【摘要】：聚氯乙烯(PVC)樹脂是世界五大工程塑料之一,在各行各業(yè)有著非常廣泛的應(yīng)用。目前氯乙烯單體的工業(yè)合成方法主要有乙烯法和乙炔法。發(fā)達(dá)國家多采用石油化工資源的乙烯法,但因?yàn)槲覈厥獾摹案幻�、貧油、少氣”的能源結(jié)構(gòu)和乙烯原料匱乏,決定了占據(jù)我國合成氯乙烯工藝路線主導(dǎo)地位的是乙炔氫氯化法。在電石法氯乙烯生產(chǎn)中,氯化汞催化劑由于其催化活性與選擇性都比較理想而成為廣泛應(yīng)用的催化劑。但是,氯化汞催化劑的升華、流失為人類和環(huán)境所帶來的毒性與污染成為長期困擾電石法PVC工藝路線的問題。為實(shí)現(xiàn)電石法PVC工藝路線的可持續(xù)發(fā)展,必須開發(fā)環(huán)境友好的、高性能的、能替代汞系催化劑的新型無汞催化劑。本文主要從載體改性對(duì)乙炔氫氯化反應(yīng)中Ru基催化劑活性組分和Ru顆粒大小的影響方面來探討。主要研究內(nèi)容為以下三個(gè)方面:(1)合成3D復(fù)合碳氮材料(g-C_3N_4 NS-CNT)載體負(fù)載RuCl3制備Ru/g-C_3N_4 NS-CNT催化劑,N2-吸附脫附曲線(BET)表明了g-C_3N_4 NS-CNT材料的多孔結(jié)構(gòu),這可以提供大量的活性位,X射線衍射(XRD)說明g-C_3N_4 NSs和CNTs的特征峰被完好保存在3D g-C_3N_4 NS-CNT復(fù)合材料中,XPS證明了它們之間的強(qiáng)耦合作用�；钚詼y試可知,復(fù)合材料載體負(fù)載的Ru基催化劑的催化活性有一定程度的提高。(2)對(duì)活性炭表面進(jìn)行一步和兩步液相氧化法的改性,用沉淀-浸漬法和還原法制備Ru基催化劑。由活性測試可知,兩步液相法制備的Ru基催化劑的初始活性要比一步法的高,由TEM和CO-TPD表征解釋原因?yàn)?用兩步氧化法處理后的載體會(huì)使Ru基催化劑產(chǎn)生更小粒徑的均一Ru顆粒。(3)對(duì)活性炭(AC)表面進(jìn)行-NO2,-NH2和-NHN氮官能團(tuán)的改性,以AC和改性后的活性炭為載體,RuCl3為活性組分,通過等體積浸漬法制備Ru基催化劑。用傅立葉紅外光譜(FT-IR)、N2-吸附脫附曲線(BET)和元素分析來驗(yàn)證氮官能團(tuán)的引入,用X射線光電子能譜分析(XPS)和分峰軟件來說明不同Ru物種的變化,用程序升溫脫附(TPD)來觀察對(duì)HCl和C2H3Cl的吸附情況。經(jīng)過活性測試可知,改性載體負(fù)載的Ru基催化劑相對(duì)于未改性負(fù)載的催化劑,活性有大幅度提高,主要的原因歸于RuO2活性組分的增加和HCl吸附的增強(qiáng)。
[Abstract]:PVC (polyvinyl chloride) resin is one of the five major engineering plastics in the world, and has a very wide application in all walks of life. At present, the industrial synthesis of vinyl chloride monomer is mainly ethylene and acetylene. In the developed countries, the ethylene method of petrochemical resources is used, but because of the energy structure and the shortage of the ethylene raw materials of the special "rich coal, lean oil and less gas" in China, the acetylene hydrochlorination process is determined to occupy the leading role of the synthetic vinyl chloride process in China. In that production of chloroethylene by the calcium carbide method, the mercuric chloride catalyst is a widely used catalyst because of the ideal catalytic activity and selectivity. However, the sublimation of the mercuric chloride catalyst and the loss of the toxicity and the pollution caused by the human and the environment have become a long-term problem of the process route of the calcium carbide method PVC. In order to realize the sustainable development of the PVC process route of the calcium carbide method, an environment-friendly, high-performance, mercury-free catalyst capable of replacing the mercury-based catalyst must be developed. In this paper, the effect of carrier modification on the active component of Ru-based catalyst and the size of Ru particles in the chlorination of acetylene is discussed. The main contents of the study are as follows: (1) The preparation of Ru/ g-C _ 3N _ 4NS-CNT catalyst by synthesis of a 3D composite carbon-nitrogen material (g-C _ 3N _ 4NS-CNT) carrier and the N2-adsorption desorption curve (BET) show the porous structure of the g-C _ 3N _ 4NS-CNT material, which can provide a large number of active sites, X-ray diffraction (XRD) shows that the characteristic peaks of g-C _ 3N _ 4 NSs and CNTs are well preserved in the 3D-g-C _ 3N _ 4NS-CNT composite, and the XPS shows the strong coupling between them. The activity test shows that the catalytic activity of the Ru-based catalyst supported by the composite carrier is improved to some extent. (2) the surface of the activated carbon is modified by one-step and two-step liquid-phase oxidation, and the Ru-based catalyst is prepared by a precipitation-impregnation method and a reduction method. As can be seen from the activity test, the initial activity of the Ru-based catalyst prepared by the two-step liquid phase method is higher than that of the one-step method, and the reason of the explanation by the TEM and the CO-TPD is that the Ru-based catalyst can generate uniform Ru particles with smaller particle size by the Ru-based catalyst after the two-step oxidation process is used. And (3) modifying the surface of the active carbon (AC)-NO2,-NH2 and-NHN nitrogen, taking AC and modified active carbon as a carrier, and RuCl3 as an active component, and preparing a Ru-based catalyst by equal volume impregnation. The introduction of nitrogen functional groups was verified by FT-IR, N2-adsorption and desorption curves (BET) and elemental analysis, and the changes of different Ru species were described by X-ray photoelectron spectroscopy (XPS) and peak-splitting software. The adsorption of HCl and C2H3Cl was observed by temperature-programmed desorption (TPD). The activity test shows that the activity of the supported Ru-based catalyst is greatly improved compared with the non-modified supported catalyst, and the main reason is attributed to the increase of the RuO2 active component and the enhancement of the adsorption of HCl.
【學(xué)位授予單位】：石河子大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2016
【分類號(hào)】：O643.36;TQ222.423
，

本文編號(hào)：2444802