【作者】 卢璐；

【导师】 柯勤飞；

【作者基本信息】 东华大学 ， 纺织工程， 2011， 硕士

【摘要】 Cu2+广泛存在于电镀厂、线路板厂、印染厂等工业的废水中,对农作物污染严重。Cu2+是重金属离子,能使蛋白质变性失去活性,人一旦过量摄取,会发生恶心、呕吐、急性溶血等中毒现象,因此净化工业废水中的Cu2+势在必行。常用的除去的方法有化学沉淀法、离子交换法、电解法、重金属螯合剂法等,但是成本较高。而生物吸附材料成本低、效果好,近年来受到广泛关注。在我国,羽毛作为一种廉价的自然资源,多数作为废弃物。已经有研究发现羽毛中的角蛋白具有高活性基团、形态复杂等特点,对Cu2+有较好的吸附作用,但是吸附机理尚不明确。因此,研究羽毛过滤材料对Cu2+的吸附机理,为羽毛在净化含Cu2+废水的应用上奠定理论基础,对节约资源、环境保护意义重大。本课题主要采用光谱法研究羽毛对CuSO4溶液中Cu2+的吸附机理。首先采用测量吸光度的方法测得羽毛纤维对Cu2+的吸附量,用电子顺磁共振、红外光谱、广角X衍射分析吸附前后羽毛纤维内部结构的变化。然后用酸、碱、超声波分别对羽毛改性,设法提高羽毛的吸附性能。接着用红外光谱和广角X衍射分析改性引起的羽毛结构变化,进一步推断Cu2+的吸附机理。再通过吸附-解吸附的反复实验,检验羽毛用于Cu2+吸附的可循环利用性。结果发现未改性羽毛纤维有一定的吸附Cu2+的能力但是不高。Cu(Ⅱ)在羽毛纤维中主要有3种配位结构,其中一种以S原子为主,成共价键配位；另两种以N原子为主,共价键和离子键共存。β折叠结晶结构上的胱氨酸可能与Cu(Ⅱ)形成了配位结构。吸附Cu2+后,羽毛蛋白中出现了更多的α螺旋构型,而β折叠构型相对减少。对于改性1小时的羽毛,NaOH改性羽毛的吸附性能最佳,1小时的改性使β折叠结晶结构和α螺旋结晶结构都被破坏,共同发生吸附作用。NaOH改性时间延长到一定程度时,主要发生β折叠结晶结构向α螺旋结晶结构的转化作用,α螺旋结晶结构的吸附能力可能超过β折叠结晶结构。反复的吸附-解吸附使吸附点增多,吸附能力提高。在实际应用中,由于羽毛纤维易飘散,因此一般制成非织造羽毛毡后再使用,本课题将羽毛和ES纤维制作成羽毛毡,用碱改性,比较不同ES纤维含量的毡吸附Cu2+的能力。由于印刷电路板的废水中,Cr(VI)和Cu2+为主要污染物,因此本课题还探讨羽毛毡对Cu2+的吸附能力与初始溶液中添加的Cr的含量的关系。结果表明只要羽毛纤维的含量相同,ES纤维所占比例对NaOH改性羽毛毡的吸附性能影响不大。未改性羽毛毡的Cu2+吸附量明显小于改性羽毛毡的。羽毛毡的吸附性能与羽毛纤维原料差别不大。随着初始CuSO4溶液中Cr的加入量增多,NaOH改性羽毛毡对Cu的吸附量逐渐减少,对Cr的吸附量随之增多。本课题的创新点是使用EPR分析吸附Cu2+后羽毛的化学结构以及检验羽毛的可循环利用性。更多还原

【Abstract】 Cu2+ is widespread in the industrial effluent such as Electroplating factory, circuit board factory, printing and dyeing mill, which pollute crops severely. Cu2+, a kind of heavy ions,can make proteins lose activity. Those who take in it excessively may exhibit poisoned phenomena like nausea, vomiting, acute hemolysis.Therefore, it is imperative to purify Cu2+ in the industrial effluent.The average methods are chemical sedimentation, ion exchange, electrolyzation, metal chelation and so on.However,the cost is too much. By contrast, biological absorption materials,which cost low with good effect, are widespreadly concerned in recent years.In our country,feahers, a kind of cheap natural resources, are mainly treated as waste.There have been studied that feather keratin,with high-activity groups and the complex shapes,is a very good adsorption to Cu2+, but the uptake mechanism is not explicit.Therefore, the research of Cu2+ uptake mechanism by feather liquid filtered material in industrial waste water,is in favor of providing theoretical basis for purifying industrial effluent with Cu2+ and is significant for resources economy and environmental protection.This topic mainly studies the Cu2+ uptake mechanism of feathers in CUSO4 solution by Spectroscopy.First,test the Cu2+ uptake amount of feathers by measuring absorbancy and analyse the inner structure change of feathers before and after Cu2+ absorption by EPR、FT-IR、XRD.Next,modify feathers by acid、alkali and ultrasonic respectively to improve the absorptive ability of feathers.And then,analyse the inner structure change of feathers due to modification by FT-IR、XRD,in order to further deduce the the Cu2+ uptake mechanism.Next test the cyclic utilization of feathers’Cu2+ absorption by repeating absorption and desorption. After research,I find that the non-modified feather fibers immersed into CUSO4 solution have the Cu2+ absorption ability but not strong. Cu(Ⅱ) exist in feather with 3 coordinating structure.One of them is main S, coordinated in covalent bonds,another two mainly coordinate with N atoms and the covalent bonds exist as well as electrovalent bonds.After absorbing Cu2+,αhelical structures increase butβsheet structures decrease.After one hour’s modification with acid、alkali and ultrasonic respectively,the uptake ability of NaOH modified feathers is best. To them,both a helical structures andβsheet structures are destroyed and take part in absortption.When feathers are modified with NaOH extending to a certain time,the main reaction is the change of (3 sheet structures to a helical structures.Maybe a helical structures are more absorptive thanβsheet structures Repeating absorption and desorption increase the absorption sites and the absorption ability.In practical applications, feather fibers are easy to disperse,so it is usually using feather nonwoven material.In this topic,feather mixed with ES are made into nonwovens,modified with NaOH,to compare the Cu2+ absorption ability of feather nonwovens with different ES contents.Because in printed circuit board factory waste water,Cr(VI) and Cu2+ are main pollution,so this topic also research the relationship between Cu2+ uptake ability of feather nonwovens and initial Cr contents.The results show that as long as the content of feather fibers are equal,the proportion of ES fibers does not affect NaOH modified felt very much.Non-modified felt has less Cu2+ absorption ablity than modified felt.The absorption ablity difference of feather fibers and feather felt is not much. As the initial Cr content increases,NaOH modified feather felt absorbs less Cu but more Cr.This topic’s innovation is analysing feathers’structure by EPR after Cu2+ absorption and test the cyclic utilization of feathers.更多还原