【摘要】：近年來隨著我國治理大氣污染的形勢(shì)日趨嚴(yán)峻,對(duì)清潔能源的需求已十分迫切,作為清潔能源的一種,核電的大規(guī)模建設(shè)已漸漸開展,數(shù)量眾多的核電站在為國民經(jīng)濟(jì)提供動(dòng)力的同時(shí),也需消耗大量鈾燃料。這對(duì)鈾礦開采和鈾燃料生產(chǎn)提出了更高的要求,開展鈾污染防治研究,尤其是鈾廢水處理研究也已迫在眉睫。 在眾多重金屬廢水處理方法中,吸附法是一種成本低廉、操作簡便、效果良好的方法。天然高分子吸附材料殼聚糖富含活性基團(tuán)羥基和氨基,對(duì)多種重金屬具有較強(qiáng)的吸附效果,但其可溶解于弱酸性水體,物理機(jī)械強(qiáng)度較弱,對(duì)鈾的選擇吸附性能一般,限制了其在鈾廢水處理方面的應(yīng)用。殼聚糖與冠醚接枝可改進(jìn)殼聚糖的選擇吸附性,提高其不溶解性。胺肟基具有生物相容性,對(duì)鈾的選擇吸附性較好,胺肟化聚丙烯腈殼聚糖可同時(shí)改善殼聚糖的物理性質(zhì)與選擇吸附性。 響應(yīng)面分析方法是一種多因素分析方法,在多種工業(yè)領(lǐng)域已被廣泛應(yīng)用與認(rèn)可,將其運(yùn)用于鈾吸附研究,可分析多因素相互作用對(duì)于因變量的影響,優(yōu)化得到最佳實(shí)驗(yàn)因素值,這是常規(guī)的單因素方法所不具備的,其分析結(jié)果直觀而全面。 本文通過接枝反應(yīng),成功合成了苯并-15-冠醚-5接枝殼聚糖(CTCE):通過接枝共聚與胺肟化反應(yīng),成功合成了胺肟化聚丙烯腈接枝殼聚糖(CTS-g-PAO)。對(duì)于兩種材料,通過響應(yīng)面分析方法準(zhǔn)確擬合了溶液初始pH值、鈾濃度和固液比對(duì)鈾(Ⅵ)吸附量與吸附率的影響(模型p-value均小于0.01,達(dá)到極顯著水平)。研究結(jié)果表明兩種材料均在弱酸性條件下(pH值約為6.0～7.0)取得了較好的吸附效果,CTCE和CTS-g-PAO對(duì)鈾的最佳吸附量和吸附率分別為234.26mg/L、79.92%和312.06mg/g、86.02%。 動(dòng)力學(xué)與熱力學(xué)分析表明CTCE和CTS-g-PAO對(duì)鈾的吸附過程都更符合準(zhǔn)二級(jí)吸附動(dòng)力學(xué)模型和Langmuir等溫吸附模型。結(jié)合FTIR分析結(jié)果,CTCE和CTS-g-PAO對(duì)鈾的吸附過程應(yīng)為螯合反應(yīng)。CTS-g-PAO經(jīng)三次吸附洗脫仍保持80%以上的吸附量,CTS-g-PAO比普通殼聚糖具有更好的選擇吸附性與物理特性。以上結(jié)果表明CTS-g-PAO具有良好的實(shí)際應(yīng)用前景。
[Abstract]:In recent years, with the increasingly serious situation of controlling air pollution in China, the demand for clean energy has become very urgent. As a kind of clean energy, the large-scale construction of nuclear power has been gradually carried out. A large number of nuclear power plants, while providing power to the national economy, also need to consume a large amount of uranium fuel. This puts forward higher requirements for uranium mining and uranium fuel production, and it is urgent to carry out research on uranium pollution prevention and control, especially on the treatment of uranium wastewater. Among many heavy metal wastewater treatment methods, adsorption method is a cheap, simple and effective method. Chitosan, a natural polymer adsorption material, is rich in active groups of hydroxyl groups and amino groups, and has a strong adsorption effect on many heavy metals, but it can be dissolved in weak acid water, and its physical and mechanical strength is weak. Its application in uranium wastewater treatment is limited. Graft copolymerization of chitosan with crown ether can improve the selectivity and insolubility of chitosan. The amoxime group has biocompatibility and good selective adsorption of uranium. The amoxime polyacrylonitrile chitosan can improve the physical properties and selective adsorption of chitosan simultaneously. Response surface analysis (RSM) is a multi-factor analysis method, which has been widely used and recognized in many industrial fields. It can be applied to the study of uranium adsorption. The effect of multi-factor interaction on dependent variables can be analyzed, and the optimum experimental factors can be obtained. This is not available in the conventional single-factor method, and the results are intuitive and comprehensive. In this paper, the graft copolymerization of benzo-15-crown-ether-5 chitosan (CTCE):) with amine oximation was carried out successfully, and the acrylonitrile grafted chitosan (CTS-g-PAO) was successfully synthesized by graft copolymerization of benzo-15-crown-ether-5 chitosan. For the two materials, the effects of the initial pH value, the concentration of uranium and the ratio of solid to liquid on the adsorption capacity and adsorption rate of uranium (鈪，

本文編號(hào)：2311090