. As the first in-depth report on fique by-products characterization, our results indicate that pulp and tow are interesting lignocellulosic materials due to their significant content of crystalline and amorphous cellulose.

Comparison of Pretreatment Methods on Vetiver Leaves for Efficient Processes of Simultaneous Saccharification and Fermentation by Neurospora sp.

Lignocellulosic biomass is a potential raw material for bioethanol production. Neurospora sp. can be used to convert lignocellulosic biomass into bioethanol because of its ability to perform simultaneous saccharification and fermentation. However, lignin content, degree of polymerization, and crystallinity of cellulose contained in lignocellulosic biomass can inhibit cellulosic-biomass digestion by Neurospora sp, so that a suitable pretreatment method of lignocellulosic biomass is needed. The focus of this research was to investigate the suitable pretreatment method for vetiver leaves (Vetiveria zizanioides L. Nash) used as a raw material producing bioethanol in the process of simultaneous saccharification and fermentation (SSF) by Neurospora sp.. Vetiver plants obtained from Garut are deliberately cultivated to produce essential oils extracted from the roots of this plant. Since the vetiver leaves do not contain oil, some of harvested leaves are usually used for crafts and cattle feed, and the rest are burned. This study intended to look at other potential of vetiver leaves as a source of renewable energy. Pretreatments of the vetiver leaves were conducted using hot water, dilute acid, alkaline & dilute acid, and alkaline peroxide, in which each method was accompanied by thermal treatment. The results showed that the alkaline peroxide treatment is a suitable for vetiver leaves as indicated by the increase of cellulose content up to 65.1%, while the contents of hot water soluble, hemicellulose, lignin, and ash are 8.7%, 18.3%, 6.8%, and 1.1%, respectively. Using this pretreatment method, the vetiver leaves can be converted into bioethanol by SSF process using Neurospora sp. with a concentration of bioethanol of 6.7 g/L operated at room temperature.

Isolation of cellulose and hemicellulose by using alkaline peroxide

Fall leaves are biodegraded and composted naturally in forests but they are wastes for urban areas. Moreover, they are widely available cellulose sources but have limited applications. Alkaline peroxide treatment of bioresources is one of the most widely studied clean methods for both delignification and hemicellulose removal but there is no study about application of that method on fall leaves at room temperature. In this study, the effect of alkaline peroxide treatment of fall leaves at room temperature on hemicellulose recovery and cellulose delignification were investigated. Fall leaves (FL) were treated with 0.3-3.0 M NaOH + 0-3 M H2O2 at room temperature. Hemicellulose recovery and cellulose delignification values were analyzed. Hemicellulose recovery and cellulose delignification increased and yield decreased by increasing NaOH and H2O2 concentrations. Hemicellulose recovery and cellulose delignification reached to the maximum levels, 99.5% and 81.6% respectively, at 3M NaOH + 3M H2O2 treatment condition. The end products were confirmed by analytically, spectrally and morphologically. Wasted fall leaves were turned into useful hemicellulose and cellulose products by using clean alkaline peroxide treatment at room temperature. The products can be further processed by known methods into other industrial products.

Study of time reaction on alkaline pretreatment applied to rice husk on biomass component extraction

Rice husk (RH) residue was submitted to a sequence of experimental procedures, specifically to investigate the reaction time influence of NaOH pretreatment on the extraction of silica, hemicellulose, and lignin components. In order to follow the extraction of each non-cellulosic components of rice husk, techniques such as Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction analysis, and scanning electron microscopy were performed on untreated RH and samples collected from the NaOH reaction media at several different reaction times, as well as the sample after alkaline-peroxide treatment. Under the process parameters used in the present study, the results showed that a great part of hemicellulose and silica contents was removed during the first 30 min of reaction time in NaOH pretreatment. Although there is evidence that NaOH pretreatment also removed some lignin content, the complete delignification process was more effective just after alkaline-peroxide reaction, which produced material rich in type I cellulose.

3-3-4 稲わらの熱分解および酵素糖化に対するアルカリ過酸化水素処理の効果

3-3-4 稲わらの熱分解および酵素糖化に対するアルカリ過酸化水素処理の効果

Short-time alkaline peroxide pretreatment for rapid pulping and efficient enzymatic hydrolysis of rice straw

To improve utilization of agricultural residues in biorefineries, the effects of alkaline peroxide (AP) pretreatment on thermal degradation and enzymatic digestibility of rice straw were investigated. A high-cellulose (>70%) pulp with a width of a few micrometers was obtained by rapid (10min) treatment with AP, without prior heating or other treatment. Moreover, enzymatic hydrolysis of the pulp produced a high glucose yield (approximately 80%). Microfibril networks were exposed, and many nano-scale pores that are easily penetrated by cellulases were observed on the surface of the AP-treated sample. For enzymatic hydrolysis of the pulp, increasing the dosage of cellulases was more effective for improving the glucose yield than addition of a grinding treatment. This AP treatment has the potential for on-site application because it is simple, highly efficient, and can be performed in a short time.

