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1.
杉木(日本柳杉)经醋酸水溶液处理后,重量减少。将处理前后柳杉木材在4℃下进行炭化,得到了木醋液、木焦油和木炭。与未处理材相比,处理材木醋液的收率增加,而木焦油和木炭的收率减少。处理液的醋酸浓度增加后,木醋液和木焦油的收率几乎不变,但木炭的收率稍微减少了。用毛细管气相色谱法对木醋液的成分进行了定量分析。与未处理材相比,处理材木醋液中糠醛(呋喃甲醛)及5-羟甲基糠醛的收量增加,而羧酸类、苯酚类、邻苯二酚、愈创木酚类及麦芽酚的收量几乎不变。当醋酸浓度从0增至3%时,糠醛的收量随着增加,但是当醋酸浓度从3%增至30%时,其收量却几乎不变。  相似文献   

2.
柳杉木材边材木醋液中的成分研究   总被引:1,自引:0,他引:1  
用毛细管气相色谱法对日本柳杉木材边材炭化得到的木醋液中的37种成分进行定性和定量分析.结果表明,醇类、酮类、羧酸类、呋喃类、苯酚类及愈创苯酚类是其主要成分.用溶剂萃取-硅胶柱层析法进一步分离处理木醋液,纯化出炭化过程中产生的手性脱水内醚糖-左旋葡聚糖(LGA,1,6-脱水-β-D-葡萄糖),但其不能被毛细管气相色谱法检...  相似文献   

3.
木醋液在日本农林业上的应用   总被引:4,自引:0,他引:4  
木醋液是水溶性的液体混和物,它在木材热解时产生;在木炭生产中能够容易得到大量的木醋液。19世纪末,木醋液主要作为生产醋酸、甲醇的原料;随着化学合成工业的发展,它逐渐被廉价且纯度高的合成产品所取代;目前,在世界各地几乎没有利用它。  相似文献   

4.
柞树木醋液酚类物质的组分分析   总被引:4,自引:1,他引:3  
采用常规方法测定了柞树木醋液的基本参数,所得木醋液为黑褐色且带有烟焦味,pH值4.06,有机酸含量(以醋酸计)5.20%,密度(20℃)1.026 0 g/cm3,木炭粉吸附法精制得率90.7%.采用分配法将柞树木醋液系统地划分为酸性物、酚类物和中性物,并利用GC-MS联用仪对酚类物进行了组分分析.结果表明,酚类物中的主要组分是苯酚3.60%、2-甲基苯酚1.20%、1,2,3-三甲氧基苯12.82%、2,6-二甲氧基苯酚34.41%和4,6-二(1,1-二甲基乙基)-2-甲基-苯酚35.97%.该分析对柞树木醋液产品品质基准的制订具有重要意义.  相似文献   

5.
木醋液的精制及有机成分研究   总被引:33,自引:0,他引:33  
为了确定酸性饮料添加剂用木醋液和禽畜饲料以及饮水添加剂用木醋液的工艺条件,利用GC/MS对木醋液在精制过程中其有机成分的变化情况作了详细分析,其中对人体和禽畜有害的成分,则以苯酚为代表进行了详细的跟踪分析。研究结果表明,选用较简单的典型精制单元互相搭配,可以除掉木醋液中较难除掉的苯酚等有害成分。经过精制,苯酚含量由原始木醋液中的836mg/L降低到几乎检测不到的程度。  相似文献   

6.
采用常规方法测定了柞树木醋液的基本参数,所得木醋液为黑褐色且带有烟焦味,pH值4.06,有机酸含量(以醋酸计)5.20%,密度(20℃)1.0260g/cm^3,木炭粉吸附法精制得率90.7%。采用分配法将柞树木醋液系统地划分为酸性物、酚类物和中性物,并利用GC—MS联用仪对酚类物进行了组分分析。结果表明,酚类物中的主要组分是苯酚3.60%、2-甲基苯酚1.20%、1,2,3-三甲氧基苯12.82%、2,6-二甲氧基苯酚34.41%和4,6-二(1,1-二甲基乙基)-2-甲基-苯酚35.97%。该分析对柞树木醋液产品品质基准的制订具有重要意义。  相似文献   

