改性SBA-15催化剂用于棕榈酸甲酯脱氧提质

以水热稳定性高的Al-SBA-15介孔分子筛为载体,负载CuO制备了CuO/Al-SBA-15催化剂,并采用一步合成法制备出Fe-Al-SBA-15催化剂,对其进行了XRD、TEM及FTIR等测试及表征。以Al-SBA-15、CuO/Al-SBA-15及Fe-Al-SBA-15为催化剂,进行棕榈酸甲酯的非临氢脱氧反应。结果表明：CuO在介孔材料表面均匀分散,三种催化剂中CuO/Al-SBA-15的脱氧效果最好,确定最佳反应条件为反应温度342 ℃,反应时间2 h。与未加催化剂相比,在最佳反应条件下,棕榈酸甲酯脱羧产生烃类的选择性提高了40~60 %。催化剂重复使用3次,棕榈酸甲酯的转化率无明显下降。根据活性评价推测脱羧反应机理为：在亚临界水中棕榈酸甲酯水解生成棕榈酸,在催化剂的活性中心上羧酸根负离子形成羧基化物,之后被活化氢进攻临近羧基的C-C键,进而CO2脱附下来,生成主产物十五烷。     

改性SBA-15催化剂用于棕榈酸甲酯脱氧提质

以水热稳定性高的Al-SBA-15介孔分子筛为载体,负载CuO制备了CuO/Al-SBA-15催化剂,并采用一步合成法制备出Fe-Al-SBA-15催化剂,对其进行了XRD、TEM及FTIR测试及表征。分别以Al-SBA-15、CuO/Al-SBA-15及Fe-Al-SBA-15为催化剂,进行了棕榈酸甲酯的非加氢脱氧反应。结果表明:CuO在介孔材料表面均匀分散,3种催化剂中CuO/Al-SBA-15的脱氧效果最好,确定最佳反应条件为反应温度342℃,反应时间2 h。与未加催化剂相比,在最佳反应条件下,棕榈酸甲酯脱羧产生烃类的选择性提高了40%~60%。催化剂重复使用3次,棕榈酸甲酯的转化率无明显下降。根据活性评价推测脱羧反应机理为:在亚临界水中棕榈酸甲酯水解生成棕榈酸,在催化剂的活性中心上羧酸根负离子形成羧基化物,之后被活化氢进攻邻近羧基的C—C键,进而CO2脱附下来,生成主产物十五烷。     

Biomass to hydrogen via catalytic steam reforming of bio-oil over Ni-supported alumina catalysts

Production of hydrogen (H₂) from catalytic steam reforming of bio-oil was investigated in a fixed bed tubular flow reactor over nickel/alumina (Ni/Al₂O₃) supported catalysts at different conditions. The features of the steam reforming of bio-oil, including the effects of metal content, reaction temperature, W_bHSV (defined as the mass flow rate of bio-oil per mass of catalyst) and S/C ratio (the molar ratio of steam to carbon fed) on the hydrogen yield were investigated. Carbon conversion (moles of carbon in the outlet gases to moles of the carbon feed) was also studied, and the outlet gas distributions were obtained. It was revealed that the Al₂O₃ with 14.1% Ni content gave the highest yield of hydrogen (73%) among the catalysts tested, and the best carbon conversion was 79% under the steam reforming conditions of S/C = 5, W_bHSV = 13 1/h and temperature = 950 °C. The H₂ yield increased with increasing temperature and decreasing W_bHSV; whereas the effect of the S/C ratio was less pronounced. In the S/C ratio range of 1 to 2, the hydrogen yield was slightly increased, but when the S/C ratio was increased further, it did not have an effect on the H₂ production yield.     

CaO表面更新对微拟球藻催化热解制备生物油的影响

分别以水合化法和热缺陷法对CaO进行表面更新,用N₂物理吸附(BET)、X射线衍射(XRD)、扫描电镜(SEM)和CO₂吸附技术对表面更新后的CaO进行了结构表征,并利用制备的CaO在管式炉内对微拟球藻进行了催化热解研究.结果表明:两种更新方法均能明显提高CaO的比表面积、介孔数目及孔体积.CaO的表面更新处理没有改变基本的晶相结构,仍为立方晶型.两种更新方法均能显著提高CaO的催化活性,且改善了产物油品的性能.相比较而言,水合CaO的催化脱氧性能较高,催化热解得到的生物油产率为28.65%、含氧量为4.67%、热值高达38.600 kJ·g^-1、运动黏度低(8.011 mm²·s^-1)、含水率低(2.49%),且催化热解后的生物油以C₁₂～C₁₇饱和直链烷烃为主,适合进一步精制为生物柴油.     

