Characterization of Bio-Oil Obtained from Sewage Sludge Pyrolysis Catalyzed by Char

The pyrolysis of sewage sludge (SS) in the presence of sewage sludge pyrolysis char (SSC) as catalyst was conduct in a horizontal reactor at 500°C. Gas chromatography-mass spectroscopy (GC-MS), element analysis, high heating value (HHV) analysis, water content analysis and gel permeation chromatography (GPC) were used to characterize the pyrolysis oil. The declined char yields with increased SSC mix ratio (MR) indicated that SSC could promote the devolatilization reaction. Meanwhile the declined top phase oil (TPO) yield and increased bottom phase oil (BPO) and gas yield showed that crack reaction may happen catalyzed by SSC. According to the result of GC-MS, aliphatics and steroids content drops apparently since MR increased to 50 wt.%, while aromatic compounds and phenols content increased at the same time. Element analysis showed an apparent transportation of hydrogen and oxygen from TPO to BPO. HHV of TPO decreased with MR increased. The result of GPC indicated that increased MR caused continuing decreased average molecular weight of TPO. Consequently, the increased SSC addition could promote the devolatilization and large molecular compounds catalysis crack of sewage sludge.

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Probing the molecular weights of sweetgum and pine kraft lignin fractions

TAPPI Journal ◽

10.32964/tj20.6.381 ◽

2021 ◽

Vol 20 (6) ◽

pp. 381-391

Author(s):

JULIANA M. JARDIM ◽

PETER W. HART ◽

LUCIAN LUCIA ◽

HASAN JAMEEL

Keyword(s):

Molecular Weight ◽

Black Liquor ◽

Average Molecular Weight ◽

Gel Permeation Chromatography ◽

Systematic Investigation ◽

Kraft Pulping ◽

Molecular Weights ◽

Lignin Recovery ◽

Lignin Reactivity ◽

Kinetics Of

The present investigation undertook a systematic investigation of the molecular weight (MW) of kraft lignins throughout the pulping process to establish a correlation between MW and lignin recovery at different extents of the kraft pulping process. The evaluation of MW is crucial for lignin characterization and utilization, since it is known to influence the kinetics of lignin reactivity and its resultant physicochemical properties. Sweetgum and pine lignins precipitated from black liquor at different pHs (9.5 and 2.5) and different extents of kraft pulping (30–150 min) were the subject of this effort. Gel permeation chromatography (GPC) was used to deter- mine the number average molecular weight (Mn), mass average molecular weight (Mw), and polydispersity of the lignin samples. It was shown that the MW of lignins from both feedstocks follow gel degradation theory; that is, at the onset of the kraft pulping process low molecular weightlignins were obtained, and as pulping progressed, the molecular weight peaked and subsequently decreased. An important finding was that acetobromination was shown to be a more effective derivatization technique for carbohydrates containing lignins than acetylation, the technique typically used for derivatization of lignin.

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Characterisation of Sequential Solvent Fractionation and Base-catalysed Depolymerisation of Treated Alkali Lignin

BioResources ◽

10.15376/biores.10.3.4137-4151 ◽

2015 ◽

Vol 10 (3) ◽

pp. 4137-4151 ◽

Cited By ~ 5

Author(s):

Aikfei Ang ◽

Zaidon Ashaari ◽

Edi Suhaimi Bakar ◽

Nor Azowa Ibrahim

Keyword(s):