Optimization of the Strength Properties of Waste Oil Palm (Elaeis Guineensis) Fronds Fiber

ABSTRACTIn this study, Box-Behnken design (BBD) and response surface methodology (RSM) was applied to study the effects of alkaline peroxide treatment variables (cooking time, sodium hydroxide concentrations, and hydrogen peroxide concentrations) on the pulp and paper strength properties (screened pulp yield, kappa number, tensile index, tear index, burst index), which are considered dependent variables or response variable of the extracted cellulose from oil palm (Elaeisguineensis) fronds (OPF) vascular bundle fibers. The results indicated that at the optimum operating conditions of 2.35% NaOH, 5.00% H2O2 and a 53.41 min cooking time, resulting maximum strength properties (tensile index, burst index, tear index,) gave 9.92 Nm/g, 6.55 KPam2/g, 6.22 mNm2/g, respectively. The study revealed that alkaline peroxide pulped fibers of oil palm frond vascular bundles could be considered a suitable alternative for paper qualities with moderate strength requirements.

Characterization of dietary fiber from coffee silverskin: An optimization study using response surface methodology

Coffee silverskin dietary fiber (DF) was obtained by alkaline hydrogen peroxide (AHP) extraction procedure. Response surface methodology was used to study the effect of temperature (25, 40, & 55°С), hydrogen peroxide (HP) concentration (2, 6, & 10% v/v), pH (9, 10, 11,& 12), and time (1, 6, 12, 18, & 24h) of AHP treatment on loss, protein removal (PR), cellulose content, whiteness index (WI), water holding capacity (WHC) and oil holding capacity (OHC). AHP treatment (extraction time 18h, extraction temperature 25°С, HP concentration 6%v/v, & pH 12) enhanced the cellulose content of CS from 34–67.4%. The desirability function approach which used to perform multiple optimizations was 0.89, indicating the distance of the lower and upper limits relative to the actual optimum was highly suitable. The optimum isolation conditions were: extraction time 9.25h, extraction temperature 37.34°C, HP concentration 10%v/v, & pH 10.54. At optimum condition, WI, WHC, OHC, loss, & PR of DF were 80.30, 8.18 & 5.27, 40.05, 89.04%, respectively. The results suggested CS could be used as a source of insoluble DF especially cellulose in food formulations.

Comparison of chemical treatment methods for loblolly pine to utilize as enzyme hydrolyzate feedstock

The ground pine wood chips (GPWC) were examined through chemical treatment methods employing alkaline hydrogen peroxide treatment (AHP, consisted of 50 g L−1 potassium hydroxide, and 50 g L−1 hydrogen peroxide with added water at 78 °C for 24 h), and ethyl-hydro-oxides treatment (EHOs, consisted of 60% ethanol (of total solution), 50 g L−1 potassium hydroxide, and 50 g L−1 hydrogen peroxide with added water at 78 °C for 24 h). The effects of chemical treatments on GPWC were examined through combination of chemical composition followed by enzymatic hydrolysis (using Accellerase® 1500). The application of EHOs treatment removes the foaming issue that currently occurs due to AHP treatment at the elevated temperature. A removal of the foaming phenomenon increased the enzymatic glucan conversion (>70%) which is important in increasing the efficiency of biorefinery. The interaction of different variables in EHOs solvent formulations including ethanol concentration (0–60%), potassium hydroxide concentration (0–50 g L−1), hydrogen peroxide concentration (0–50 g L−1), and processing temperature (38 °-78 °C) were analyzed through four variables response surface methodology using glucan conversion and total polysaccharide conversion as responses. The glucan conversion and total polysaccharide conversion were analyzed to determine the specific and overall effects of Accellerase® 1500 on the amorphous polysaccharide contents of GPWC resulted through EHOs treatment formulations, respectively. The implications of all these findings are discussed with the available literature.

Alkaline hydrogen peroxide treatment for TiO2 nanoparticles with superior water-dispersibility and visible-light photocatalytic activity

Alkaline hydrogen peroxide treatment was proposed as a simple and green way to improve the performance of commercial TiO2 powder for water-dispersibility and visible-light photocatalytic activity on the degradation of dye pollutants. The performance of treated TiO2 was evaluated as a function of NaOH concentration, H2O2 concentration, and treatment time. The optimal conditions were determined to be 24 h in 100 mM H2O2 and 8 M NaOH. The treated samples were characterized by Raman spectroscopy, high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and ultraviolet–visible spectrophotometry. The analysis revealed that the crystal structure, morphology, and absorption band gap were retained, but the surface of the treated TiO2 was dramatically changed. The treated TiO2 was highly dispersible with a uniform hydrodynamic size of 41 ± 12 nm and stable over months in water at pH 3 without any stabilizing ligand and could significantly enhance the visible-light photodegradation of dye pollutants. The superior performance might be attributed to the formation of abundant surface hydroxyl groups. This treatment paves the way for developing water-dispersible TiO2 with superior visible-light induced photocatalytic degradation of dye pollutants without any complicated and expensive surface modification.

