本文選題：蠶絲絲膠 + 柿單寧��； 參考：《西安建筑科技大學(xué)》2016年碩士論文

【摘要】：生物吸附法因效率高,成本低,不產(chǎn)生二次污染等優(yōu)點,在貴金屬回收研究中日漸受到青睞。本文分別以絲膠(SS)和柿皮粉(PP)為原料,通過接枝官能團制備了改性生物吸附劑2,5-二硫二脲改性絲膠(BTU-SS)和2,5-二巰基噻二唑改性柿皮(DMTD-PP),并采用紅外光譜、Zeta電位、元素分析等分析手段對生物吸附劑進行了表征。實驗對比研究了改性前后生物吸附劑對貴金屬酸浸液中Au(Ⅲ)和Ag(Ⅰ)的吸附行為,并通過靜態(tài)實驗考察了吸附時間、吸附劑投加量、p H值、溫度等因素對吸附行為的影響,吸附劑的再生利用性能及其在多組分體系中對Au(Ⅲ)和Ag(Ⅰ)的選擇性吸附性能,通過動態(tài)吸附實驗研究了生物吸附劑從五組分酸浸液中選擇性分離Au(Ⅲ)和Ag(Ⅰ)的可能性,并對吸附動力學(xué)和熱力學(xué)進行了分析,對生物吸附機理也進行了初步探討。主要結(jié)果如下:(1)在p H1.0-6.0范圍,BTU-SS和SS對Ag(Ⅰ)吸附率隨著p H升高而增大。在單組分Ag(Ⅰ)溶液中,p H5.0時,BTU-SS和SS對Ag(Ⅰ)的平衡吸附率分別為98.3%和58.5%,吸附容量分別為30.3 mg?g-1和18.0 mg?g-1。在Ag(Ⅰ)-Cu(Ⅱ)-Zn(Ⅱ)及Ag(Ⅰ)-Cu(Ⅱ)-Zn(Ⅱ)-Ni(Ⅱ)-Pb(Ⅱ)溶液中,p H5.0時,BTU-SS對Ag(Ⅰ)的吸附率分別高達96.9%和94.0%,而對其它賤金屬離子則很少吸附,顯示出對Ag(Ⅰ)良好的吸附選擇性。SS盡管對其它賤金屬離子吸附率也較低,但在上述兩種溶液中,SS對Ag(Ⅰ)的吸附率僅為38.7%和32.0%。吸附動力學(xué)表明,吸附劑對Ag(Ⅰ)的吸附符合準二級動力學(xué)模型,吸附過程為化學(xué)吸附,吸附過程活化能Ea(BTU-SS)=47.67 k J?mol-1,Ea(SS)=53.27 k J?mol-1。吸附熱力學(xué)表明吸附過程為放熱的自發(fā)過程。25℃吸附平衡時,Ag(Ⅰ)在固液兩相的分配系數(shù)為ΘDK(BTU-SS)=16634.6,ΘDK(SS)=403.3。(2)25℃,p H3.0時,PP和DMTD-PP對Au(Ⅲ)的吸附率分別為37.3%和98.2%,吸附容量分別為11.9 mg?g-1和31.4 mg?g-1。DMTD-PP可高效選擇吸附Au(Ⅲ)-Cu(Ⅱ)-Zn(Ⅱ)-Ni(Ⅱ)-Pb(Ⅱ)酸浸液中的Au(Ⅲ),p H3.0時,Au(Ⅲ)的吸附率為97.7%,而對其它賤金屬離子吸附率均不足5%。DMTD-PP對Au(Ⅲ)的吸附符合準二級動力學(xué)模型,吸附過程為化學(xué)吸附,吸附過程活化能Ea(DMTD-PP)=101.1 k J?mol-1。吸附熱力學(xué)表明吸附過程為吸熱的自發(fā)過程。25℃吸附平衡時,Au(Ⅲ)在固液兩相的分配系數(shù)為ΘDK( DMTD-PP)= 17580.9。(3)動態(tài)吸附實驗表明,BTU-SS和DMTD-PP對Ag(Ⅰ)和Au(Ⅲ)具有較強的親合力。BTU-SS吸附Ag(Ⅰ)在130 B.V.(13 h)發(fā)生穿透,250 B.V.(25 h)達到飽和,而Ag(Ⅰ)以外的賤金屬離子迅速到達穿透點。硝酸-硫脲混合液洗脫2 h,Ag(Ⅰ)的濃縮因子為4.9,8 h內(nèi)解吸率達92.2%;DMTD-PP吸附Au(Ⅲ)在255.6 B.V.(23h)發(fā)生穿透,444.4 B.V.(40 h)達到飽和,鹽酸-硫脲混合液洗脫2 h,Au(Ⅲ)的濃縮因子為10.22,10 h內(nèi)解吸率達93.4%。因此,以BTU-SS和DMTD-PP作為吸附劑,通過吸附柱可實現(xiàn)Au(Ⅲ)和Ag(Ⅰ)的選擇性富集以及吸附劑的再生利用。(4)生物吸附劑BTU-SS和DMTD-PP對Ag(Ⅰ)和Au(Ⅲ)的吸附機理主要表現(xiàn)為離子交換、靜電作用和配位作用,粒子內(nèi)擴散為吸附過程的速控步驟。
[Abstract]:The biological adsorption method with high efficiency, low cost, does not have two pollution and other advantages, in the study of recovering precious metals is increasingly favored. In this paper, the sericin (SS) and persimmon peel powder (PP) as raw materials, was prepared by grafting functional groups of modified biosorbent 2,5- two sulphur urea modified sericin (two BTU-SS and 2,5- two) two triazole modified mercapto thiadiazole persimmon peel (DMTD-PP), and the use of infrared spectroscopy, Zeta potential of biological adsorbent were characterized by elemental analysis and other analysis methods. Experimental study of modified adsorbent for noble metal acid leaching solution of Au (III) and Ag (I). Adsorption behavior and adsorption time were investigated through static experiments, adsorbent dosage, P value of H, temperature and other factors on the adsorption behavior, adsorption properties and recycling in the multicomponent system of Au (III) and Ag (I) the selective adsorption performance by dynamic adsorption experiment the biological 鍚擱檮鍓備粠浜旂粍鍒嗛吀嫻告恫涓，

本文編號：1772461