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1.
The storage and thermal stability of blends of the ether‐soluble fraction of bio‐oil (ES) and bio‐diesel are reported. Fuel properties such as viscosity, water content, acid number and average molecular weight of the ES/bio‐diesel blends were measured before and after aging. Compared to the aging properties of bio‐oil alone, very small changes in water content and viscosity were shown for the blends aged at 80 °C for 180 h. Chemical changes were characterized using gel permeation chromatography, showing a slight increase in the molecular weight over time. Further confirmation of the changes was provided through Fourier transform infrared spectrometry, thermal decomposition analysis using a thermogravimetric analyzer, proton assignment using proton nuclear magnetic resonance, and carbon assignment using carbon nuclear magnetic resonance. Overall, the study indicates that ES/bio‐diesel blends are stable as fuel under the conditions tested in this paper.  相似文献   

2.
A method of ultrasound‐assisted reduction of a nickel‐ammonia complex with borohydride in aqueous solution was used to prepare NiMoB/MCM‐41 and NiMoB/SBA‐15 supported amorphous alloy catalysts. These catalysts were used to upgrade bio‐oil at mild temperatures ranging from 100 to 160 °C and recycling of these two supported catalysts and of unsupported NiMoB was carried out. Then, fresh and third time used catalysts were characterized by X‐ray diffraction, X‐ray photoelectron spectra, and transmission electron microscopy. Quantitative results were obtained from the analysis of gas chromatography/mass spectrometry. Through mild upgrading, 1‐hydroxy‐2‐propanone, furfural, and 2‐methoxy‐4‐vinylphenol in the bio‐oil were converted to relevant alcohols and saturated phenols. The conversion rates were 45.7, 71.5, and 57.1 %, respectively, when crude bio‐oil was upgraded using NiMoB/MCM‐41 at 160 °C. The two supported catalysts, especially NiMoB/MCM‐41, had smaller amorphous NiMoB particles and exhibited more uniform dispersion on mesoporous silica, leading to higher reaction activity and stability than unsupported NiMoB. Deactivation of these catalysts resulted from the reduction of Ni0, B0, and Mo4+ species on the surface, the transition from the amorphous to the crystalline state, particle agglomeration, and coke deposition on the surface.  相似文献   

3.
Q. Xu  Z. Zhang  Y. Yan 《化学工程与技术》2013,36(12):2163-2168
A novel method of bio‐oil upgrading over Ni‐based catalysts under CO atmosphere and optimum conditions for a Ni/Cu/Zn/Al catalyst were determined. The oxygen content as well as the water content decreased significantly and the pH value of upgraded bio‐oil was higher than that of crude bio‐oil. The physical properties indicate that upgraded bio‐oil was more stable than crude bio‐oil.  相似文献   

4.
Various Ni‐Co bimetallic catalysts were prepared by incorporating sol‐gel and wet impregnation methods. A laboratory‐scale fixed‐bed reactor was employed to investigate their effects on hydrogen production from steam reforming of bio‐oil. The catalyst causes the condensation reaction of bio‐oil, which generates coke and inhibits the formation of gas at temperatures of 250 °C and 350 °C. At 450 °C and above the transformation of bio‐oil is initiated and gaseous products are generated. The catalyst also can promote the generation of H2 as well as the transformation of CO and CH4 and plays an active role in steam reforming of bio‐oil or gaseous products from bio‐oil pyrolysis. The developed 3Ni9Co/Ce‐Zr‐O catalyst achieved maximum hydrogen yield and lowest coke formation rate and provided a better stability than a commercial Ni‐based catalyst.  相似文献   

5.
Utilization of bionics to develop stimuli responsive polymers that can heal damage with excellent restorability is particularly attractive for a sustainable society. Herein, inspired by chameleons, a hierarchical structural design strategy is proposed and illustrated to fabricate a healable photochromic material based on a self‐healable polymeric matrix and a finely dispersed photochromic spirooxazine. The self‐healable polymeric matrix is fabricated via the integration of multiple hydrogen bonds (H bonds) and covalent cross‐links into a biomass‐derived elastomer. The dynamic nature and soft characteristics enable the as‐prepared elastomer superior extensibility as well as self‐healing ability, while the covalent cross‐links can assist the reassociation of ruptured H bonds. The representative elastomer exhibits an extensibility of 2600% and toughness of 42.76 MJ m?3. Furthermore, it shows good self‐healing ability with complete recovery of scratch as well as restoration against 1900% of elongation and 24.1 MJ m?3 of toughness after healing at 60 °C for 24 h. This combination of moderate toughness, good self‐healing ability, and smart photochromic property in biomass‐derived materials should largely improve their applicability, reliability, and sustainability in various materials and devices.  相似文献   