국내산 소나무로 제조된 APMP 특성 연구

ABSTRACT http://dx.doi.org/10.7584/ktappi.2016.48.1.100Journal of Korea TAPPIVol. 48. No. 1, 2016, 100-110pISSN (Print): 0253-3200Printed in Korea • 경상대학교 농업생명과학대학 환경재료과학과/임산공학과(Dept. of Env. Material Sci., IALS, Gyeonsang National Uni-versity, 660-701, Korea)† 교신저자(Corresponding Author): E-mail: jameskim@gnu.ac.kr Alkaline Peroxide Mechanical Pulping (APMP) of Pinus densiflora harvested from domestic mountains was explored. APMP contributes to various advantages including pulp quality, elimination of the need for a bleaching process, and energy savings. Sequential treat-ment of impregnation of bleaching chemicals and refining not only overcome the concern of alkaline darkening of wood chips during chemical impregnation, but it also brightens the chips to the desired brightness levels suitable for writing and printing papers. APMP pulping from Pinus densiflora was greatly influenced by the dosage levels of hydrogen peroxide and sodium hydroxide. Alkaline peroxide treatment was carried out by applying one of three levels of hydrogen peroxide (1.5, 3, and 4.5% based on the oven-dried weight of the wood chips) and one of three levels of sodium hydroxide (1.5, 3, and 4.5% based on the oven-dried weight of the wood chips). Other chemicals including a peroxide stabi-lizers and metal chelation were constantly added for all treatments. Chemical treatment with a liquor-to-wood ration of 9:1 was carried out in a laboratory digestor. Compared to BTMP, APMP pulping displayed outstanding characteristics including the less require-ment of refining energy, the better improvement of tensile strength, the more reduction of shives, and the greater increase of pulp brightness. In particular, when 4.5% of hy-drogen peroxide with impregnation during 90 minutes was used, the brightness of APMP reached 64.9% ISO. Even though bulk of APMP was decreased with the increase of sodium hydroxide, a better and improved balance could be achieved between optical and strength properties. The spent liquor obtained from the discharge of the impregnation process at

Pilot-Scale Investigation into the Effects of Alkaline Peroxide Pre-Treatments on Low-Consistency Refining of Primary Refined Softwood TMP

Primary refined coarse softwood thermomechanical pulp was treated with alkaline peroxide prior to low-consistency (LC) refining. The effects of the pre-treatments on pulp quality, refinability, and electrical energy consumption were assessed. Four pre-treatments were conducted with alkali charges of 2.5 and 6% and peroxide charges of 3 and 4%. The pulps were refined to specific energies up to 600 kWh/t by multiple passes through an LC refiner at intensities of 90 and 150 kWh/t. It was found that alkaline peroxide treatments increased tear strength and protected the fibre from cutting, especially during high intensity refining below a specific energy of 300 kWh/t. Treatment with 6% NaOH and 4% or 3% H2O2 led to lower brightness gains and scattering coefficients but increased the tensile strength index by 31%, potentially lowering the total electrical energy required to achieve strong pulp. The enhancement of tensile strength caused by the highly alkaline peroxide mostly resulted from increased bonding, which was attributable to acid group generation rather than the promotion of further fibrillation during LC refining.

Effects of Supplementary Alkali after Alkaline Peroxide Treatment on the Properties of Bleached Kraft Pine Fluff Pulp

Effects of dual-treatment on cellulose fiber quality, micro-structure appearance, crystalline structure, hydrogen bonds, and surface elements were analyzed using a fiber quality analyzer (FQA), scanning electron microscope (SEM), wide-angle X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS), respectively. In comparison to the untreated pulp, the brightness of pulp increased by 51.71%, whereas the apparent density and burst strength index of the pulpboard decreased by 11.76% and 48.18%, respectively. The absorption time, absorbability, and bulk of the fiber obtained by defibering the pulpboard decreased by 47.40%, 8.33%, and 5.32%, respectively, when it had been subjected to supplementary alkali. With the analysis of FQA and SEM, fiber swelled and curled, its surface was relatively smooth, and filaments of its partial surface area were exposed as a result of the supplementary alkali. Additionally, XRD analysis, FT-IR analysis, and XPS scanning spectra all showed that the crystallinity degree of fiber decreased by 45.10%, indicating more crystal structures were converted into amorphous structures. The proportion of total intra-molecular hydrogen bond intensity to total hydrogen bonds increased. The –OH content on fiber surface only decreased by 4.15%, compared with those of the untreated pulp, when the fiber was subjected to the two-step chemical treatment.

Delignification of vineyard pruning residues by alkaline peroxide treatment

Vineyard pruning residues were subjected to alkaline peroxide treatment for delignification. Experimental conditions maximizing lignin removal were determined by using Box–Behnken statistical experiment design. NaOH/Biomass, H2O2/Biomass and retention time were chosen as independent variables and percent lignin removal was the objective function. Experiments were done at constant Solid/Liquid ratio of 0.1 (w/w) and 135°C. All parameters were found to have significant effect on lignin removal. Complete delignification was obtained in 120min at a NaOH/Biomass ratio of 1.10 and a H2O2/Biomass ratio of 0.65. The solid residue consisted of 95% total carbohydrate indicating significant carbohydrate enrichment after complete delignification.