Effect of Fenton pretreatment on enzymatic hydrolysis of poplar

BioResources ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. 1980-1987
Author(s):  
Shujie Wang ◽  
Jin Sun ◽  
Mengjie Chen ◽  
Xianfeng Hou ◽  
Zhenzhong Gao

The Fenton reaction has been widely used in the pretreatment of lignocellulose. It offers the advantages of simple operation, fast reaction speed, and low pollution. In this study, the effects of different proportions of Fenton reagents on the enzymatic hydrolysis of poplar were compared and analyzed, and the optimal ratio of Fenton reagents was obtained. The maximum yield of enzymatic hydrolysis of glucose in Fenton pretreatment samples was 406 mg/g at H2O2 and Fe2+ concentrations of 1.0 mol/L and 0.01 mol/L, respectively, which was 2.5 times that of untreated samples. Meanwhile, the composition analysis and FT-IR analysis showed that Fenton pretreatment could degrade lignin and hemicellulose effectively. X-ray diffraction (XRD) analysis showed that Fenton pretreatment can partially destroy the amorphous region of poplar. These findings will contribute to efforts to improve the viability of the Fenton pretreatment process for converting biomass into energy.

2021 ◽  
Vol 37 (6) ◽  
pp. 648-658
Author(s):  
Ji Won Kim ◽  
Se Rin Park ◽  
Ki Ok Han ◽  
Seon Hwa Jeong

In this study, we aimed to analyze the chemical changes that occur in Korean paper in an accelerated deterioration environment of 105℃. We selected the Korean paper produced with different types of cooking agents (plant lye, Na2CO3) and during different manufacturing seasons (winter, summer). The degree of deterioration of the Korean paper was confirmed by measuring the brightness, yellowness, and pH level, and the degree of change in each vibrational region of cellulose as deterioration progressed through infrared (FT-IR) spectroscopy. The FT-IR analysis showed that, as deterioration progressed, the absorbance of the amorphous region in cellulose decreased, whereas the absorbance of the crystalline region slightly increased. X-Ray diffraction (XRD) analysis and Raman spectroscopy were performed to verify the changes in the crystalline and amorphous regions in cellulose indicated by the FT-IR results. Furthermore, the crystallinity index (CI) was calculated; it showed a slight increase after deterioration; therefore, CI was confirmed to follow the same trend as that observed for absorbance in the FT-IR results. In addition, as a result of Raman spectroscopic analysis, the degree of decomposition of the amorphous region in the cellulose under the manufacturing conditions was confirmed by the fluorescence measured after the deterioration.


TAPPI Journal ◽  
2011 ◽  
Vol 10 (1) ◽  
pp. 17-23
Author(s):  
KEVIN TAYLOR ◽  
RICH ADDERLY ◽  
GAVIN BAXTER

Over time, performance of tubular backpulse pressure filters in kraft mills deteriorates, even with regular acid washing. Unscheduled filter replacement due to filter plugging results in significant costs and may result in mill downtime. We identified acid-insoluble filter-plugging materials by scanning electron microscope/energy-dispersion X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) analysis in both polypropylene and Gore-Tex™ membrane filter socks. The major filter-plugging components were calcium sulfate (gypsum), calcium phosphate (hydroxylapatite), aluminosilicate clays, metal sulfides, and carbon. We carried out detailed sample analysis of both the standard acid-washing procedure and a modified procedure. Filter plugging by gypsum and metal sulfides appeared to occur because of the acid-washing procedure. Gypsum formation on the filter resulted from significant hydrolysis of sulfamic acid solution at temperatures greater than 130°F. Modification of the acid-washing procedure greatly reduced the amount of gypsum and addition of a surfactant to the acid reduced wash time and mobilized some of the carbon from the filter. With surfactant, acid washing was 95% complete after 40 min.