6.
Pyrolytic lignin is attributed to the instability of bio‐oil but is a potential chemical material. To improve the stability and increase the economic viability of bio‐oil, high‐ and low‐molecular‐mass pyrolytic lignin (HMM and LMM) were obtained using solvent extraction. The microstructure of pyrolytic lignin was examined by Fourier transform infrared spectrometry (FTIR). The dissimilar absorption intensities indicated the different content of corresponding functional groups in HMM and LMM. The pyrolysis behavior of HMM and LMM was studied by thermogravimetry coupled with FTIR. Obviously pyrolytic lignin undergoes three weight loss stages.  相似文献   

7.
A final optimal mixed additive consisting of methanol, acetone, and ethyl acetate in specific proportions was obtained by one‐factor multi‐objective optimization of the Design‐Expert software and performed well in a verification experiment. The mixed additive of methanol and ethyl acetate was first prepared separately and then added to bio‐oil, followed by acetone. The viscosity of the additive/bio‐oil mixture was significantly lower than of the crude bio‐oil. Among all chemical compound groups in the bio‐oil, the content of phenols was the highest one. Chemical compounds in bio‐oil after aging had higher molecular mass weights than before. The addition of the final optimal mixed additive and the accelerated aging process could slightly change the intensity and positions of some absorption peaks.  相似文献   

8.
Two model bio‐oil fractions were chosen as two different major classes of components present in bio‐oil. Steam reforming of the two fractions was carried out to investigate the gas product distributions and carbon deposition behavior. Higher H2 yield and carbon conversion to the gaseous phase can be obtained at relatively low temperature (650 °C) for steam reforming of the light fraction. For steam reforming of the heavy fraction, a higher temperature (800 °C) is necessary to obtain higher H2 yield and carbon conversion to the gaseous phase. At 800 °C, the heavy fraction requires a higher steam to carbon ratio (10) than that for the light fraction (7) to achieve efficient steam reforming. Based on the same carbon space velocity, for 10 h stream time, the drop of H2 yield and carbon conversion to the gaseous phase in the steam reforming of the heavy fraction is more rapid than that of the light fraction. Carbon deposition in the steam reforming of the heavy fraction is much more severe than that of the light fraction, as determined by carbon content analysis and SEM detection.  相似文献   

9.
De‐inking sludge, an ash‐rich recycling paper solid waste, is generated in huge amounts. The catalytic deoxygenation potential of calcium‐based de‐inking sludge in co‐pyrolysis mode with wood and its neat thermal conversion to sustainable biofuels are investigated. Wood, de‐inking sludge, and their blends are processed in a thermocatalytic reforming (TCR) system. In the presence of de‐inking sludge, the oxygen content in the organic phase decreases and the bio‐oil calorific value improves as compared to the neat wood‐derived bio‐oil. The TCR processing of neat de‐inking sludge produces a bio‐oil with low oxygen content and higher calorific value.  相似文献   

10.
Oil palm trunk is a major lignocellulosic-rich, solid waste material generated from palm-oil upstream industry. The activated carbons prepared from oil palm trunk pretreated with phosphoric acid with the ratio of the acid to the precursor of 0.9, followed by carbonization and activation by carbon dioxide resulted in a high surface area of more than 1800 m2/g with 90% content of micropore surface area. The surface area and the nature of the porosity of the resulting activated carbons were found to be dependent on the amount of the activator used for a fixed quantity of the precursor. Pretreatment of the precursor at low ratio of the phosphoric acid has added advantage, due to the tremendous increase in the apparent surface area of the resulting activated carbon and at the same time enriching its micropore nature. This could result in the conservation of the micropore fraction. On the other hand, using too high a ratio of the phosphoric acid to the precursor did not increase the apparent surface area very much, but instead destroyed the micropore component, and thus increasing the mesopore fraction of the resulting activated carbon. This study also shows that oil palm trunk, a by-product of oil palm industry has a great potential as a raw material for activated carbon production.  相似文献   

11.
P. Lan  Q. Xu  M. Zhou  L. Lan  S. Zhang  Y. Yan 《化学工程与技术》2010,33(12):2021-2028
Catalytic steam reforming of bio‐oil is an economically‐feasible route which produces renewable hydrogen. The Ni/MgO‐La2O3‐Al2O3 catalyst was prepared with Ni as active agent, Al2O3 as support, and MgO and La2O3 as promoters. The experiments were conducted in fixed bed and fluidized bed reactors, respectively. Temperature, steam‐to‐carbon mole ratio (S/C), and liquid hourly space velocity (LHSV) were investigated with hydrogen yield as index. For the fluidized bed reactor, maximum hydrogen yield was obtained under temperatures 700–800 °C, S/C 15–20, LHSV 0.5–1.0 h–1, and the maximum H2 yield was 75.88 %. The carbon deposition content obtained from the fluidized bed was lower than that from the fixed bed. The maximum H2 yield obtained in the fluidized bed was 7 % higher than that of the fixed bed. The carbon deposition contents obtained from the fluidized bed was lower than that of the fixed bed at the same reaction temperature.  相似文献   

