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从6种大孔树脂中筛选了适宜的提取分离甜茶苷的吸附剂,研究了大孔吸附树脂提取甜茶苷的工艺,包括甜茶苷溶液的质量浓度、pH值和流速对吸附过程的影响,解吸剂及解吸温度对解吸过程的影响.结果表明:AB-8树脂是理想的甜茶苷吸附剂,其吸附甜茶苷较理想的工艺条件是:原料液质量浓度约为7.7mg/L,pH值约为8,流速为3BV/h(BV为层析柱中树脂床的体积);理想的洗脱条件为:流速为3BV/h,室温下以70%乙醇溶液为洗脱剂,用量为5BV,或40℃下,以60%乙醇溶液为洗脱剂,用量为4BV.实验室利用该工艺成功地分离出甜茶苷. 相似文献
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利用Mannich反应将黑荆树单宁固定在氯甲基化聚苯乙烯树脂表面,成功地制备出一种新型固化单宁大孔吸附树脂(MARIT),并通过正交试验得出适宜的合成条件.苯酚在MARIT上的平衡吸附数据符合Freundlich吸附等温方程.利用热力学函数关系计算了等量吸附焓、吸附自由能和吸附熵,等量吸附焓在8.95~13.41 kJ/mol之间,推测吸附过程为氢键吸附.比较MARIT对苯酚的水溶液和环己烷溶液中苯酚的吸附性能,及对溶液中苯酚、间苯二酚和邻硝基苯酚的吸附性能,进一步讨论了MARIT对苯酚吸附时的氢键作用. 相似文献
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亚临界水提取协同大孔树脂纯化杨树芽总黄酮 总被引:4,自引:0,他引:4
采用亚临界水提取-大孔树脂纯化联用技术对杨树芽中总黄酮进行提取、纯化,以提取温度、液料比和提取时间为考察因素,以总黄酮的得率为考察指标,采用正交试验优化亚临界水对杨树芽总黄酮的提取工艺;从4种大孔吸附树脂中筛选出对总黄酮有最佳分离纯化效果的一种树脂,研究其对总黄酮静态和动态吸咐以及解吸效果。结果表明,5 MPa下亚临界水提取杨树芽总黄酮的最佳工艺条件为:提取温度180℃、提取时间10 min、液料比30∶1(mL∶g),总黄酮的粗品提取得率为11.83%,纯度为13.16%。通过静态吸附试验筛选出最有效的HP-20树脂分离纯化杨树芽总黄酮,通过动态吸附试验确定应用HP-20树脂吸附分离杨树芽总黄酮的最佳工艺条件为:上样质量浓度为4 g/L,流速为60 mL/h,pH值为2~3,此时吸附量为42.69 g/L洗脱剂乙醇的体积分数为90%,解吸率为93.91%,经纯化后总黄酮的纯度为49.28%。 相似文献
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以蓝莓果提取液为原料,研究了12种大孔树脂对花色苷的静态吸附与解吸效果,对比了5种对花色苷分离效果较优树脂的静态等温吸附曲线,优化了最优树脂分离纯化蓝莓花色苷的工艺技术参数。研究结果表明XDA-7最适用于蓝莓花色苷的分离纯化,最佳吸附工艺是:室温条件下,蓝莓提取液pH值3.0、质量浓度0.94 g/L、流速30 mL/h,最大吸附量15.41 g/L(湿树脂);最佳洗脱工艺是:室温条件下,80%甲醇、pH值3.0、流速60 mL/h、洗脱剂量75 mL,解吸率达92.65%。在该工艺参数下,经XDA-7树脂纯化冷冻干燥所得产品为紫黑色粉末,花色苷纯度由2.20%提高到24.54%,花色苷得率为70.2%,产品色价为121。 相似文献
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Preparation of liquefied wood-based resins and their application in molding material 总被引:9,自引:0,他引:9
Zhang Qiu-hui Zhao Guang-jie Yu Li-li Jie Shu-jun 《中国林学(英文版)》2007,9(1):51-56
To investigate value in use of liquefied wood-based resin applications in molding material, Chinese fir (Cunninghamia lanceolata) and poplar (Populus tomentosa) wood meal were liquefied in phenol. The reactant was co-condensed with formaldehyde to obtain liquefied wood-based resin. For this paper, we investigated the characterization of the resin and its application in molding material. The result shows that the basic properties of liquefied wood-based resin were satisfactory; the bonding strength of plywood prepared with liquefied Chinese fir and liquefied poplar resin can reach 1.54 and 1.00 MPa, respectively. The compression strengths of the molding material prepared with two kinds of liquefied wood resin were 73.01 and 73.58 MPa, almost the same as that of PF resin molding material. The limiting volume swelling of molding material made with liquefied Chinese resin and liquefied poplar resin were 8.5% and 8.3%, thickness swelling rates of water absorption were 3.3% and 4.2%, and the maximum weight ratios of water absorption were 25.9% and 26.2%, respectively. The soil burial test result shows that the weight loss rate of the molding materials made with liquefied Chinese resin and liquefied poplar resin were 8.3% and 9.1% and that of the PF resin molding material was 7.9%. After the soil internment test, the reduction ratio of compression strength of the two kinds of molding material achieved 16.9% and 17.7%, while that of the PF resin molding material was 15.4%. The test results of wood fungi inoculation on the three surfaces of the molding material indicate the breeding rate of molding material prepared with liquefied Chinese resin and liquefied poplar resin were at level 4 and that of PF resin molding material was at level 1 of the ISO standard. 相似文献