Catalytic decarboxylation of fatty acids to hydrocarbons over non-noble metal catalysts: the state of the art

The catalytic decarboxylation of fatty acids to yield hydrocarbons, for use as biofuel as a main target, is a topical reaction in which the main challenge is actually to control the selectivity while using the smallest amount of hydrogen possible (or even better, not using hydrogen at all) in order to optimize cost-efficiency of the process. Herein, the focus is on the non-noble mono-, bi- and tri-metallic catalysts used to carry out this reaction. Historically, several non-noble monometallic catalysts based on Cu, Co, Ni supported on different types of supports were first studied. Among such materials, the Co-based catalysts were not selective, while, Cu-based catalysts were more or less selective to hydrocarbons or to olefins, depending on the support used. Among these three metals, the Ni-based catalysts are the most widely described ones due to their specific ability to promote deoxygenation reactions. Combining Ni to a second metal yielded a synergistic effect toward better catalytic performances, with increases in both conversion and selectivity and also improvement of the resistance of the catalyst to carbon deposit, especially when adding non-noble metals. For future prospects, it appears that the main challenge will be to be able to maintain good catalytic performances under inert gas in solvent-free conditions, in order to yield a fully environmentally friendly and cost-effective process. © 2018 Society of Chemical Industry     

生物油对生物油基淀粉胶黏剂性能的影响

我国的生物质资源丰富,将其快速热解成生物油,作为优质化工原料应用,可实现其高值高效应用。本文对以生物油制备的环境友好型生物油淀粉胶黏剂基本性能进行研究,结果表明,其湿胶合强度可达到国标Ⅱ类胶合板标准,其黏度可以满足胶合板工业化生产需求;生物油淀粉胶黏剂流变行为呈现出明显的剪切变稀特征,是典型的假塑性流体,流动活化能△E_η为9.67 kJ·mol^-1,表明其具有良好的流动性和应用潜力;通过对比不同生物油加入量的BOS胶黏剂湿胶合强度、流变性和热稳定性的研究发现,生物油的加入可改善BOS胶黏剂的耐水性,促进其固化,并增强其热稳定性。     

脱碱赤泥催化剂制备及对秸秆催化热解生物油成分的影响

赤泥含有具有催化作用的元素,同时含有一定的孔,可用作催化剂。赤泥的强碱性导致催化剂表面烧结、酸性不足等问题。该研究采用柠檬酸交换钠及焙烧制备了脱碱赤泥催化剂,赤泥的脱碱率达到96%。表征发现脱碱赤泥结构更稳定,硅铝酸盐聚合度降低,Al、Fe、Ti等具有催化作用的元素含量增加、比表面积增加、中强酸酸性位点增多等。用于催化秸秆热解,产物生物油中醛类、酚类、呋喃类变化明显,其中2,3-二氢呋喃含量增加了15.9倍。脱碱赤泥对生物油的产率影响较小,不可冷凝气体、生物炭产率变化明显。推断与脱碱赤泥促进了脱羟和脱羰基反应、葡萄糖脱水重排,强化了脱甲基和脱甲氧基反应有关。     

Bio-coke from upgrading of pyrolysis bio-oil for co-firing

Bio-cokes were formed by upgrading pyrolysis oils from wheat spent grain and rapeseed meal biomasses using a thermo-t vis-breaking technology. The bio-cokes presented moisture levels below 2 wt.%, were virtually ash-free and had very low oxygen contents in the range of 10–14 wt.%. Their calorific values were in the range of 29–37 MJ/kg comparable to that of bituminous coal. About 15–25 wt.% of the original biomass on dry ash-free basis was converted into the ash-free bio-coke and about 20–40% of the heating value of the original biomass was retained in the bio-coke. From TGA analysis it was found that the fuel properties of the bio-coke from wheat spent grain were comparable to those of coal, where blends of up to 50 wt.% of WSG bio-coke with coal showed virtually similar oxidation behaviour to that of coal. This work shows that low-density biomass can be transformed into high density bio-coke that can logistically be treated like coal and indicates that co-firing with bio-coke can easily exceed current levels in the future.     

生物油储存稳定性的研究进展

保持良好的储存稳定性是生物油作为替代能源进入市场应用的关键之一。本文介绍了生物油的基本特性、储存稳定性的研究现状以及测量评价生物油储存稳定性的参数和方法,并重点介绍了目前提高生物油储存稳定性的方法,分析了不同方法的优缺点以及目前所面临的问题,并提出了深入生物质快速热解机理并制定关于生物油储存稳定性及应用的标准将有助于生物油的市场商业应用。     

The effects of mineral salt catalysts on selectivity of phenolic compounds in bio-oil during microwave pyrolysis of peanut shell