7.
以杉木屑为原料,采用干馏法制备杉木油,分别得到干馏油、木醋液、焦油和木炭,产率分别为4.0%、38.0%、14.3%、28.8%,除此之外还得到不凝性可燃气,产率为15.0%。对杉木屑干馏油、木醋液和不凝性气体的性质、组成进行研究,结果发现:杉木屑的固液产品总转化率达到了80%以上;杉木干馏油的主要组成为α-柏木烯29.36%、β-柏木烯11.87%、柏木醇12.10%等;木醋液的主要成分为1-甲基亚乙基环己烷24.07%、乙酸19.77%、4-乙基愈创木酚11.71%、糠醛8.06%等;不凝性可燃气主要由H_2、CO和CH_4组成。  相似文献   

8.
木炭业产品开发及利用(I)——神奇的木醋   总被引:1,自引:0,他引:1  
1 前言木炭业历史悠久 ,然而详细了解炭化产品种类的人似乎不多 ,人们熟悉的往往是黑黑的木炭 (黑炭 )。从资源充分利用和产品附加值提高考虑 ,现拟讨论木炭业的产品开发及利用问题。首先让我们对一组木材炭化组成元素的数据进行分析。数据经整理如表1。表 1 木材及其炭化元素组成表(单位 :% )木材木炭木醋·木焦油·木气计 10 0 0 2 7 2 72 8碳 5 0 0 2 5 0 2 5 0氧 4 4 0 1 5 4 2 5氢 6 0 0 7 5 3[注 ]①表中数据系指生产黑炭的情况。②木醋产量大约占木材量的 5 %。从表 1可见 ,在制备黑炭的情况下 ,只有1 / 4的木材成分转化…  相似文献   

9.
不同林龄柚木人工林心边材生长变异特征   总被引:1,自引:0,他引:1  
【目的】探明广西大青山林区不同林龄柚木人工林心、边材量及心材年轮数和心材高度的生长变异特征,以期为了解该区域柚木心边材发育特征、心边材量预测及高质量、大径级柚木目标树的高效培育提供基础数据和科学依据。【方法】以广西大青山10、18、31和41年生柚木人工林平均木的解析木为研究对象,对心、边材的方位变异和心、边材量的株间差异进行方差分析,并采用曲线估计法拟合心、边材量与横截面直径、总年轮数之间的回归模型,研究柚木心、边材生长变异特征。【结果】各林龄柚木树干心材半径主要为北向最大,边材宽度则主要为北向和东向最大,各林龄内,树干4个方位的心材半径、边材宽度均无显著差异(P0. 05)。各林龄柚木心材半径、心材面积和边材面积均表现为随树高增加持续减小,边材宽度在树干基部(0~1 m)明显偏大,且在树干一定区域内保持相对稳定。林分心、边材量总体表现为随林龄增加而增大,不同林龄林分间除边材宽度差异不显著外(P0. 05),心材半径、心材面积和边材面积均存在极显著差异(P0. 01)。横截面心、边材量随横截面直径和总年轮数的增加而增加,其中与横截面直径的相关性高于总年轮数,而总年轮数对心材发育早期影响较大。各林龄内,柚木个体的心边材量、心材消失最大高度存在较大的株间变异,其中,心材面积和边材面积的变异程度相近,心材半径、边材宽度和心材消失最大高度的变异程度相近。柚木最早在4年生时开始有心材形成,不同林龄的心材年轮数均表现为随总年轮数增加而增加,总年轮数可解释心材年轮数80%以上的变化,10、18、31和41年生柚木心材年轮数年均增长速率分别为0. 9轮、0. 7轮、1. 0轮和1. 0轮。柚木心材消失最大高度、心材消失的相对高度均与林龄呈正相关关系,即随着林龄的增大,心材在树干更高处消失。【结论】柚木心材形成初始年龄最早为4年生,属心材形成较早的树种。各林龄内,方位对柚木心、边材影响较小。柚木的心材半径、心材面积、边材面积和心材消失最大高度,均表现随林龄增加而显著增加,而边材宽度无显著变化。柚木横截面直径可以更好地解释横截面心、边材量的变化,总年轮数仅能解释柚木前期(31年生)心材量的变化。研究认为41年生柚木心材仍有很大增长潜力,若要达到高质量、大径级的培育目标,还需要更长时间的培育。  相似文献   