Molecular Weight ◽

Chemical Structure ◽

Average Molecular Weight ◽

Gel Permeation Chromatography ◽

Solubility Parameters ◽

Low Molecular Weight ◽

Sequential Fractionation ◽

Weight Average Molecular Weight ◽

Solvent Fractionation ◽

Alkali Lignin

An alkali lignin (OL) with a weight-average molecular weight (Mw) of 11646 g/mol was used to prepare low-molecular weight lignin for resin synthesis. The low-molecular weight lignin feedstock was obtained via base-catalysed depolymerisation (BCD) treatments at different combined severity factors. Sequential fractionation of the OL and BCD-treated lignins using organic solvents with different Hildebrand solubility parameters were used to alter the homogeneity of the OL. The yield and properties of OL itself and OL and BCD-treated OL dissolved in propan-1-ol (F1), ethanol (F2), and methanol (F3) were determined. Regardless of the treatment applied, a small amount of OL was dissolved in F1 and F2. The BCD treatment did not increase the yield of F1 but did increase the yields of F2 and F3. Gel permeation chromatography (GPC) showed that the repolymerization reaction occurred in F3 for all BCD-treated OL, so these lignins were not suitable for use as feedstocks for resin production. The GPC, 13Carbon-nuclear magnetic resonance, and Fourier transform infrared spectroscopy analyses confirmed that the F3 in OL exhibited the optimum yield, molecular weight distribution, and chemical structure suitable for use as feedstocks for resin synthesis.

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Characterization of bi-layered magnetic nanoparticles synthesized via two-step surface-initiated ring-opening polymerization

Pure and Applied Chemistry ◽

10.1515/pac-2015-0607 ◽

2015 ◽

Vol 87 (11-12) ◽

pp. 1085-1097 ◽

Cited By ~ 2

Author(s):

Li Wang ◽

Stefan Baudis ◽

Karl Kratz ◽

Andreas Lendlein

Keyword(s):

Magnetic Nanoparticles ◽

Ring Opening ◽

Average Molecular Weight ◽

Polymer Networks ◽

Gel Permeation Chromatography ◽

Degree Of Crystallinity ◽

Scanning Calorimetry ◽

H Nmr ◽

Transmission Electron

AbstractA versatile strategy to integrate multiple functions in a polymer based material is the formation of polymer networks with defined nanostructures. Here, we present synthesis and comprehensive characterization of covalently surface functionalized magnetic nanoparticles (MNPs) comprising a bi-layer oligomeric shell, using Sn(Oct)2 as catalyst for a two-step functionalization. These hydroxy-terminated precursors for degradable magneto- and thermo-sensitive polymer networks were prepared via two subsequent surface-initiated ring-opening polymerizations (ROPs) with ω-pentadecalactone and ε-caprolactone. A two-step mass loss obtained in thermogravimetric analysis and two distinct melting transitions around 50 and 85°C observed in differential scanning calorimetry experiments, which are attributed to the melting of OPDL and OCL crystallites, confirmed a successful preparation of the modified MNPs. The oligomeric coating of the nanoparticles could be visualized by transmission electron microscopy. The investigation of degrafted oligomeric coatings by gel permeation chromatography and 1H-NMR spectroscopy showed an increase in number average molecular weight as well as the presence of signals related to both of oligo(ω-pentadecalactone) (OPDL) and oligo(ε-caprolactone) (OCL) after the second ROP. A more detailed analysis of the NMR results revealed that only a few ω-pentadecalactone repeating units are present in the degrafted oligomeric bi-layers, whereby a considerable degree of transesterification could be observed when OPDL was polymerized in the 2nd ROP step. These findings are supported by a low degree of crystallinity for OPDL in the degrafted oligomeric bi-layers obtained in wide angle X-ray scattering experiments. Based on these findings it can be concluded that Sn(Oct)2 was suitable as catalyst for the preparation of nanosized bi-layered coated MNP precursors by a two-step ROP.

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Preparation and Characterization of a Novel Flame Retardant

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.47-50.294 ◽

2008 ◽

Vol 47-50 ◽

pp. 294-297 ◽

Cited By ~ 1

Author(s):

Xiu Wei Jia ◽

Min Zhi Rong ◽

Ming Qiu Zhang

Keyword(s):

Flame Retardant ◽

Sol Gel ◽

Average Molecular Weight ◽

Regular Structure ◽

Gel Permeation Chromatography ◽

Helical Conformation ◽

Infrared Spectrometry ◽

Resonance Spectroscopy ◽

X Ray Diffraction

A novel flame retardant polymethylsilsesquioxane (PMSQ) was successfully obtained via combination of non-hydrolytic and hydrolytic sol-gel routes. Chemical structure of the resultant PMSQ was determined by nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectrometry and powder X-ray diffraction, respectively. All the measurements demonstrated that the product possessed regular structure with chain-to-chain width of 0.87nm and chain thickness of 0.40nm. Weight average molecular weight of PMSQ was measured to be 3.5×105 using gel permeation chromatography. Numerical simulations of the molecular structure suggested that PMSQ should exhibit cis-isotactic configuration and double helical conformation at undisturbed condition.

