【摘要】：核桃殼是一種分布非常廣泛的典型廢棄生物質(zhì),是一種可再生、易生物降解的環(huán)境友好型天然資源。核桃殼作為制備炭材料的原料,可將廢棄生物質(zhì)資源轉(zhuǎn)換為一種制備簡單、性能優(yōu)良的炭材料,是處理環(huán)境污染物的新型的環(huán)保材料。水熱炭化制備水熱炭材料是近年來研究功能性炭材料的課題。本研究選擇核桃殼水熱炭作為制備活性炭材料的前驅(qū)體,建立了制備水熱活性炭的方法并對制備的水熱活性炭材料各性能進(jìn)行表征,結(jié)果如下：(1)在密閉的容器里,以水作為溶劑,溫度對水熱炭化過程的影響最為顯著,調(diào)節(jié)溫度在180-250℃范圍內(nèi)的變化,利用掃描電子顯微鏡、紅外光譜、元素分析等手段表征產(chǎn)物,在溫度240℃水熱條件下,碳含量達(dá)到70.31%,且制備的炭材料熱值隨之提高。利用過程簡單、條件溫和的水熱方法制備活化前驅(qū)體,為后續(xù)活化提供了基本的碳骨架結(jié)構(gòu),可降低整個制備活性炭工藝的成本。(2)選擇碳含量最高的水熱炭材料進(jìn)行化學(xué)活化處理,考察活化溫度(500、600、700、800、900℃)、活化時間(30、60、90、120、150 min)、堿炭比(1：1、2：1、3:1、4：1、5：1)對制備水熱活性炭性能的影響。采用單因素統(tǒng)計(jì)分析和正交優(yōu)化實(shí)驗(yàn)制備最優(yōu)炭材料,通過探討水熱活性炭的結(jié)構(gòu)、比表面積、孔徑孔容以及對亞甲基藍(lán)吸附性能等參數(shù),綜合評價制備水熱活性炭的性能。實(shí)驗(yàn)結(jié)果表明240℃核桃殼水熱炭作為改性的前驅(qū)體,活化溫度為800℃,活化時間為120 min,堿炭比為3：1時,制備的活化水熱炭性能最佳。此時,水熱活性炭對亞甲基藍(lán)的吸附量為498.52 mg/g,比表面積達(dá)2892.70 m2/g,總孔容為1.281 cm3/g,微孔孔容為0.416,表明制備的水熱活性炭材料以微孔為主。其對亞甲基藍(lán)的吸附性能優(yōu)于傳統(tǒng)制備活性炭的吸附性能,為水熱活化方法深入研究提供基礎(chǔ)數(shù)據(jù)。(3)通過對核桃殼水熱活性炭吸附亞甲基藍(lán)影響因素的分析,考察了吸附條件水熱活性炭的投加量、初始濃度、初始pH以及停留時間對吸附過程的影響趨勢,采用動力學(xué)和吸附等溫線對實(shí)驗(yàn)數(shù)據(jù)進(jìn)行擬合,并得到了相應(yīng)的吸附常數(shù)和動力學(xué)常數(shù)。分析結(jié)果Langmuir模型能夠更好地描述活化水熱炭吸附量與吸附亞甲基藍(lán)濃度的關(guān)系,準(zhǔn)二級動力學(xué)模型可描述活化水熱炭吸附亞甲基藍(lán)的動力學(xué)過程,擬合相關(guān)系數(shù)R2達(dá)0.99965。
[Abstract]:Walnut shell is a kind of typical waste biomass which is widely distributed. It is a kind of renewable and biodegradable environment-friendly natural resource. Walnut shell can be used as a raw material to prepare carbon materials, which can convert the waste biomass resources into a kind of carbon material with simple preparation and good performance. In this study, walnut shell hydrothermal carbon was selected as the precursor of the preparation of activated carbon materials, and the preparation method of hydrothermal activated carbon was established. The properties of the prepared hydrothermal activated carbon materials were characterized. The results are as follows: (1) In an airtight container, water was used as the precursor of the preparation of activated carbon materials. Solvent and temperature have the most significant effect on hydrothermal carbonization process. The product is characterized by scanning electron microscopy, infrared spectroscopy and elemental analysis. Under hydrothermal condition of 240 C, the carbon content reaches 70.31%, and the calorific value of the prepared carbon material increases with the increase of temperature. (2) The hydrothermal carbon materials with the highest carbon content were selected for chemical activation treatment, and the activation temperature (500,600,700,800,900 C), activation time (30,60,90,120,150 min), alkali-carbon ratio (1:1,2:1,2,1,000) were investigated. The effects of 3:1,4:1,5:1) on the properties of hydrothermal activated carbon were studied. The optimum carbon materials were prepared by single factor statistical analysis and orthogonal experiment. The properties of hydrothermal activated carbon were comprehensively evaluated by investigating the structure, specific surface area, pore size and adsorption properties of methylene blue. When the activation temperature is 800 C, the activation time is 120 min and the ratio of alkali to carbon is 3:1, the performance of the prepared activated hydrothermal carbon is the best. Hydrothermal activated carbon materials mainly consist of microporous materials. Its adsorption performance for methylene blue is better than that of traditional activated carbon, which provides basic data for further study of hydrothermal activation methods. (3) Through the analysis of influencing factors of adsorption of methylene blue on walnut shell hydrothermal activated carbon, the dosage and initial concentration of hydrothermal activated carbon were investigated. The kinetic and adsorption isotherms were used to fit the experimental data, and the corresponding adsorption constants and kinetic constants were obtained. The Langmuir model can better describe the relationship between the adsorption capacity of activated hydrothermal carbon and the concentration of methylene blue, and the quasi-second-order kinetic force. The kinetic process of adsorption of methylene blue on activated hydrothermal carbon can be described by the model. The fitting correlation coefficient R2 is 0.99965.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：TQ424.1;X505

