【作者】 宋玉梅；

【导师】 张淑芬；

【作者基本信息】 大连理工大学 ， 化学工程与技术， 2012， 硕士

【摘要】 秸秆全利用是高附加值利用秸秆的一条简便宜行的技术路线。本文选择玉米秸秆为原料,对其进行化学改性制备阳离子秸秆,目的是使秸秆中组分全利用,并研究全利用阳离子秸秆吸附材料对水溶液中三种酸性染料的吸附性能,以此评价阳离子秸秆的应用性能,为秸秆高附加值的全利用提供一条可行的路线。论文主要研究内容及结果如下：本文首先研究了秸秆的性质和结构,测定了玉米秸秆中纤维素、半纤维素和木质素的组分含量,分别为32%、26%和18%；研究了室温下秸秆在溶剂中的溶解性能,发现秸秆在1%氢氧化钠溶液中溶解度为0.26g；秸秆的SEM图片表明秸秆本身具有孔道结构,适于做吸附材料。本文以玉米秸秆为原料,GTA作阳离子化试剂,直接阳离子化合成了阳离子秸秆。研究了碱化时间、反应温度、碱用量、反应时间、阳离子化试剂用量对秸秆利用率、GTA的利用率和阳离子基团含量的影响。结果表明秸秆阳离子化改性的较佳工艺条件是：反应时间3h,反应温度70°C, GTA用量为3mol/kg秸秆,n(NaOH):n(GTA)=1.5:1, GTA利用率为53.2%,秸秆阳离子基团含量为1.60mmol/g,秸秆利用率达到80%。使用元素分析和红外光谱分析方法,对改性前后玉米秸秆的组成元素和结构进行了表征证实阳离子基团的引入。以玉米秸秆为原料,DMF作溶剂,环氧氯丙烷作交联剂,GTA作阳离子化试剂,合成了阳离子秸秆。研究了反应温度、碱用量、反应时间、阳离子化试剂用量对秸秆利用率、GTA的利用率和阳离子基团含量的影响。结果表明秸秆阳离子化改性的较佳工艺条件是：反应时间4h,反应温度90°C, n(NaOH):n(GTA)=1:l.GTA用量为3mol/kg秸秆。此时,GTA利用率为51.2%,秸秆接枝率为1.53mmolGTA/g秸秆,秸秆利用率达到95%。使用元素分析和红外光谱分析方法,对改性前后玉米秸秆的组成元素和结构进行了表征证实阳离子基团的引入。以全利用阳离子秸秆作为染料废水中酸性红1、酸性黄128和酸性黄199三种酸性染料的吸附剂,研究了阳离子秸秆投加量、pH值、吸附时间和氯化钠浓度等因素对吸附效果的影响,结果表明,对于浓度0.1g/L的染料废液,在阳离子秸秆投加量对三种染料废液的投加量分别为1.1g/L、0.9g/L、1.0g/L,pH值6,吸附时间4h的条件下,染料废水脱色率均可达到99.9%。利用浓度为1mol/L的NaOH溶液对吸附剂进行解吸,并循环利用,当循环次数达到5次时,脱色率降至65%。更多还原

【Abstract】 Full use of stalk is a simple and low-cost technology to prepare high-value stalk derivatives. So the cationic stalk was prepared to realize the full use of com stalk and applied to remove anionic dyes from aqueous solution to evaluate the application properties and provide a feasible technology route high-value utilization of stalk.In this study, the stalk properties and structure were studied firstly. The cellulose, hemicellulose and lignin components in grains in com stalk were measured and the result was32%,26%and18%respectively. The solubility property of the com stalk was studied and its solubility in NaOH(l%) solution was0.26g. The stalk SEM images were observed, which showed that the stalk itself had pore structure and it was good absorption material.Cationic absorbent was prepared by using corn stalk as raw materials, GTA as cationic agent. The optimal synthesis condition was got:reaction time was3h, reaction temperature was70°C, GTA dose was3mol/kg stalk and NaOH dose was n(NaOH):n(GTA)=1.5:1. GTA utilization rate was53.2%, cationic group content was1.60mmol/g and the utilization rate of stalk was80%. The introduction of cationic groups was confirmed by elemental analysis and IR spectroscopy.Cationic absorbent was prepared by using corn stalk as raw materials,3-chloro-l,2-epoxypropane as crosslinking agent and GTA as cationic agent. The optimal synthesis condition was got:reaction time was4h, reaction temperature was90°C, GTA dose was3mol/kg stalk and NaOH dose was n(NaOH):n(GTA)=1:1. GTA utilization rate was51.2%, cationic group content was1.53mmol/g, and the utilization rate of stalk was95%. The introduction of cationic groups was confirmed by elemental analysis and IR spectroscopy.The cationic absorbent was applied to remove anionic dyes such as AR1, AY128and AY199from aqueous solution and the effects of adsorbent dosage, pH, time and NaCl concentration on decolorization rate were studied. The optimal absorption conditions were: when the concentrations of the there dyes above were0.1g/L, cationic straw dosage of three dyes were1.1g/L,0.9g/L,1.0g/L respectively, pH value was6and the adsorption time was4h. Under these conditions,the dye decolorization rates all reached99.9%. NaOH solution (1.0mol/L) was applied to desorb the absorbent. When the absorption-desorption was repeated5times, the removal rate of AR1waste solution(0.1g/L) droped to65%.更多还原