12.
应用现有装置,把未洗三混直接作为工业萘原料。  相似文献   

13.
F. Huang  W. Li  Q. Lu  X. Zhu 《化学工程与技术》2010,33(12):2082-2088
A homogeneous RuCl2(PPh3)3 catalyst was prepared for the hydrogenation of bio‐oil to improve its stability and fuel quality. Experiments were first performed on three model aldehydes of acetaldehyde, furfural and vanillin selected to represent the linear aldehydes, oxygen heterocyclic aldehydes and aromatic aldehydes in bio‐oil. The results demonstrated the high hydrogenation capability of this homogeneous catalyst under mild conditions (55–90 °C, 1.3–3.3 MPa). The highest conversion of the three model aldehydes was over 90 %. Furfural and acetaldehyde were singly converted to furfuryl alcohol and ethanol after hydrogenation, while vanillin was mainly converted to vanillin alcohol, together with a small amount of 2‐methoxy‐4‐methylphenol and 2‐methoxyphenol. Further experiments were conducted on a bio‐oil fraction extracted by ethyl acetate and on the whole bio‐oil at 70 °C and 3.3 MPa. Most of the aldehydes were transformed to the corresponding alcohols, and some ketones and compounds with C–C double bond were converted to more stable compounds.  相似文献   

14.
The average molecular formula of asphaltene was calculated from the main functional groups of asphaltene determined by Fourier transform infrared spectroscopy, the average molecular weight found by gel filtration chromatography, and values of ultimate analysis. A series of average structure parameters were determined by 1H NMR and 13C NMR spectrum integrals, followed by establishing the structure models of asphaltene according to the Brown‐Ladner method. Reduction of molecular weight of asphaltene was observed after bio‐oil upgrading, and the oxygen‐containing functional groups were apparently less than that of crude bio‐oil while the number of aromatic rings was increased. The upgraded bio‐oil had a lower molecular weight, lower oxygen content, and higher aromaticity compared with crude bio‐oil.  相似文献   

15.
通过对页岩油氧化、络合,脱出原料油中的碱氮成分和降低总氮含量,从而满足页岩油进行催化裂化的进料要求。经过TYPEZD-2自动电位滴定仪和REN-1000B化学发光定氮仪对单因素试验与正交试验的检测,确定了在反应温度70℃、反应时间20min、m(氧化剂)/m(油)为0.068∶1的条件下,通过简单的试验方法和少量的试剂能够将页岩油中氮含量降低到3925.29μg/g,能够达到催化裂化进料标准,但预处理后原料油的损失尚未达到理想状态。  相似文献   

16.
Bio‐based rubbers prepared by tandem cationic polymerization and ROMP using a norbornenyl‐modified linseed oil, Dilulin?, and a norbornene diester, NBDC, have been prepared and characterized. Increasing the concentration of the NBDC in the mixture results in a decrease in the glass transition temperature. The new bio‐based rubbers exhibit tensile test behavior ranging from relatively brittle (18% elongation) to moderately flexible (52% elongation) and with decreasing values of tensile stress with increasing NBDC content. Thermogravimetric analysis reveals that the bio‐based rubbers have maximum decomposition temperatures of over 450 °C with their thermal stability decreasing with increasing loadings of NBDC.

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17.
The direct conversion of waste cooking oil (WCO) into bio‐jet fuel was investigated over a core‐shell hierarchical USY@Al‐SBA‐15 zeolite‐supported NiMo catalyst. The core‐shell structure showed better acid and pore size distributions. The synergetic effect of the core‐shell micropore and mesopore structure significantly contributed to enhancing the selectivity for the jet fuel (C9–15 hydrocarbons) from 9.3 % over NiMo/USY up to 35.7 % over NiMo/USY@Al‐SBA‐15, with high isomerization (iso‐/n‐paraffins ratio = 2.7) and moderate aromatic fraction (18.7 %). The decarboxylation reaction was selectively enhanced. Optimal selectivity for jet fuel (39.7 %) was obtained at 380 °C and a high H2/oil ratio would decrease the yield of jet fuel. This catalyst showed excellent stability for the hydroconversion of WCO to hydrocarbons.  相似文献   

18.
19.
A new method for the synthesis of high‐molar‐mass (MM), bio‐based polyols for elastic polyurethanes is developed. This process is based on the self‐condensation of low MM polyols (Mn ≈ 1000) and vacuum removal of the resulting glycerol. Self‐condensation products are hyperbranched estolide polyols with average MMs close to 3000 and hydroxyl numbers in the range of 40–95 mg KOH g?1. Three polyols, one with primary and two with secondary hydroxyls and different functionalities, are studied. The transesterification proceeded much faster with primary hydroxyls, leading to high‐viscosity products. The effect of functionality and reactivity of starting polyols on properties is discussed. Practical applications: The process is useful for upgrading the existing natural oil‐based polyols to higher MM, lower OH number and variable‐functionality polyols, for expanding application in the urethane field. The process is simple, involving just an oil‐based polyol, a catalyst, and heating under vacuum.  相似文献   

20.
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