共查询到20条相似文献，搜索用时 234 毫秒
1.
油茶壳制活性炭的研究 总被引：13，自引：0，他引：13
以油茶壳为原料，用物理法(水蒸汽为活化剂)制备活性炭。研究了活化温度、活化时间、水蒸汽用量等对活性炭的得率、碘吸附值和亚甲基蓝吸附值的影响。确定了用油茶壳制备活性炭适宜的工艺条件为：活化温度为850℃、活化时间为2．5h，水蒸汽用量为210g。在此工艺条件下所制取的油茶壳活性炭的得率为33．7％。活性炭的碘吸附值968mg／g，亚甲基蓝吸附值180mg／g，比表面积935m^2／g。 相似文献
2.
3.
采用正交试验设计,研究活化温度、活化时间和水蒸气用量对活性炭吸附性能、活化得率和固定碳含量的影响.并分析活性炭的孔结构特征,结果表明竹活性炭的低温氮气吸脱曲线属于典型的微孔结构活性炭的吸附曲线,其BET和微孔比表面积、总孔和微孔容积的数值是原料竹炭的2倍左右,但活化时间的延长对活性炭的微孔结构参数影响较小,不影响低分子有害物质的去除.得到最佳活化工艺条件为:活化时间1.5h、活化温度900℃、水蒸汽用量430～480 g·h-1.制得竹活性炭具有较高的碘、亚甲基蓝和苯酚吸附值,优异的孔结构,活化得率可达45％,强度93.76％.最佳工艺制备的竹活性炭达到烟用活性炭国家烟草行业标准,基本达到净化空气用煤质颗粒活性炭国家标准,高性能竹炭制备烟用竹活性炭是可行的. 相似文献
4.
氯化亚铜催化的月桂烯氢氯化反应的研究（I）：产物分布和反应机理 总被引：1，自引：0，他引：1
研究氯化亚铜催化的月桂烯氢氯化反应的产物分布和反应机理，考察了催化剂和稀释剂对产物分布的影响。结果表明：（１）月桂烯的氢氯化反应生成月桂烯基氯、芳樟基氯、橙花基氯、香叶基氯和α－松油基氯５种单氯化物，产物中３种烯丙基型氯化物的含量约达到９０％；（２）月桂烯的氢氯化反应是通过共轭双键吸附在催化剂表面上，并与吸附的氯化氢形成表面活化络合物进行的，该表面活化络合物经两个共振结构的碳正离子中间体分别生成芳 相似文献
5.
将环氧活化的纤维素纤维(CPGMA)分别在水介质和二甲基酰胺(DMF)介质体系中进行多胺化有机合成反应，考察反应介质、胺浓度、反应时间、温度、液比和初始环氧基含量等对胺化反应的影响。研究结果表明：DMF作为反应介质、温度为60℃时最有利于胺化反应进行，纤维增重与胺浓度之间符合线性关系。在DMF介质中，胺化反应在1 h之内达到饱和，反应液比增大不利于胺化反应的进行，CPGMA的环氧基含量越高越有利于胺化反应进行。600℃时，CPGMA(接枝率198%)的残余量为5.1%,而胺化改性后的CPGMA-EDA残余量为16.8%,纤维热稳定性提高。固体核磁13C CP/MAS NMR谱图中5′环氧基上的叔碳峰的消失及2′季碳和6′环氧基上亚甲基碳峰强度的减弱，均验证了胺化反应的成功进行。 相似文献
6.
研究氯化亚铜催化的月桂烯氢氯化反应的产物分布和反应机理，考察了催化剂和稀释剂对产物分布的影响。结果表明：（１）月桂烯的氢氯化反应生成月桂烯基氯、芳樟基氯、橙花基氯、香叶基氯和。α－松油基氯５种单氯化物，产物中３种烯丙基型氯化物的含量约达到９０％；（２）月桂烯的氢氯化反应是通过共轭双键吸附在催化剂表面上，并与吸附的氯化氢形成表面活化络合物进行的，该表面活化络合物经两个共振结构的碳正离子中间体分别生成芳樟基氯、橙花基氯和香叶基氯。并对提出的反应机理进行了讨论。 相似文献
7.