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Kinetic Studies on the Curing Reactions of Fluoroepoxy Oligomer and Cycloaliphatic Amine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.747.753 ◽

2013 ◽

Vol 747 ◽

pp. 753-756 ◽

Cited By ~ 1

Author(s):

Thitinun Chongtum ◽

Wunpen Chonkaew

Keyword(s):

Average Molecular Weight ◽

Gel Permeation Chromatography ◽

Kinetic Studies ◽

Equivalent Weight ◽

Number Average Molecular Weight ◽

Polymeric Systems ◽

Acid Titration ◽

Curing Kinetic ◽

Gel Permeation

The curing kinetic analysis is an important technique for the characterization of the curing behavior of reactive polymeric systems. In this study, fluoroepoxy oligomer was synthesized from trifluoromethyl aniline and epichlorohydrin. The epoxide equivalent weight (EEW) and the number average molecular weight (Mn) of the systhesized fluroepoxy oligomer determined from acid titration and gel permeation chromatography were found to be 312.16 g/eq and 534 g/mol, respectively. The mixtures of the fluoroepoxy oligomer were mixed with the cycloaliphatic amine in various stiochiometric ratios (1:1, 1: 1.5 and 1:2). The effects of the stiochiometric ratio on the curing behaviors were studied using both isothermal and non-isothermal DSC methods. Ozawas, Kissingers and Friedmans methods were employed to investigate the kinetic parameters. The results showed that the peak temperature (Tp) increased with the increasing heating rate. The activation energy (Ea) calculated from Ozawas and Kissingers methods were much larger than that from Friedmans method.

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Study on Synthesis of Cyclotriphosphazene Containing Aminopropylsilicone Functional Group as Flame Retardant

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.683.25 ◽

2013 ◽

Vol 683 ◽

pp. 25-29 ◽

Cited By ~ 3

Author(s):

Lan Lan He ◽

Yi Zhang ◽

Zhao Lu Qin ◽

Yan Hua Lan ◽

Ding Hua Li ◽

...

Keyword(s):

Flame Retardant ◽

Chemical Structure ◽

Gel Permeation Chromatography ◽

Molar Ratio ◽

Reaction Conditions ◽

Element Analysis ◽

Fourier Transformed Infrared Spectroscopy ◽

Industrial Grade ◽

Distribution Calculation ◽

Optimum Reaction

A novel non-halogen flame retardant APESP, cyclotriphosphazene containing six aminopropyltriethoxysilicone functional groups N3P3[NH(CH2)3Si(OCH2CH3)3]6, was synthesized by menas of SN2 nucleophilic substitution reaction, using hexachlorocyclotriphosphazene(HCCP) and 3-aminopropyltriethoxy-silane (KH550) as material. Firstly the industrial grade HCCP was purified through recrystallization and sublimation. Then the reaction process was investigated to prompt the yield, and the optimum reaction conditions were as follows: triethylamine as acid-binding agent, tetrahydrofuran as solvent, HCCP/KH550/triethylamine molar ratio 1:7.2:7.2, dripping time: 1 hour, temperature: 67°C and reaction time: 20h. Maximum APESP yield reached 94.3%. The chemical structure and purity was characterized by element analysis, Fourier-transformed infrared spectroscopy (FTIR), mass spectrum, gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) analysis. The results showed that the structure of synthesized product is consistent with the theoretical structure, in which the chlorine atoms were completely substituted. The charge distribution calculation of HCCP and KH550 confirmed the reaction mechanism.

