發(fā)布時(shí)間：2018-05-22 17:51

  本文選題：超臨界水熱合成 + 煤矸石　； 參考：《太原理工大學(xué)》2015年碩士論文

【摘要】：煤矸石是與煤共生的一種較為堅(jiān)硬、含有少量碳的黑色巖石，是我國(guó)目前堆存量最多的工業(yè)固體廢物之一。大量的煤矸石占用了耕地，且嚴(yán)重污染了自然環(huán)境。目前，煤矸石主要用于制造磚、水泥與其它建筑產(chǎn)品或提取化工產(chǎn)品，但存在利用率均不高及產(chǎn)品附加值低的缺點(diǎn)。煤矸石含有大量的高嶺石成分。高嶺石是層狀硅酸鹽粘土礦物，是合成沸石分子篩的理想原料之一。沸石分子篩具有離子交換性能、吸附分離性能及催化性能，在環(huán)境保護(hù)、石油化工、化學(xué)工業(yè)等領(lǐng)域有著很廣泛的應(yīng)用。利用煤矸石合成沸石分子篩可充分提高煤矸石利用率，產(chǎn)品的經(jīng)濟(jì)附加值也很高。目前礦物原料合成沸石分子篩的主要方法有水熱合成法、堿溶法、堿熔-水熱法、微波合成法和蒸汽相合成法，但以上合成方法操作過(guò)程復(fù)雜繁瑣，合成時(shí)間長(zhǎng)。超臨界水熱法具有許多獨(dú)特的性能：反應(yīng)在均相的環(huán)境中進(jìn)行、易于溶入多孔的物質(zhì)中、化學(xué)反應(yīng)速率高。采用超臨界水熱法合成類沸石分子篩可簡(jiǎn)化合成過(guò)程、極大地縮短反應(yīng)時(shí)間。本文基于超臨水的獨(dú)特性質(zhì)，以天然礦物原料高嶺石和煤矸石為原料，使用超臨界水熱法合成類沸石。考察堿溶液類型、堿溶液濃度、超臨界反應(yīng)時(shí)間和溫度對(duì)類沸石合成的影響。采用X射線衍射（XRD）、掃描電子顯微鏡（SEM）、熱重分析（TG-DTG）與傅里葉變換紅外光譜（FT-IR）等分析手段，對(duì)產(chǎn)物進(jìn)行測(cè)定表征。并通過(guò)脫除廢水中汞離子的效率來(lái)考察合成的類沸石材料的吸附性能。實(shí)驗(yàn)結(jié)果表明： （1）反應(yīng)溫度為400℃時(shí)，高嶺石與1mol/L碳酸鈉溶液、1mol/L氫氧化鈉溶液與2mol/L氫氧化鉀溶液在超臨界水熱條件下，，分別成功合成了方鈉石、鈣霞石與鉀霞石這些類沸石材料，產(chǎn)物結(jié)晶度很高，粒徑分布較均勻。合成類沸石最佳反應(yīng)時(shí)間都為5min，和傳統(tǒng)水熱合成法相比，反應(yīng)時(shí)間大幅度縮短。 （2）高嶺石合成的三種類沸石材料中，鉀霞石的脫汞效率最高，吸附性能最好。同時(shí)，合成的三種類沸石材料的吸附性能都要高于原料高嶺石。 （3）煤矸石在相同的條件下也成功合成了方鈉石、鈣霞石與鉀霞石這些類沸石產(chǎn)物，煤矸石中炭質(zhì)等雜質(zhì)對(duì)合成類沸石結(jié)晶度影響很小。鉀霞石具有很好的熱穩(wěn)定性。 （4）煤矸石合成鉀霞石產(chǎn)物對(duì)汞離子的吸附效率最高，可達(dá)到95.71%。煤矸石合成產(chǎn)物中炭質(zhì)對(duì)汞離子具有一定的吸附性能，這使得煤矸石超臨界水熱合成的產(chǎn)物比高嶺石合成產(chǎn)物的吸附效率高。
[Abstract]:Coal gangue is a kind of hard black rock containing a small amount of carbon, which is one of the industrial solid wastes in our country. A large number of coal gangue occupied cultivated land, and seriously polluted the natural environment. At present, coal gangue is mainly used to make bricks, cement and other building products or to extract chemical products, but the utilization ratio is not high and the added value of products is low. Coal gangue contains a great deal of kaolinite. Kaolinite is a layered silicate clay mineral and one of the ideal raw materials for the synthesis of zeolite molecular sieves. Zeolite molecular sieves have been widely used in many fields such as environmental protection, petrochemical industry, chemical industry and so on. Zeolite synthesized from coal gangue can improve the utilization ratio of coal gangue, and the economic added value of the product is also very high. At present, the main methods of synthesizing zeolites from mineral raw materials include hydrothermal method, alkali solution method, alkali melt hydrothermal method, microwave synthesis method and steam phase synthesis method. The supercritical hydrothermal process has many unique properties: the reaction takes place in a homogeneous environment and is easily dissolved into porous materials, resulting in a high chemical reaction rate. The synthesis of zeolite-like molecular sieves by supercritical hydrothermal method can simplify the synthesis process and greatly shorten the reaction time. In this paper, based on the unique properties of superimminent water, zeolite like zeolite was synthesized by supercritical hydrothermal method with kaolinite and gangue as raw materials. The effects of alkali solution type, alkali solution concentration, supercritical reaction time and temperature on the synthesis of zeolites were investigated. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TG-DTG) and Fourier transform infrared spectroscopy (FTIR). The adsorption properties of the synthesized zeolite-like materials were investigated by removing mercury ions from wastewater. The experimental results show that: When the reaction temperature is 400 鈩

本文編號(hào)：1923050