KOH活化木质碳纤维的孔隙结构及其成孔机理 总被引：1，自引：0，他引：1
由于化石资源价格昂贵且面临着日益枯竭的危机,以木材等生物质资源代替化石资源生产活性炭纤维已势在必行。KOH活化制备的木质活性炭纤维孔隙结构较为单一,极大地限制了其应用领域,为了更好地对其孔隙进行调控,需对木质活性炭纤维的孔隙结构生成及其演变有一个全面的认知。笔者总结了原料以及KOH为活化剂处理木质活性炭纤维的工艺因子,如炭化温度、碱碳比、浸渍时间、活化时间对孔结构的生成、扩展的影响,并重点归纳了KOH活化木质活性炭纤维孔隙结构的生成及演变机制。在此基础上,凝炼出KOH活化木质活性炭纤维研究领域存在的诸如木质原料主化学成分是如何参与活性炭纤维孔隙构造,以及在KOH活化处理过程中孔隙结构的中间反应,即活化反应过程或生成路径的科学问题,同时指出了今后该领域应重点研究的几个方向。 相似文献
8.
漾濞泡核桃壳制活性炭试验 总被引：4，自引：0，他引：4
漾濞泡核桃壳是经加工取仁后的剩余物，占核桃重量的４２％～４６％。本研究在于摸索其制造活性炭炭化和活化的工艺条件，试验结果表明；漾濞泡核桃壳经过炭化、水蒸汽活化，可制成净水用颗粒活性炭、味精脱色用颗粒活性炭和粉状活性炭等３个品种，主要技术指标都符合国家标准；漾濞泡核桃壳容易活化，不但活化温度低，而且活化时间也短，温度在８１０℃时活化１５０ｍｉｎ就能制得碘值在１０００ｍｇ／ｇ以上的优质活性炭；漾濞泡核桃壳较薄，宜于制造小颗粒活性炭，大约１０ｔ泡核桃壳可生产１ｔ活性炭 相似文献
9.
10.
行为试验发现侧柏饵木对双条杉天牛有很强的引诱作用。采用顶空吸附采样方法林间采集侧柏不同部位的挥发性成分,经热脱附吹扫捕集-气相色谱-质谱联用分析,发现侧柏释放的挥发性成分主要由脂肪族的绿叶成分和单萜烯组成。固相微萃取和水蒸汽蒸馏采集侧柏韧皮成分,分析发现其主要成分由单萜烯、倍半萜烯及其衍生物组成,两种采样方法的采样效果有一定的差异。触角电位研究表明,双条杉天牛触角对挥发性绿叶成分正戊醇、正己醇、2-乙基-1-己醇和1-辛烯-3-醇有很强的触角电位反应;对醛类化合物触角电位反应较弱;对单萜烯类化合物香桧烯、侧柏醇和(-)-柠檬烯有很强的触角电位反应。双条杉天牛对小蠹虫的信息素都有很强的触角电位反应,特别是对3-甲基-2-环己烯-1-醇及其酮类化合物。含6个碳或8个碳的醇类成分与马鞭草烯酮结合和侧柏挥发性的单萜烯类成分对双条杉天牛寻找寄主的行为可能有很大影响。 相似文献
11.
The durability of isocyanate resins consisting of emulsion-type polymeric diphenylmethane diisocyanate (EMDI) was investigated under constant steam heating. Two kinds of resin, water only-added resin and polyol/water-added resin, were used in this study. The degradation of the resins under steam heating was observed using Fourier transform infrared spectroscopy (FT-IR), weight changes, and thermogravimetric analysis (TGA). FT-IR analysis showed that the degradation reaction of the resins scarcely proceeded for a few hours and then increased significantly. The weights of the resins decreased linearly during steam heating. The thermal stability of steam-treated resins was made clear by TGA. The bond strength reductions of the specimens bonded with the resins were also observed. The best fitting regression function for the behavior of bond strength reduction was determined statistically. The apparent activation energy of each resin was calculated from the regression function, for the half-life period. Considering the calculated values, the adhesion durability of using polyol-added resin was superior to that of using water only-added resin. It was clarified that the durability of the isocyanate resins under steam heating was markedly inferior to that under dry heating.Part of this paper was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, 2000 相似文献
12.