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改性松香-缩合单宁酯的制备及性质 总被引:1,自引:1,他引:0
在微波辐照下,以吡啶作催化剂,通过缩合单宁与改性松香酰氯的O-酰化反应,以改性松香和不同级分或树种的缩合单宁为原料,合成了一系列改性松香-缩合单宁酯.利用UV、IR、TG-DTA和元素分析等方法对目标产物进行了分析和表征,并测试了它们的抗氧化性及其钠盐的表面活性.结果表明,改性松香-缩合单宁酯的油溶性普遍好于缩合单宁,在花生油中表现出良好的抗氧化性,且去氢枞酸-毛杨梅树皮缩合单宁酯的抗氧化性能最佳.改性松香-缩合单宁酯的钠盐比缩合单宁的钠盐具有更优良的表面活性,其降低表面张力能力强弱顺序为:HR-WT钠盐>HR-ET钠盐>DR-ET钠盐>DR-WT钠盐>DHA-WT钠盐≈DHA-MET钠盐>DHA-ET钠盐>ET钠盐;不同松香改性产物钠盐的表面张力和临界胶束浓度有一定差异,但差别不大,其中氢化松香改性产物钠盐的表面活性最好,歧化松香改性产物钠盐的表面活性次之,去氢枞酸改性产物钠盐的表面活性最差.改性松香-缩合单宁酯钠盐对苯的乳化力都超过了60min,具有很好的乳化能力.改性松香-缩合单宁酯钠盐起泡比顺序为:氢化松香-黑荆树树皮缩合单宁酯钠盐>歧化松香-黑荆树树皮缩合单宁酯钠盐>去氢枞酸-黑荆树树皮缩合单宁酯钠盐>去氢枞酸-毛杨梅树皮缩合单宁酯钠盐>毛杨梅树皮缩合单宁钠盐. 相似文献
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油茶中茶皂素的膜分离-大孔树脂联用技术的研究 总被引:1,自引:0,他引:1
采用陶瓷膜与大孔树脂吸附技术联用分离纯化油茶饼粕提取液中的茶皂素。将油茶饼粕提取液先过陶瓷膜,以膜通量、油茶皂素转移率与除杂率为主要指标进行优化选择,再将陶瓷膜透过液进行大孔树脂吸附,以茶皂素的收率、纯度为考察指标进行工艺优化。结果表明:优化的纯化工艺为油茶饼粕提取液过0.05μm的陶瓷膜,料液质量分数为1%,操作压力为0.15 MPa;陶瓷膜透过液上AB-8大孔树脂柱,先以水洗至无色,再以0.2%NaOH溶液洗至流出液颜色较淡,水洗至中性,再以60%乙醇洗脱,60%乙醇部分为茶皂素部位,总茶皂素质量分数大于95%。采用膜分离-大孔树脂联用技术得到的茶皂素不仅纯度高、颜色淡,且该技术生产成本低,污染小,可以成为工业上生产茶皂素产品的一种新技术。 相似文献
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Preparation of strongly acidic cation-exchange resins from gymnosperm acid hydrolysis lignin 总被引:1,自引:0,他引:1
The chemical preparation of strongly acidic cation-exchange resin from sulfuric acid lignin (Klason lignin) (SAL), a typical acid hydrolysis lignin, was investigated. Sulfonation of resinified SAL itself gave a resin with an ion-exchange capacity of 2.3 mEq/g. After resinification with formaldehyde, the phenolized SAL with a reactivep-hydroxyphenyl group yielded a resin with an ion-exchange capacity of 3.2 mEq/g. The latter capacity is superior to that of the corresponding commercial phenol-type resins (2–3 mEq/g), but did not reach the level of the corresponding commercial styrene-type resins (4-5 mEq/g).This paper was presented at the 43th Lignin Symposium, Fuchu, October 1998 相似文献
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将黑荆树单宁与多聚甲醛在有机分散剂液体石蜡中发生反相悬浮聚合反应,制备出一种球状单宁螯合树脂,并通过正交试验得出适宜的合成条件为:单宁与多聚甲醛的质量比为12:1、反应温度67℃、反应时间3.5 h、石蜡体积65 mL.利用红外光谱、X射线衍射、热分析和扫描电镜等方法对单宁螯合树脂结构与性能变化进行深入研究;并初步探讨了单宁螯合树脂与Cr6 之间的作用机理. 相似文献
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红麸杨果实经纤维素酶处理后,采用体积分数70%乙醇-大孔吸附树脂联用技术对黄颜木素进行提取、纯化,以黄颜木素得率为考察指标,采用正交试验优化了酶辅助提取工艺,并从8种大孔吸附树脂中筛选出对黄颜木素分离纯化最佳的树脂,研究了该树脂对黄颜木素静态、动态吸附与解吸效果。结果表明:酶处理的最佳条件为酶用量120 U/mL,酶解温度55℃,酶解时间60 min,酶解pH值4.5,黄颜木素得率可达1.35%,纯度为14.59%。通过静态吸附试验筛选出最有效的XDA-8树脂用于黄颜木素的纯化,XDA-8分离纯化黄颜木素动态吸附试验的最佳条件为上样质量浓度14.4 g/L,流速80.384 mL/h,洗脱液乙醇体积分数为60%,洗脱液流速80.384 mL/h,解吸率为91.86%,纯化后黄颜木素纯度达到了68.15%。 相似文献
