电气石催化过硫酸盐降解染料废水

发布时间：2018-05-04 13:34

  本文选题：电气石 + 直接红23　； 参考：《吉林大学》2016年硕士论文

【摘要】：染料废水的大量排放造成了严重的水污染现象,威胁环境与人类的安全,其中偶氮染料是应用较为广泛的染料。偶氮染料废水由于化学需氧量较高、较难降解等特点是目前染料废水降解研究的重点。电气石作为一种对环境非常有利的矿物质被广泛应用于污染物的去除,常见的利用电气石去除污染物的方法主要有吸附法和高级氧化工艺。电气石的pHZPC为6.17,表面呈多孔结构,在酸性条件下能够析出Fe2+和Fe3+,该性质为电气石作为高级氧化工艺的催化剂提供了可能。本文中所使用的电气石经XPS分析可知,Fe(II)与Fe(III)的比例为50.47%:49.53%。通过对电气石粉末的XRD分析可知,电气石的晶体结构式为NaFe3Al6[Si6O18][BO3]3(OH)4。通过对TM(电气石)、(过硫酸盐)PS、PS/US(过硫酸盐/超声)、TM/PS(电气石/过硫酸盐)、TM/PS/US-10min(电气石/过硫酸盐/超声-10min)各系统的动力学研究,发现染料废水的氧化降解过程属于二阶动力学反应。超声能够促进染料废水的降解,其降解率能够高达92%。对比不同催化剂在无超声和有超声条件下催化过硫酸盐降解直接红23的研究发现,电气石由于其高去除率以及廉价易得的特性相较于其他催化剂更有优势。同时,研究通过测定反应过程中各催化剂系统中的Fe2+的含量,发现Fe2+的含量与催化剂对染料废水的处理效果具有一致性。TM/PS和TM/PS/US-10min系统分别对三种不同性质的偶氮染料进行降解,研究发现电气石催化氧化法对不同性质的染料废水具有适用性。不同无机盐离子对高级氧化工艺降解直接红23的影响,发现各无机盐离子对反应的影响程度为NaClO4≈NaNO3Na2SO4NaClNa2HPO4,由此可见Na2HPO4离子强度对反应的影响最大,经分析可知HPO42-能够消耗反应系统中的SO4-·的量。超声时间和超声功率能够影响电气石催化氧化降解直接红23的效果。电气石催化过硫酸盐降解直接红23不仅能够对染料废水进行脱色,同时能够有效的降低染料废水的COD和真色色度(ADMI),研究表明系统对三种偶氮染料废水的COD的去除率都高于90%以上。通过研究直接红23降解过程中波长扫描图发现,在波长为504nm和310nm处的吸收峰逐渐由陡到缓,峰高逐渐变低,这是由于位于504nm代表偶氮染料的-N=N-键遭到破坏,位于310nm处的与-N=N-相连的苯环被破坏。电气石样品的重复利用实验充分显示电气石在氧化实验中的可重复利用性。每一次经重复利用后,电气石催化过硫酸盐降解DR23的效果就有所降低,当重复利用四次后其降解率为43%。
[Abstract]:The discharge of dye wastewater causes serious water pollution and threatens the environment and human safety. Azo dyes are widely used. The degradation of azo dye wastewater is very important because of its high oxygen demand and difficult degradation. Tourmaline is widely used in the removal of pollutants as a mineral which is very beneficial to the environment. The common methods of removing pollutants by tourmaline are adsorption and advanced oxidation process. The pHZPC of tourmaline is 6.17, the surface of tourmaline is porous, and Fe2 and Fe3 can be precipitated under acidic conditions. This property makes it possible for tourmaline to be used as catalyst for advanced oxidation process. The XPS analysis of tourmaline used in this paper shows that the ratio of Fe (II) to Fe (II) is 50.47: 49.53. The XRD analysis of tourmaline powder shows that the crystal structure formula of tourmaline is NaFe3Al6 [Si6O18] [BO3] 3OHH4. The kinetics of TMS-PS-10min (tourmaline / persulfate / PS-10min) system is studied. It is found that the degradation process of dye wastewater is a second-order kinetic reaction. Ultrasound can promote the degradation of dye wastewater, and the degradation rate can be as high as 92%. Compared with the results of catalytic degradation of direct red 23 with persulfate without ultrasound and with ultrasound, it is found that tourmaline is superior to other catalysts because of its high removal rate and low cost. At the same time, through the determination of Fe2 content in each catalyst system during the reaction, it was found that the content of Fe2 was consistent with the treatment effect of the catalyst on dye wastewater. TMP / PS and TM/PS/US-10min system respectively degraded three kinds of azo dyes with different properties. It is found that tourmaline catalytic oxidation is suitable for dye wastewater with different properties. The effect of different inorganic salt ions on the degradation of direct red 23 was found to be NaClO4 鈮，

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