Author(s):  
Erdoğan Karip ◽  
Mehtap Muratoğlu

People are exposed to different kinds of diseases or various accidents in life. Hydroxyapatite (HA) has been widely employed for bone treatment applications. In this study, HA was extracted from sheep bones. Bio-composites were doped with 1, 5, and 10 wt.% of expanded perlite and 5 wt.% of ZrO2–MgO-P2O5. The bio-composites were prepared by the cold isostatic pressing method (250 MPa) and sintered at 900°C for 1 h. In order to evaluate the characteristics of the bio-composites, microhardness, density, X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses were carried out on them. Additionally, the specimens whose characteristics were determined were kept in synthetic body fluid (SBF), and their in vitro behavior was examined. As a result, it was observed that microhardness increased as both the weight and the grain size of the expanded perlite were increased. Calcium silicate, tri-calcium phosphate, and hydroxyapatite were observed in the XRD analysis of all samples, and the formation of apatite structures was increased by addition of ZrO2–MgO–P2O5.


2006 ◽  
Vol 118 ◽  
pp. 639-644
Author(s):  
Hye Sung Kim ◽  
Su Chak Ryu

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) powders is synthesized using the mixed powders of CaCO3 refined from oyster shells and phosphoric acid (H3PO4-98%, Daejung) as starting materials. The characteristic evaluation and chemical analysis of the synthesized powders is performed by X-ray diffraction (XRD), Fourier-transformed infra-red spectroscopy (FT-IR), and inductively-coupled plasma atomic emission spectroscopy (ICPAES). XRD analysis of synthetic powder by heat treatment at 1300°C for 2hrs shows only HAp peaks corresponding to stoichiometric HAp. It is confirmed by ICP-AES test that impurities such as Zn, In, Ti, Ba, Cd, Pb, and Mn, is not detected at all, but small amounts of Ti and Be is observed (0.099ppm Ti and 0.002ppm Ba). Variation of bone density is measured by giving medication of HAp powder with drinking water into human body continuously for three month. After the medication, the bone density is higher than the medication before. This means that HAp powder made from this process can be used as improver of bone density.


1970 ◽  
Vol 46 (3) ◽  
pp. 375-378 ◽  
Author(s):  
MM Islam ◽  
SM Masum ◽  
MM Rahman ◽  
AA Shaikh

The present investigation described the effective preparation of glucosamine hydrochloride (GluHCl) from chitin which was extracted from indigenous shrimp shell. GluHCl has attracted much attention owing to its therapeutic activity in osteoarthritis and widely used dietary supplement. The key step involved was extraction of chitin from shrimp skeleton and then hydrolysis of chitin by concentrated hydrochloric acid. The reaction proceeds via break down of glycoside linkage. Structural analysis was carried out by melting point, TLC, FT-IR, elemental analysis and all the data were compared with that of standard GluHCl. The elemental (C, 32.75; H, 6.51; N, 6.20) analysis is good concord with the calculated value (C, 33.42; H, 6.54; N, 6.50). Absence of v max at 1726 cm-1 indicates that GluHCl is a deacetylated product of chitin. The yields of the product mainly depend on reaction conditions. Maximum yield (63.5%) was obtained when chitin was hydrolyzed with concentrated HCl for 1.30 h. Key words: Shrimp shell; Chitin, Acid hydrolysis; Glucosamine hydrochloride Osteoarthritis. DOI: http://dx.doi.org/10.3329/bjsir.v46i3.9046 BJSIR 2011; 46(3): 375-378


2007 ◽  
Vol 43 (1) ◽  
pp. 21-28 ◽  
Author(s):  
C. Tang ◽  
Y. Du ◽  
H. Xu ◽  
S. Hao ◽  
L. Zhang

To ascertain whether the liquid miscibility gap exists in the Ce-Mn system, 3 key alloys are prepared by arc melting the pure elements, annealed at specified temperature for 20 minutes, quenched in ice water and then subjected to X-ray diffraction (XRD) analysis for phase identification and to scanning electron microscopy (SEM) with energy dispersive X-ray analysis for microstructure observation and composition analysis. The XRD examination indicated that terminal solutions based on Ce and Mn exist in the water-quenched alloys. No compound was detected. Microstructure observation and composition analysis indicate the nonexistence of the liquid miscibility gap. The newly assessed Ce-Mn phase diagram was presented. .