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Arabinogalactan (AG) obtained from Larix gmelinii R. waS purified with the method of macroporous resin adsorption. Effects of various parameters on the adsorption, including adsorption time and temperature, the concentration and the dosage of raw AG the reused numbers of resin, were investigated. The effect of purification was tested through the removal rate of impurity and the contents of AG and impurity. The optimal condition was determined as follows: adsorbed at 30℃ for 2 h with the concentration of raw AG 〈0.1 g·mL^-1 and its dosage 〈 7 mL, the dose of resin was 3 g and reused for 4 times. On the basis of these, macroporous resin column was used for AG purification. The result showed that the AG yield could reach 68.28% with sugar content of 95.02%. The analysis of IR and UV showed that the effect of macroporous resin characteristics on the purification of AG was significant. The obtained product had the same functional groups with standard sample. 相似文献
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基于开发和利用生物质竹炭材料,以竹炭粉、凹凸棒、硅藻土等为原料,制备竹炭陶瓷复合材料,从而避免传统炭吸附材料易碎和粉尘污染的缺点。首先,将原料通过陶瓷造粒工艺制备成直径为2~5 mm的小球;然后,在N 2气氛中1250℃下烧结为竹炭陶小球,并对其结构和吸附性能进行了研究。XRD测试结果表明,竹炭陶瓷复合材料在烧结前后并未改变竹炭陶晶体结构。原料的SEM测试结果表明,竹炭粉在微观结构上存在1μm左右的大孔,其中硅藻土的微观形貌为多孔圆盘状结构,圆盘的直径分布在20~50μm,孔道直径在0.1~1.2μm;竹炭陶的SEM测试结果表明,断面结构疏松多孔,经过复合和烧结后,仍然保持了原有的孔道结构,保障了竹炭陶的吸附性能。BET法测试结果表明,竹炭陶的比表面积达到118.54 m^2/g。吸附性能测试表明,竹炭陶对水分吸附率达到22.0%,对甲醛、氨气及硫化氢等有害气体的吸附率分别达到87.7%,94.6%和96.3%。实验结果表明,竹炭陶具有良好的吸湿和气体吸附性能,是一种良好的空气净化材料,在室内环境和水处理等方面具有广阔的应用前景。 相似文献
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大孔树脂对印楝素A吸附纯化的研究 总被引:3,自引:0,他引:3
通过比较5种大孔吸附树脂对印楝素A的吸附率和解吸率,成功地筛选出比较理想的树脂。研究结果表明:XAD-1180树脂对印楝素A有较好的吸附和解吸效果。并对其动态吸附、解吸性能进行了考察,发现较佳的吸附条件为:印楝素A质量浓度2.23 mg/mL(溶剂为30%甲醇-水溶液,以下同),流速1 BV/h,饱和吸附量4.5~5 BV;解吸条件为:以50%、60%、70%的甲醇-水溶液梯度洗脱。一次提纯产品的纯度为85.14%,经过二次提纯的纯度可达93.18%。纯化产物经HPLC-MS进一步确认为印楝素A。 相似文献
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Preparation of anion-exchange resins from pine sulfuric acid lignin,one of the acid hydrolysis lignins 总被引:4,自引:0,他引:4
To utilize acid hydrolysis lignin effectively, chemical conversion to anion-exchange resin was investigated by two methods. Sulfuric acid lignin (SAL) was selected as a typical acid hydrolysis lignin in this experiment. Because it is less reactive, SAL was phenolated with sulfuric acid catalyst to yield reactive phenolized SAL (P-SAL) with p-hydroxyphenyl nuclei. One method was the restricted resinification of P-SAL followed by the Mannich reaction with formaldehyde and dimethylamine to yield a weakly basic anion-exchange resin with an ion-exchange capacity of 2.4mEq/g. Another method was to react resinified P-SAL with glycidyltrimethylammonium chloride to yield a strongly basic anion-exchange resin with an ion-exchange capacity of 2.0mEq/g. The reaction of a simple P-SAL model compound with an epoxide suggested that the phenolic hydroxyl group of the p-hydroxyphenyl nucleus had slightly higher reactivity than that of the guaiacyl nucleus.Part of this report was presented at the 47th Lignin Symposium, Fukuoka, October 2002 相似文献