Catalytic microwave pyrolysis of peanut shell (PT) using Fe₃O₄, Na₂CO₃, NaOH, and KOH for production of phenolic-rich bio-oil was investigated. The effects of catalyst type, pyrolysis temperature, and biomass/catalyst ratio on product distribution and composition were studied. Among four catalysts tested, Na₂CO₃ significantly increased the selectivity of phenolic compounds in bio-oil during microwave pyrolysis. The highest phenolics concentration of 57.36% (area) was obtained at 500 °C and PT:Na₂CO₃ ratio of 8: 1. The catalytic effect to produce phenolic compounds among all the catalysts tested can be summarized in the order Na₂CO₃>Fe₃O₄>KOH>NaOH. Using KOH and NaOH as catalyst resulted in formation of bio-oil with enhanced higher heating value (HHV) and lower oxygen content, indicating that these catalysts enhanced the deoxygenation of bio-oil. The scanning-electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) analysis of char particles showed the melting of magnetite and vaporizationcondensation of mineral salt catalysts on char particle, which was attributed to extremely high local temperatures during microwave heating.     

厨余垃圾水热液化制取生物燃料

以厨余垃圾为原料进行水热液化,考察了反应温度和料液比对产物分布的影响。温度320℃、料液比1:15时,生物油产率最高为16.7%,继续升高温度或降低料液比将促进气体产物生成。与重质原油、常减压渣油相比,生物油氧、氮元素含量较高,热值为32.33~34.82 MJ·kg^-1,其中汽油和煤柴油馏分超过50%。利用GC-MS、FT-IR和FT-ICR MS对生物油化学组成、官能团和杂原子组成进行了表征。生物油是一种复杂混合物体系,已检测出烃类、酸类、醛类、酮类、酯类、胺类、酚类、醇类和含氮杂环类等多种物质,对其酸性组分进一步分析显示,含氧组分主要是O₂、O₃类化合物,含氮组分主要是N₁O₂、N₁O₃和N₁O₄类化合物。     

Production of aromatic hydrocarbons by co-cracking of bio-oil and ethanol over Ga2O3/HZSM-5 catalysts

The catalytic cracking of bio-oil is important to produce aromatic hydrocarbons, which can partially replace gasoline or diesel to greatly reduce carbon emissions from transportation. To further promote the formation of aromatic hydrocarbons, this work studied the effects of the preparation method and the acid strength of Ga₂O₃/HZSM-5 on catalytic cracking of the bio-oil distilled fraction systematically. The preparation method of Ga₂O₃/HZSM-5 had an important effect on its catalytic activity: the Ga₂O₃/HZSM-5 prepared by physical mixing showed the low dispersion of active phases and poor pore structure, resulting in its insufficient activity and severe coke deposition; the Ga₂O₃/HZSM-5 prepared by precipitation exhibited the higher activity, while many polycyclic aromatic hydrocarbons unfavorable for the subsequent utilization were in the oil phase; the Ga₂O₃/HZSM-5 prepared by impregnation showed the highest activity and 35.5% (mass) selectivity of the oil phase, including 80.3% monocyclic aromatic hydrocarbons and 12.0% polycyclic aromatic hydrocarbons. The Brønsted acidity of Ga₂O₃/HZSM-5 decreased with Si/Al ratio, leading to the decline in reactant conversion, oil phase selectivity and quality. Meanwhile, the polymerization between monocyclic aromatic hydrocarbons and oxygenates was promoted to produce many polycyclic aromatic hydrocarbons and even coke, causing catalyst deactivation.     

提高生物油稳定性的方法

稳定性对生物油的应用十分重要。介绍了导致生物油不稳定的机理和各种提高生物油稳定性的方法,如原料干燥、酸（水）洗脱灰、气体高温过滤、气相催化裂解、添加溶剂和生物油适度加氢等。从这些方法中选择合适的提高生物油稳定性的方案需要从生物油的初始性质、应用范围和处理成本等方面进行综合考虑。     

Recent advances in the catalytic hydrodeoxygenation of bio-oil

Owing to the increasing interest in alternative energy, there is a focus on bio-oil production from biomass because it is an abundant and renewable energy source. Among the various kinds of biomass conversion technologies, pyrolysis has been investigated widely to produce bio-oil. However, the direct use of bio-oil is difficult because of its poor quality due to the large amounts of oxygen-containing compounds, such as acids, ketones, and esters. Therefore, an additional suitable upgrading process for bio-oil is required. Hydrodeoxygenation (HDO) is considered effective for the deoxygenation of bio-oil. This paper reviews the recent progress in the catalytic HDO of bio-oil. In addition, the effects of the solvent and catalyst applied to the HDO of bio-oil are reviewed intensively together with a discussion of the deactivation behavior of the catalyst during HDO.     