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 吳艷姣;李偉;吳瓊;劉守新;;水熱炭的制備、性質(zhì)及應(yīng)用[J];化學(xué)進(jìn)展;2016年01期

2 姜偉;朱麗娜;趙仲陽;蔣巖;趙光輝;;生物質(zhì)熱解液化技術(shù)及應(yīng)用前景[J];糧油加工(電子版);2015年12期

3 黃維;范同祥;;水熱碳化法的研究進(jìn)展[J];材料導(dǎo)報;2014年S1期

4 曾淦寧;伍希;艾寧;王家煒;屠美玲;周鴻艷;;銅藻基生物炭的水熱制備及性能表征[J];環(huán)境科學(xué)學(xué)報;2014年02期

5 孫勇;姜永成;王應(yīng)寬;郭君;Richard Griffith;Min Min;;美國生物質(zhì)能源資源分布及利用[J];世界農(nóng)業(yè);2013年10期

6 Marcelo Marques Tusi;Michele Brandalise;Nataly Soares de Oliveira Polanco;Olandir Vercino Correa;Antonio Carlos da Silva;Juan Carlo Villalba;Fauze Jaco Anaissi;Almir Oliveira Neto;Estevam Vitorio Spinac;;Ni/Carbon Hybrid Prepared by Hydrothermal Carbonization and Thermal Treatment as Support for PtRu Nanoparticles for Direct Methanol Fuel Cell[J];Journal of Materials Science & Technology;2013年08期

7 吳倩芳;吳建芝;張付申;;水熱炭化餐廚垃圾制備納米鐵/炭復(fù)合材料[J];環(huán)境工程學(xué)報;2013年02期

8 吳倩芳;張付申;;水熱炭化廢棄生物質(zhì)的研究進(jìn)展[J];環(huán)境污染與防治;2012年07期

9 郝一男;王喜明;丁立軍;;超聲波處理文冠果果殼制備的活性炭對亞甲基藍(lán)溶液的吸附[J];東北農(nóng)業(yè)大學(xué)學(xué)報;2011年11期

10 高英;石韜;汪君;陳漢平;王賢華;楊海平;;生物質(zhì)水熱技術(shù)研究現(xiàn)狀及發(fā)展[J];可再生能源;2011年04期

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