13.
14.
15.
该蒸馏器利用小型蒸汽锅炉输送不同压力的饱和水蒸气直接蒸馏。较常规蒸馏器蒸馏速度快，出油率高，节约燃料和时间。通过对岩桂枝叶蒸馏对比试验，其出油率达到２．２８％，比常规蒸馏器蒸馏时间缩短一半，提高出油率２０％；蒸馏每百公斤枝叶煤耗减少２６．７７％，劳力减少６４．３％，加工费节约５．８８元；加工枝叶量提高２倍以上。 相似文献
16.
Thermoplastic processing of lignin is restricted by its high glass transition temperature (T g). In this study, lignin was modified with polyethylene glycol (PEG) during steam explosion to improve its thermoplastic properties, and the effects of steam explosion and PEG on the chemical structure and thermal properties of lignin were investigated. Structure characterization using Fourier transform infrared spectroscopy showed that hydroxyl and ether functional groups increased and the activity of lignin was improved by steam explosion. In addition, steam explosion treatment was more effective than heat treatment for promoting the reaction of PEG with lignin. Solid-state 13C NMR revealed that PEG was grafted onto lignin. The T g of raw lignin was 164.1 °C; after steam explosion, lignin exhibited more than one T gs. The T g of lignin was reduced when the steam explosion temperature increased and decreased further, to around 60 °C, when PEG was used to modify lignin. Therefore, this work provides an effective approach to reducing the high T g of lignin. 相似文献
17.
36个油茶优良单株综合评价及主要性状分类 总被引：1，自引：0，他引：1
本文采用相关分析法和主成分分析法及因子负荷量图,对36个优良单株的8个主要性状进行相关分析、综合评价及性状分类.结果表明：①3年平均冠幅产量与干出籽率存在极显著的负相关关系,果形指数与鲜出籽率存在显著的负相关关系,鲜出籽率与干出籽率存在显著的正相关关系;②筛选出综合性状表现更好的前10个,分别是：qc7、qc1、mc1、ha6、ha1、qc10、mc12、qc9、ha2、mc2;③将8个主要性状分为3类,分别为出籽率因子、产量因子和果实因子. 相似文献
18.
19.
20.
Md. Nazrul Islam Keisuke Ando Hidefumi Yamauchi Yoshinori Kobayashi Nobuaki Hattori 《Journal of Wood Science》2007,53(5):436-441
Square lumber specimens of laser-incised Douglas fir (Pseudotsuga menziesii Franco) were treated with steam before dipping. Two types of steam (saturated steam and superheated steam), three steam-injection
times (5, 10, and 20 min), four different time intervals (moving time) between steam treatment and dipping (immediate, 3,
10, and 30 min), and four different dipping times (0.5, 1, 3, and 12 h) were used in the study. The maximum absorption was
480 kg/m3 when saturated steam was injected for 20 min and the specimen was immediately dipped into liquid for 12 h. Samples treated
with this condition not only absorbed the maximum amount of liquid but also penetrated over 83.4% and 87.3% of the total area
along and across the grain, respectively. The optimum conditions were then applied to laser-incised sugi (Cryptomeria japonica D. Don) and Japanese larch (Larix leptolepis Gordon) where the absorption of liquid was 415 and 187 kg/m3, respectively. It was shown that initial moisture content below the fiber saturation point was good for passive impregnation.
The absorption of liquid and its distribution in wood indicates that it can be a good preservative treatment method for impermeable
woods. 相似文献