10.
木质炭化物对挥发性有机污染物吸附性能的研究   总被引:1,自引:0,他引:1  
黄彪  高尚愚 《林业科学》2004,40(3):140-143
本文探讨了炭化温度对木材炭化物的得率 ,还原性 ,pH值 ,苯蒸气、三氯甲烷蒸气吸着率的影响。结果表明 ,30 0~ 90 0℃的炭化温度下 ,木炭的得率随着炭化温度升高而下降 ,并在 6 9 8%~ 2 0 6 %的范围内变化。炭化温度为 70 0℃时 ,产物木炭的比表面积最大 ;80 0℃时 ,木炭元素组成中的 (C H) O的摩尔比值最大 ,这意味着该木炭的还原性最大。木炭水溶液的pH值随着炭化温度上升而增加 ,炭化温度小于 5 5 0℃时呈酸性 ,大于 5 5 0℃时为碱性。炭化温度对木炭环境净化能力有显著的影响 ,6 0 0℃炭化得到的木炭对三氯甲烷蒸气的吸附率最大 ,高达8 5 % ,约为 30 0℃时的 5倍 ;80 0℃炭化得到的木炭对苯蒸气的吸附率最大 ,达 5 % ,约为 30 0℃时的 5倍左右。  相似文献   

11.
Summary NPA, applied in a 2–3 cm band around the middle protion of 2- or 3-year-old internodes of three vertically-oriented six-year-old Sugi trees (Cryptomeria japonica D. Don), brought about abnormal thickening all over the upper segment from the NPA treatment. Xylem tissues above and below the treatment, as well as at the treated area itself, was examined by ordinary light microscopy and by scanning electron microscopy. The results obtained seemed to indicate that the tissue formed after treatment in the upper segment of the stem was true compression wood. In the lower segment of the stem, no abnormal tissue but a small amount of latewood-like tissue was produced after treatment.Referring to the previous studies in which morphactin, another IAA transport inhibitor, has induced compression wood, we consider it likely that compression wood formation must be induced by high concentrations of endogenous IAA, which could be brought about by blockage created not only by NPA and morphactins, but also by IAA transport inhibitors in general.  相似文献   

12.
为了研究醋酸水溶液处理给杉树材重量带来的变化,使用醋酸水溶液对杉树材进行了处理。结果发现处理后杉树材重量的减小量大约等于抽出物的重量,而且随着醋酸水溶液浓度的增加而增加。利用傅立叶变换红外光谱法对处理后的杉树材及抽出物进行了光谱分析。从处理后杉树材的光谱图可以观察到3400cm-1附近的OH伸缩振动及1510cm-1附近的木质素中苯环C=C伸缩振动的吸收强度有增加倾向。从醋酸水溶液抽出物光谱图可以发现用浓度30%醋酸水溶液处理时木质素被溶出。图2表2参6。  相似文献   

13.
Sugi sapwood samples were processed with aqueous solution of acetic acid in order to find the response of the weight of sugi sapwood and the treatment of aqueous solution of acetic acid. The result showed that loss of weight for the treated sugisapwood was about equal to yield of extracts from sugi sapwood, and increased with the increment of the concentration of aqueous solution of acetic acid. Fourier transform infrared spectroscopy spectra changes of the treated sugi wood and extracts from sugi sapwood were analyzed by FT-IR spectroscopic technique. Increasing tendency of absorption intensities of the stretching vibration at 3 400 cm^-1 of hydroxyl group (OH) and C=C in lignin stretching vibration at 1510 cm^-1 of benzene ring inlignin were observed from FT-IR of the treated sugi sapwood. From FT-IR spectra of extracts from sugi sapwood by aqueoussolution of acetic acid, the dissolution of lignin was observed during the treatment with 30% acetic acid solution aqueous.  相似文献   

14.
综述了矿质元素在针叶树干内的径向、轴向和细胞壁内的分布特点;影响矿质元素在树干内分布的主要因素。评述了以树木中矿质元素的分布特征进行树木分类的可行性,以及树干年轮间元素的变化值作为评价环境年代变迁指标的有效性。并对今后的研究方向提出了建议。  相似文献   