An in situ reduction approach for bio-oil hydroprocessing

An in situ reduction treatment, combination of reduction and esterification, was investigated to refine bio-oil. Over Raney Ni and zeolites-supported noble metal (Pd and Ru) catalysts, the reductant formic acid decomposed into hydrogen and carbon dioxide, and then hydrogen reduced the bio-oil while compressible CO₂ dissolved in methanol to form a CO₂-CH₃OH expanded liquid. The results showed that Raney Ni and zeolites-supported Ru were highly active in this heterogeneous catalytic system. The reactions preformed at 150-230 °C for 5-7 h would give a better upgraded bio-oil with a high yield of 80-90 wt.%. The unsaturated components in bio-oil were reduced substantially without obvious coke formation, and the oxygen content was lowered by ca. 5 wt.%. Organic acids were converted into esters through the esterification with methanol, and the properties of hydrogenated bio-oil were improved: the pH value increased from 2.17 to ca. 4.5; the higher heating value approached to 22 MJ/kg, and the viscosity decreased from 5.31 to ca. 4.0 mm²/s.     

Steam pyrolysis of an industrial waste for bio-oil production

Potato skin, a food industry waste, was pyrolysed under three different atmospheres namely static, nitrogen, and steam to produce bio-oil and its derivatives. The oil yield obtained at 550 °C was 24.77% in static atmosphere, whereas it reached to 27.11% in nitrogen atmosphere. Moreover, the use of steam caused a sharp increase of oil yields up to 41.09% with a steam velocity of 1.3 cm s^− 1. TG-DTA analyses were applied on the raw material to investigate the thermal degradation. Liquid products obtained under the most suitable conditions were characterized by elemental analyses, FT-IR and ¹H NMR. In addition, column chromatography was employed to separate the bio-oil into its derivatives. Asphaltene fraction of bio-oil is decreased under steam atmosphere. Gas chromatography was also used to investigate the C distributions. The characterization has shown that the bio-oil obtained under steam atmosphere was more beneficial than those obtained under both static and inert atmospheres. Further comparison of H/C ratios of pyrolysis oils with conventional fuels indicates that the H/C ratios of the oils obtained in this study lie between those of light and heavy petroleum products. It can be concluded that potato skin could be evaluated as a promising biomass candidate of bio-oil production.     

稻壳快速热解制取生物质油的试验研究

目前生物质快速热解高温热解气主要利用间壁式冷却器进行冷凝,容易造成冷却管道的结焦堵塞问题,本试验根据流化床稀相输送特点、生物质的热解特性以及生物质油的冷凝收集特点,设计了生物质快速热解反应装置,改进生物质物快速冷凝系统,以稻壳为原料进行快速热解制取生物质油的试验研究,分别考察单因素反应温度、流化气量以及进料速度对生物质油产率的影响。试验表明:稻壳热解气能够快速顺利地得到冷凝,反应系统能够连续顺利运行,随着反应温度、流化气量、进料速度的增大,生物质油的产率都呈现先增大后减小的趋势。另外对产出的生物质油用气质联用设备进行了成分分析,得出了生物质油的主要成分,其中酸类、酮类、脂类以及酚类的含量相对较高。     

Hydrocarbons for diesel fuel via decarboxylation of vegetable oils

Deoxygenation reaction of vegetable oils over a carbon-supported metal catalyst was studied as a suitable reaction for production of diesel-fuel-like hydrocarbons. Stearic acid, ethyl stearate, and tristearine have been used as model compounds. Catalytic treatment of all the three reactants resulted in production of n-heptadecane as the main product with high selectivity.     

生物油淀粉胶黏剂固化特性研究

生物基胶黏剂具有环境友好、可再生等特性,具有广阔的应用前景。对生物油淀粉胶黏剂进行差热分析,研究了其固化过程中的热行为、固化反应动力学和固化工艺,为高效地优化、预测和控制其胶接工艺条件提供基础数据支撑;对比采用复合固化剂与单一固化剂的胶黏剂热行为,发现复合固化反应热更大,固化特征温度更低,表明复合固化剂体系固化更充分;不同生物油加入量对胶黏剂的热行为研究表明,随生物油加入量增加,固化反应放热量增加,但固化特征温度逐渐降低,进一步表明生物油有促进胶黏剂固化的作用。     

生物油淀粉胶黏剂制备工艺研究

对快速热解制得的杨木生物油进行GC-MS分析,确定其含有多种对制备淀粉基胶黏剂有益的有机组分。以生物油质量分数、生物油加入后淀粉乳液pH、生物油与淀粉乳液的反应时间以及固化剂质量分数4个关键条件为实验因素,胶合强度为考核指标,采用正交试验法优选出制备生物油淀粉胶黏剂的最佳工艺条件为:生物油质量分数为20%,pH为7.5,反应时间为45 min,固化剂质量分数为18%。用该胶黏剂制备的胶合板的胶合强度达到GB/T 9846.3—2004标准中Ⅱ类胶合板要求。