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1.
生物质催化转化是制备高品质生物基航空燃料和解决能源危机的主要途径,本文从现有的生物基航空燃料的制备方法出发,从适应需求的原料和技术路线的角度,概述了油脂、木质纤维、糖类等不同的原料所需的技术路线和催化体系,以及加氢脱氧、费-托合成、羟醛缩合、烯烃齐聚等不同技术路线所用的催化剂,同时对反应条件以及反应机理进行优化和探索,并指明催化转化过程中存在成本高、工艺和转化机理复杂(高温和高压)、H2用量高、目标产物的选择性较差以及催化剂失活等问题。最后,针对各种原料、技术路线的优缺点以及面临的问题,提出了建议并展望其未来发展方向。  相似文献   

2.
介绍了近年来纤维素催化转化制取C5/C6烷烃的反应和催化体系的研究进展,主要论述了纤维素通过水解-加氢脱氧的一锅法过程和纤维素经C6平台化合物的加氢脱氧过程,对天然木质纤维原料、纤维素、葡萄糖及山梨醇转化为烷烃的反应路径及相应的催化剂进行了总结。反应路径主要有山梨醇、异山梨醇、HMF和己内酯反应路径,催化剂主要为金属-酸多功能催化剂,酸催化剂包括金属氧化物、分子筛、杂多酸、离子液态酸性溶剂及无机酸等;金属催化剂主要有Pd、Pt、Ru、Ir、Ni等。其中金属Ru在酸性水热环境中具有良好的催化活性,研究最为广泛。通过分析各种反应途径及相应的催化剂,提出了该研究领域面临的主要问题,并从技术角度对未来应用前景进行了展望。  相似文献   

3.
催化加氢脱氧是实现木质素提质的重要方式.笔者采用流动电催化技术对木质素模型化合物进行加氢脱氧研究.以磷酸为阳极电解液,铂片电极为阳极电极,杂多酸磷钨酸为阴极电解液,石墨棒电极为阴极电极,构建炭载催化剂直接分布在阴极电解液中的流动电催化体系.考察了不同炭载催化剂(Pt/C、Pd/C、Ru/C、Rh/C)、反应时间、温度以...  相似文献   

4.
生物油脂精炼制备柴油新方法的研究进展   总被引:5,自引:4,他引:1  
综述了以甘油三酯为原料的生物质柴油精练新方法。重点介绍了脂肪酶催化、催化热裂解、催化加氢3种途径的特点和现状:其中脂肪酶催化是制备生物柴油环境友好的生产工艺,是目前最有产业化前景的制备技术;而催化热裂解、催化加氢目前尚在研究阶段,这两种制备方法所得到的燃料油性能较好,与化石燃料油组成及燃料性质接近。同时指出了3种制备方法存在的问题,并展望了3种生物质柴油制备方法各自的发展方向。  相似文献   

5.
以脂松香为原料,改性Pd/C为催化剂和200号油为溶剂进行松香催化加氢反应的研究.采用改进搅拌器类型、加入200号溶剂油、提高搅拌速度大于600 r/min和改变催化剂粒径为10~20 μm的方法消除加氢过程中内外扩散的影响,利用DB-5毛细管气相色谱法在线采样跟踪分析在压力为5 MPa、温度为403~433 K条件下反应体系组成随时间的变化关系,对松香主要成分枞酸加氢反应过程进行拟均相动力学研究.结果表明,松香催化加氢的反应速率与枞酸浓度呈一级反应,其动力学方程为r=l.13×105exp(-5.904×103/T)C1,活化能为4.909×104 J/mol.  相似文献   

6.
综述了近年来国内外纤维素水解加氢耦合反应制备多元醇的研究新进展,介绍了酸、高温水和离子液体分别与金属加氢催化剂构成的3种复合催化体系下的水解加氢反应,梳理了当前纤维素制多元醇催化技术,并进行了展望,可为纤维素转化为多元醇的理论和应用研究提供参考。  相似文献   

7.
介绍了木质纤维素生物质催化转化制取长链烷烃的反应路径。主要从木质纤维素的水解制得平台化合物,中间产物通过羟醛缩合、羟化烷基化、酮化、自身缩合等途径进行加氢脱氧等多步骤合成长链烷烃。阐述了各步转化的反应机理、产物控制途径和相应的催化剂体系,并从技术角度对该领域的研究进行了展望。  相似文献   