15.
Summary Tar and charcoal could be produced in high yields from bagasse by applying a rapid continuous pyrolysis process at a relatively low temperature. The ether extractives of the pyrolytic tar and oil amounted to 9.4% based on bagasse. Phenols represented 79% of these extractives. Gas chromatographic separation showed that guaiacol and its derivatives constituted 38% of the identified simple phenols. There were much smaller amounts of syringol and none at high pyrolysis temperatures. Depithing did not reduce the ash content of the charcoal, but it yielded an environmentally clean charcoal containing practically no sulfur or nitrogen. It was necessary to remove the fine particle size fraction of the bagasse after grinding in order to reduce the ash content of the charcoal. The carbon content of the charcoal increased rapidly with increasing temperature, and reached 96% at 720°C. The charcoal had a remarkably high adsorption capacity despite the fact that it had not been subjected to any activation treatment.The first two authors wish to express their thanks to the Institut für Holzchemie, Hamburg for providing facilities during this work and to the Alexander von Humboldt-Stiftung, and the Deutsche Forschung Gemeinschaft for their financial support  相似文献   

16.
Heat treatments change the chemical and physical properties of wood and dimensional stability and hygroscopicity are affected as a result of modifications of wood cell components. This study evaluated the water absorption of wood specimens treated with boron compounds followed by heat treatment. Sugi (Cryptomeria japonica D. Don) sapwood specimens treated with either boric acid (BA) or disodium octoborate tetrahydrate (DOT) solutions were heat-modified at either 180° or 220°C for 2 or 4 h. Carbohydrate composition and water absorption of the specimens were then measured and compared with those of untreated and unheated specimens. Wood carbohydrates were significantly degraded in the specimens after heat treatment. The heat treatment evidently decreased the water absorption and the heat-modified specimens absorbed less water than unheated specimens. The higher the treatment temperature and the longer the treatment time, the lower the amount of absorbed water. The boron-treated and heat-modified specimens, however, showed increased water absorption due to the hygroscopic properties of BA and DOT.  相似文献   

17.
Thermal treatment of chromated copper arsenate (CCA) impregnated waste wood is a way to utilize the energy resource of the wood and at the same time to reduce the volume of the waste. An issue of concern in relation to the thermal treatment is As emission to the air. Meanwhile, there is still a matter to cope with when methods to avoid As emission are implemented: the residues with increased concentrations of Cu, Cr and As. In the present paper two different residues after thermal treatment are characterized: a mixed bottom and fly ash from combustion of CCA impregnated wood, and a charcoal from pyrolysis of treated waste wood. By SEM/EDX it was seen that the charcoal still showed wood structure with both tracheids and rays and that Cu, Cr and As were found inside this wood structure. Cu was found alone while Cr and As were often found together. By chemical analysis it was found, too, that the charcoal contained a high concentration of Zn, probably from paint. Chemical extraction experiments in HNO3 were conducted with the charcoal and it was found that the order of extraction (in percentage) was Zn > Cu > As > Cr. A SEM/EDX investigation of the mixed ash from combustion showed the presence of small particles with wood structure with elevated Cu and Cr concentrations, but most particles were irregular shaped matrix particles rich in Si, Al and K. Cr was abundant in many different particles including the lignin skeleton of the small, unburned wood pieces, but also inside silica-based matrix particles. Ca was often found associated with char-like (porous) particles, indicating that Ca-arsenates had been formed during combustion. Cu was often associated with Cr in the unburned wood pieces, whereas it was less abundant inside the silica-based matrix particles. Cu was also found in an almost pure form in a small layer on the surface of some matrix particles indicating condensation of volatile Cu species. Chemical extraction with inorganic acids showed the order of percentages mobilized as: As > Cu > Cr.  相似文献   

18.
Wood meals of Sugi (Cryptomeria japonica D.Don) passing 2.0 mm and retained on 1.0 mm mesh screens were milled along with acetic anhydride (AA) and pyridine as a catalyst in a high-speed vibration rod mill at ambient temperature. The weight percent gain (WPG) of the chemically modified wood was calculated based on the yield after washing with deionized water. The effects of amounts of AA and catalyst added, pulverization time, and saponification of the acetylated wood on WPG were examined. In addition, FT-IR analysis, and water vapor adsorption and desorption tests were performed as functions of the WPG. Increases in WPG, the acetyl contents of the acetylated wood after saponification, changes in the FT-IR spectra after pulverization, and the water vapor sorption isotherms showed that the one-step acetylation systematically modified the hydroxyl groups of the wood into acetyl groups. Up to 38 % WPG was obtained at 100 phr AA and 15 phr catalyst, and 120 min pulverization. Pulverization time and the amounts of AA and catalyst added to the wood meals could be adjusted to obtain acetylated wood meal with the desired WPG. These demonstrated that the mechanochemical acetylation is a method to prepare acetylated wood meals with high WPG at less reaction time and required AA addition.  相似文献   

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