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生物质热解制备木醋液及其性质研究 总被引:2,自引:0,他引:2
生物质热解制备木醋液及其性质研究 《燃料化学学报》2015,43(12):1439-1445
对杉木屑、棉杆、竹屑三种生物质热解制得的木醋液产率、基本理化性质及其有机成分进行了分析研究。结果表明,三种生物质原料在350℃下热解制得的粗木醋液、精制木醋液产率相差不大,相同条件下氯化钾浸渍处理后的杉木屑热解所得的粗木醋液、精制木醋液的产率有所降低。三种原料制得的精制木醋液的理化性质不同,杉木屑木醋液的pH值最小,密度最大,竹屑和棉杆木醋液的有机酸含量相对较高。采用GC-MS对精制木醋液中的有机成分进行了分析,结果表明,杉木屑木醋液中的主要组分为酸类、酚类和酮类化合物,棉杆和竹屑木醋液中的主要组分除这三类有机物质外,还含有相对含量较高的醇类化合物。酸类和酚类化合物在三种木醋液中的相对含量依次是竹屑 >棉杆 >木屑;酮类的相对含量依次是木屑 >棉杆 >竹屑。氯化钾处理后的木屑热解所得的木醋液中主要组分酚类和酮类化合物的相对含量有所降低,酸类化合物的相对含量增加,主要表现为乙酸相对含量的增加。与杉木屑木醋液相比,KCl处理后的杉木屑木醋液中的醇类化合物相对含量增加了1倍左右。 相似文献
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阔叶树皮木醋液与木焦油有机成分的气相色谱分析 总被引:2,自引:0,他引:2
运用气相色谱对阔叶树皮木醋液及木焦油水提取液的有机成分,如醇类、羧酸类、酮类、酚类等进行了定量分析.结果表明,木醋液随着蒸馏处理,甲醇、乙醇、丙酮等低沸点物质主要分布在前馏液中,2,6-二甲氧基苯酚、甲基环戊烯醇酮、2-甲基-3-羟基-4-吡喃酮等高沸点物质主要分布在残馏液中.通过阔叶树皮木醋液及木焦油水提取液的两种主馏分所含有机成分的定量分析比较,表明除甲醇、乙酸、丙酸、2-呋喃醛等成分以外,二者具有相似的化学成分组成. 相似文献
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《燃料化学学报》2021,(2)
为了实现木醋液的高值化利用,在固定床反应器中,进行木醋液催化重整制氢实验,采用浸渍法制备一系列不同Co添加量的Ni基催化剂,以产氢率、碳转化率、H_2选择性和积炭量为主要评价指标,探究液时空速、反应温度、镍钴比等工况对木醋液催化重整制氢的影响,同时采用XRF、H_2-TPR、SEM及元素分析等方法对催化剂进行了表征。结果表明,液时空速增加,产气量增大,但液时空速过高会加速催化剂失活。高温有利于木醋液的催化重整制氢反应,温度到达900℃时,氢气产率最高。随着钴添加量的增加,反应产生的积炭降低,但氢气产率也会有所下降。因此,当液时空速为60 h~(-1),温度为800℃时,采用Ni-0.5Co/Al_2O_3催化剂,最适于木醋液的催化重整制氢实验。 相似文献
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《分析试验室》2016,(7)
以上海市闵行地区的大气细颗粒物PM_(2.5)为研究对象,综合多种分析测试手段对颗粒物的成份进行分析,以识别PM_(2.5)中主要污染物的来源。采用扫描电镜和透射电镜技术观察颗粒物的形貌特征,红外光谱技术识别颗粒物中的特征官能团,再结合碳分析仪,电感耦合等离子体质谱,离子色谱和气相色谱等技术对颗粒物中的元素碳和有机碳、无机金属元素、无机水溶性离子及有机化合物PAHs进行定量分析。结果表明PM_(2.5)是由大量的微米颗粒物及部分超细颗粒物组成,颗粒物主要以烟尘聚集体的形式存在;PM_(2.5)中有无机盐类和有机化合物的官能团共存在,有机官能团主要为羧基和芳烃化合物,无机化合物主要为硫酸盐和氨类化合物;各化学组份的质量分数表明了二次离子(SO_4~(2-),NO_3~-,NH_4~+)和有机碳是PM_(2.5)中的主要污染物,并明确解析了PM_(2.5)中各种污染来源的分担率。 相似文献
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当归化学成份分析研究——根部非挥发性成份分析 总被引:1,自引:0,他引:1
本文报导了甘肃岷县当归根部非挥发性成份的分析结果。共鉴定出37个有机成份,其中15种未见报导。用等离子体发射光谱检出当归中13种微量元素。 相似文献
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本文从分析方法和应用两方面,对分析科学中的一个重要分叉-剖析技术予以综合介绍。从方法论看剖析,它充分体现了分析科学综合性的特点、集分离分析、结构分析和成份分析于一体,全面表征物质的结构和成份信息;从应用方面看,它囊括无机,有机,物化和生化等领域中的分析课题,以材料科学、生命科学和环境科学中的各种复杂样品的分析,因此剖析又是把分析科学与合成,加工和应用技术紧密联系的一种系统工程。它的学科地位和广泛的 相似文献
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The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted
indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator
model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was
established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing
analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997. 相似文献
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Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared. 相似文献
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Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position. 相似文献
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Stepkowska E. T. Perez-Rodriguez J. L. Jimenez de Haro M. C. Sayagues M. J. 《Journal of Thermal Analysis and Calorimetry》2002,69(1):187-204
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations
were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples
were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of
hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the
best fitting experimental data.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6. 相似文献