8.
第二代生物航空燃油的关键技术分析和进展动态   总被引:1,自引:0,他引:1  
概述了第二代生物航空燃油的技术现状和进展动态,着重讨论了生物丁醇/异丁醇脱水-聚合技术、木质纤维素水解-水相重整催化合成技术、油脂加氢脱氧-裂化异构两段加氢技术和生物质气化费托合成技术。介绍了生物丁醇/异丁醇、麻风果油、亚麻荠油和海藻油等影响生物航空燃油成本的原料开发现状,以及国内外在建的示范装置,分析了第二代生物航空燃油的技术特点及价格竞争力,并展望了其未来发展方向。  相似文献   

9.
木质素是由烷基化的甲氧基苯酚通过氧或碳连接的高度交联的大分子,可用于制备高附加值的燃料和化学品。以来源广泛的木质素为原料制备烃类化合物具有重要的研究价值和良好的应用前景。木质素催化热解是制备烃类化合物的主要方法之一,也是木质素降解研究中的重点和难点,已经受到了人们越来越广泛的重视。笔者概述了近年来木质素原料(含模型物)制备烃类化合物的研究成果,包括木质素转化烃类化合物的催化体系、溶剂体系、烃类化合物尤其是单环芳烃(MAHs)得率和选择性的调控以及利用木质素制备烃类化合物的其他方法,着重介绍了木质素催化裂化及催化加氢脱氧制备烃类化合物的催化体系,并总结了木质素在亚/超临界流体及离子液体中烃类转化的最新成果,最后对木质素制备烃类化合物的研究前景进行了展望,以期为生物质资源的综合利用提供参考。  相似文献   

10.
催化加氢制备低氯漂白紫胶及其表征   总被引:1,自引:0,他引:1  
制备和表征了在食品及制药业中广泛使用的天然低氯漂白紫胶.通过在次氯酸钠漂白改性后的紫胶碱性溶液中加入Ni-Fe二元金属催化剂,升温至90℃后,通入氢气,氢气流速为50mL/min,进行加氢离解反应240min,脱除漂白过程中加成到紫胶分子环状萜烯酸双键上的结合氯,从而获得低氯天然漂白紫胶.借助有机元素分析仪、红外光谱及紫外光谱表征了制备的产物结构,探索了催化加氢制备低氯漂白紫胶的反应机理.结果表明:制备的产物氯质量分数为0.44%,同催化加氢脱氯前的2.54%相比不到1/5;在催化加氢过程中主要发生取代反应,漂白过程中结合到紫胶分子上的氯被氢依次取代.  相似文献   

11.
生物质是具有多种用途的重要物质资源。如何开发利用丰富的生物质资源,是我国未来能源可持续发展、经济结构调整的重要课题。本文对吉林省生物质资源状况进行了调查,对生物质的能源产业化状况进行了分析,并对生物质资源的能源化利用提出了对策。  相似文献   

12.
Transgenic trees as a new source for biofuel have brought a great interest in tree biotechnology. Genetically modifying forest trees for ethanol production have advantages in technical challenges, costs, environmental concerns, and financial problems over some of crops. Genetic engineering of forest trees can be used to reduce the level of lignin, to produce the fast-growing trees, to develop trees with higher cellulose, and to allow the trees to be grown more widely. Trees can establish themselves in the field with less care of farmers, compared to most of crops. Transgenic crops as a new source for biofuel have been recently reviewed in several reviews. Here, we overview transgenic woody plants as a new source for biofuel including genetically modified woody plants and environment; main focus of woody plants genetic modifications; solar to chemical energy transfer; cellulose biosynthesis; lignin biosynthesis; and cellulosic ethanol as biofuel.  相似文献   

13.
电催化是一种可以将电能转化为化学能的清洁、高效转化技术.在生物质精炼的各种策略中,电催化主要通过电子从电极表面转移到反应底物,在阳极和阴极分别发生氧化和还原反应,将生物质衍生物转化为高附加值的产品.总结了几种代表性的木质纤维生物质衍生物,如糠醛、5-羟甲基糠醛(HMF)、木质素及其衍生物等,通过电催化反应转化为高附加值...  相似文献   

14.
我国林木生物质燃料的发展现状与对策   总被引:4,自引:1,他引:3  
随着能源消耗量的不断增加, 有限的常规能源如煤、石油、天然气等, 将日趋紧缺, 我国石油资源不足的问题也将更为突出。目前我国已经成为世界第2大石油进口国, 2004年全年石油进口量达1.4亿t, 占总需求量的1/3多, 我国石油供应对国际石油市场的依赖程度将不断加大。因此, 寻找新的可持续的能源对于我国来说意义特别重大。文中总结了国内外发展生物质特别是林木生物质燃料的现状和经验, 对我国林木生物质燃料产业的发展提出了建议。  相似文献   