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Purification, Characterization, Prebiotic Preparations and Antioxidant Activity of Oligosaccharides from Mulberries

Molecules ◽

10.3390/molecules24122329 ◽

2019 ◽

Vol 24 (12) ◽

pp. 2329 ◽

Cited By ~ 6

Author(s):

Erna Li ◽

Shiyuan Yang ◽

Yuxiao Zou ◽

Weiwei Cheng ◽

Bing Li ◽

...

Keyword(s):

Antioxidant Activities ◽

Radical Scavenging Activity ◽

Average Molecular Weight ◽

Radical Scavenging ◽

Lactobacillus Rhamnosus ◽

Gel Permeation Chromatography ◽

Water Soluble ◽

Gas Chromatography Mass Spectrometry ◽

Trolox Equivalent Antioxidant Capacity ◽

Antioxidant Power

A water-soluble oligosaccharide termed EMOS-1a was prepared by enzymatic hydrolysis of polysaccharides purified from mulberries by column chromatography. The chemical structure of the purified fraction was investigated by ultraviolet spectroscopy, Fourier-transform infrared spectroscopy, and gas chromatography–mass spectrometry, which indicated that galactose was the main constituent of EMOS-1a. Chemical analyses showed that the uronic acid and sulfate content of EMOS-1a were 5.6% and 8.35%, respectively, while gel permeation chromatography showed that EMOS-1a had an average molecular weight of 987 Da. The antioxidant activities of EMOS-1a were next investigated, and EMOS-1a exhibited concentration-dependent 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, Trolox equivalent antioxidant capacity, and ferric reducing antioxidant power. The level of proliferation of Lactobacillus rhamnosus reached 1420 ± 16% when 4% (w/v) EMOS-1a was added, where the number of colonies in MRS (de Man, Rogosa, and Sharpe) medium with no added oligosaccharide was defined as 100% proliferation. These results indicate that the oligosaccharide EMOS-1a could be used as a natural antioxidant in prebiotic preparations.

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Energy Recovery from Waste Tires Using Pyrolysis: Palestine as Case of Study

Energies ◽

10.3390/en13071817 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1817 ◽

Cited By ~ 2

Author(s):

Ramez Abdallah ◽

Adel Juaidi ◽

Mahmoud Assad ◽

Tareq Salameh ◽

Francisco Manzano-Agugliaro

Keyword(s):

Carbon Black ◽

West Bank ◽

The Other ◽

Liquid Fuels ◽

Pyrolysis Oil ◽

Pyrolysis Gas ◽

Heating Value ◽

Waste Tires ◽

High Heating Value ◽

High Heating

The first industrial-scale pyrolysis plant for solid tire wastes has been installed in Jenin, northern of the West Bank in Palestine, to dispose of the enormous solid tire wastes in the north of West Bank. The disposable process is an environmentally friendly process and it converts tires into useful products, which could reduce the fuel crisis in Palestine. The gravimetric analysis of tire waste pyrolysis products from the pyrolysis plant working at the optimum conditions is: tire pyrolysis oil (TPO): 45%, pyrolysis carbon black (PCB): 35%, pyrolysis gas (Pyro-Gas): 10% and steel wire: 10%. These results are depending on the tire type and size. It has been found that the produced pyrolysis oil has a High Heating Value (HHV), with a range of 42 − 43 ( MJ / kg ) , which could make it useful as a replacement for conventional liquid fuels. The main disadvantage of using the TPO as fuel is its strong acrid smell and its low flash point, as compared with the other conventional liquid fuels. The produced pyrolysis carbon black also has a High Heating Value (HHV) of about 29 (MJ/kg), which could also encourage its usage as a solid fuel. Carbon black could also be used as activated carbon, printers’ ink, etc. The pyrolysis gas (Pyro-Gas) obtained from waste tires mainly consist of light hydrocarbons. The concentration of H2 has a range of 30% to 40% in volume and it has a high calorific value (approximately 31 MJ / m 3 ), which can meet the process requirement of energy. On the other hand, it is necessary to clean gas before the burning process to remove H2S from Pyro-Gas, and hence, reduce the acid rain problem. However, for the current plant, some recommendations should be followed for more comfortable operation and safer environment work conditions.

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