2016 ◽  
Vol 46 (6) ◽  
pp. 778-790 ◽  
Author(s):  
Ghassan Abo Chameh ◽  
Fadi Kheder ◽  
Francois Karabet

Purpose The purpose of this paper was to find out the appropriate enzymatic hydrolysis conditions of alkali pretreated olive pomace (OP) which enable maximum yield of reducing sugar. Design/methodology/approach The commercial enzymatic preparation (Viscozyme® L) was used for the hydrolysis of OP. The effects of pretreatment, time, temperature, pH, enzyme quantity and substrate loading on the hydrolysis yield were investigated. Findings This study showed that enzymatic hydrolysis of OP using Viscozyme® L can be successfully performed at 50°C. Alkaline pretreatment step of OP prior the enzymatic hydrolysis was indispensable. The hydrolysis yield of alkaline pretreated OP was 2.6 times higher than the hydrolysis yield of untreated OP. Highest hydrolysis yield (33.5 ± 1.5 per cent) was achieved after 24 h using 1 per cent (w/v) OP load in the presence of 100 μl Viscozyme® L at 50°C and pH 5.5 with mixing rate of 100 rpm (p = 0.05). Originality/value Reaction time, temperature, pH value and enzyme quantity were found to have a significant effect on enzymatic hydrolysis yield of alkali pretreated of OP. Although high-solid loadings of OP lowered the hydrolysis yield, it produced higher concentration of reducing sugars, which may render the OP conversion process more economically feasible.


1963 ◽  
Vol 41 (1) ◽  
pp. 719-730 ◽  
Author(s):  
Paul J. Fritz ◽  
Paul Melius

A new preparation of hog pancreatic lipase is described which is evidently the most stable one of its kind. From the composition of the reaction mixtures after enzymatic hydrolysis with and without sodium taurocholate, it appears that the hydrolysis of triglyceride to diglyceride is facilitated and the hydrolysis of diglyceride to monoglyceride is depressed in the presence of taurocholate. The differences in the curves showing the rates of hydrolysis of triolein, monoolein, tributyrin, and monobutyrin in the presence and absence of taurocholate also indicate that the taurocholate acts to split the diglyceride–enzyme complex and thus increases the action of the enzyme on the triglyceride ester. The hydrolysis of the triglyceride is a fast reaction whereas the di- and mono-glycerides are hydrolyzed at much slower rates. The activation energy for the lipolysis of the triolein and tributyrin has been calculated in the presence and absence of taurocholate. This was possible because in spite of earlier reports that the lipolysis of triolein was not temperature dependent between 10 and 40 degrees, we found these reactions to be temperature dependent. The lesser activating effect at the highest taurocholate concentrations indicates this is not a simple emulsifying effect.


2020 ◽  
Vol 977 ◽  
pp. 195-200
Author(s):  
Hong Tham Thi Nguyen ◽  
Dao Thi To Uyen ◽  
Duy Chinh Nguyen ◽  
Van Thuan Tran ◽  
Tri Duc Lam ◽  
...  

We investigated the fabrication of Ca/Al layered double hydroxide (LDHs) via a one-step hydrothermal approach with slow hydrolysis of urea at a low temperature without further annealing required. The as-synthesized Ca/Al LDHs nanostructures obtained were defined using Fourier transforms infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results demonstrated that Ca/Al LDHs exhibit excellent adsorption performance on Congo red anionic dyes in aqueous solution. The adsorption capacity of the Ca/Al LDHs toward Congo red was found to be 59.41 mg/g.


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