15.
Second-generation biofuels are often seen as essential element in the future bioeconomy strategy. Countries with extensive forest resources such as Norway often view wood as preferred bio-feedstock, yet the effects of wood demand on assortments of harvested wood and other wood-based industries are unclear. Focusing on the importance of feedstock choice, we analyse the impacts of establishing a second-generation medium-scale biofuel plant in Norway. For the analysis, a dynamic forest sector model where the choice of tree species, wood assortments, production of bioenergy, and forest industry products are explicitly included, was applied. We find the optimal biofuel feedstock mix to be dominated by softwood chips from pulpwood comprising 48% of total biomass inputs in 2030 and increasing to 67% by 2055, followed by hardwood chips from birch, comprising initially 34% of total biomass inputs and 16% by 2055. The proportion of harvest residues remained constant at about 18% over time and roundwood was not used at all for biofuel production. Despite the additional demand for chips, the single medium-scale biofuel plant will have only minor effects on existing forest industries and harvests in Norway, as the domestic impact is dampened by changes in foreign trade flows, especially of chips.  相似文献   

16.
对不同林业剩余物的棒状燃料的成型技术进行研究,重点分析进料间隙和进料速度对不同材性、粒度的林业剩余物的成型效果.结果表明:1)所有的林业剩余物只要将其含水率控制在15%~25%之间,最大粒度的宽、厚规格不超30 mm,通过调整进料间隙和速度均可加工成棒状燃料.2)进料间隙与原料粒度呈负相关,进料速度又与进料间隙呈负相关.即木屑、竹屑等粒度小的物料进料间隙要大,可调至4~5 mm,进料速度应控制在中速或中速以下(电机频率为6Hz或6 Hz以下);而杂灌、油茶果壳等粒度较大的物料进料间隙要小,可调至1~3 mm,进料速度应控制在较高速或高速间(电杌频率为8~11 Hz).3)成型燃料的密度取决于成型时的压力.通过选用孔长径比大的环模或控制进料间隙和进料速度来调节成型时的压力,可使不同林业剩余物的棒状燃料密度达到1 g/cm3以上.4)原料的物质组成和性质是成型燃料热值的决定因素.锯末、竹屑的棒状燃料热值在4 000 kcal/kg左右,而杂灌和油茶果壳一般在4 000 kcal/kg以下.  相似文献   

17.
In sub-Saharan Africa(SSA), the main goals behind the development of a biofuel industry are employment creation and income generation. Jatropha(Jatropha curcas L.) has emerged as a candidate for biodiesel production. It is a non-edible oil producing, drought-resistant plant that can be grown on marginal land with limited water and low soil fertility. However, these are also attributes that typify weedy and invasive plant species. Adding to these concerns are the general questioning of whether biofuel production will reduce Greenhouse gas(GHG)emissions globally. Currently, there is limited information on the potential invasiveness of many biofuel crops, and in particular, the potential risks of cultivating Jatropha. This paper aims to assess the benefits and risks, especially risks,of growing Jatropha for biodiesel production. Jatropha should be screened through a science-based risk-assessment procedure to predict the risk of becoming invasive before it is released for large-scale commercial cultivation.The net GHG savings can be achieved through the cultivation of Jatropha, considering two main factors: no landuse change and crop management without chemical fertilization.  相似文献   

18.
In sub-Saharan Africa (SSA), the main goals behind the development of a biofuel industry are employment creation and income generation. Jatropha (Jatropha curcas L.) has emerged as a candidate for biodiesel production. It is a non-edible oil producing, drought-resistant plant that can be grown on marginal land with limited water and low soil fertility. However, these are also attributes that typify weedy and invasive plant species. Adding to these concerns are the general questioning of whether biofuel production will reduce Greenhouse gas (GHG) emissions globally. Currently, there is limited information on the potential invasiveness of many biofuel crops, and in particular, the potential risks of cultivating Jatropha. This paper aims to assess the benefits and risks, especially risks, of growing Jatropha for biodiesel production. Jatropha should be screened through a science-based risk-assessment procedure to predict the risk of becoming invasive before it is released for large-scale commercial cultivation. The net GHG savings can be achieved through the cultivation of Jatropha, considering two main factors: no land-use change and crop management without chemical fertilization.  相似文献   

19.
1 Introduction Due to global warming caused by excessive use of fossil fuel resources, renewable biomass resources will become more important in the future as alterna- tives to fossil resources. Therefore, technologies that can convert biomass to valuable liquid fuels and chemicals will be important for solving our energy and environmental problems.Thus, in our laboratory, several research projects on biofuels have been carried out in order to establish bioenergy systems, by means of supercrit…  相似文献   

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