本文選題：VOCs　切入點(diǎn)：活性炭改性　出處：《西南交通大學(xué)》2017年碩士論文

【摘要】：家具涂裝業(yè)是VOCs主要的工業(yè)源之一,其VOCs處理工藝也越來越受到重視。吸附工藝是家具涂裝業(yè)最主要的VOCs處理工藝,活性炭是最常用的吸附劑。吸附處理工藝具有凈化效率高、設(shè)備簡(jiǎn)單等優(yōu)點(diǎn)。但是,吸附工藝中仍存在諸多問題需要改進(jìn),如吸附劑量大、定期更換等。如何提高吸附劑的吸附性能成為降低吸附工藝的成本的主要措施。本文通過硝酸改性、氫氧化鈉改性、高溫改性方法改性活性炭,采用Boehm滴定法測(cè)定了改性活性炭表面含氧官能團(tuán)的含量,并研究了改性后活性炭對(duì)甲苯的吸附性能。研究結(jié)果如下:(1)Boehm滴定實(shí)驗(yàn):硝酸改性活性炭表面酸性基團(tuán)增加,堿性基團(tuán)減少,表面酸性基團(tuán)比重增大。氫氧化鈉改性活性炭表面酸性基團(tuán)減少,堿性基團(tuán)沒有明顯變化,表面堿性基團(tuán)比重增加。酸堿改性活性炭表面含氧基團(tuán)都隨著改性液的濃度增大變化量的越大。高溫改性活性炭表面酸性基團(tuán)隨著溫度的增大逐漸減少,堿性基團(tuán)逐漸增加,同樣表面堿性基團(tuán)比重增加。(2)活性炭靜態(tài)吸附實(shí)驗(yàn):硝酸改性與氫氧化鈉改后性活性炭對(duì)甲苯的吸附飽和量沒有明顯變化;高溫改性后活性炭隨著改性溫度升高對(duì)甲苯的吸附飽和量增加,800℃時(shí)達(dá)到195 mg/g。(3)活性炭吸附動(dòng)態(tài)實(shí)驗(yàn):原活性炭吸附穿透時(shí)間為120min,20%硝酸改性和800℃高溫改性活性分別推遲30 min和60 min。(4)吸附床高度的不同影響吸附穿透時(shí)間的不同,隨著吸附床層高度的增加,穿透時(shí)間相應(yīng)增大。根據(jù)希洛夫公式兩者呈線性關(guān)系,經(jīng)擬合得出800℃改性活性炭的穿透作用系數(shù)K=25.5 min/cm,吸附穿透時(shí)間損失t_0=110 min。
[Abstract]:The furniture coating industry is one of the main industrial sources of VOCs, and its VOCs treatment technology has been paid more and more attention.Adsorption process is the most important VOCs treatment process in furniture painting industry, activated carbon is the most commonly used adsorbent.Adsorption treatment process has the advantages of high purification efficiency and simple equipment.However, there are still many problems in adsorption process, such as large amount of adsorbent, regular replacement and so on.How to improve the absorbability of adsorbent is the main measure to reduce the cost of adsorption process.In this paper, the modified activated carbon was modified by nitric acid, sodium hydroxide and high temperature. The content of oxygen functional groups on the surface of modified activated carbon was determined by Boehm titration, and the adsorption property of modified activated carbon to toluene was studied.The results are as follows: the surface acidic group of activated carbon modified by nitric acid increases, the basic group decreases, and the specific gravity of surface acidic group increases.The surface acidic group of activated carbon modified by sodium hydroxide decreased, but the basic group did not change obviously, and the specific gravity of surface basic group increased.The surface oxygen groups of acid-base modified activated carbon increased with the increase of the concentration of the modified solution.The surface acidic group of high temperature modified activated carbon decreases gradually with the increase of temperature, and the basic group increases gradually.At the same time, the specific gravity of basic group on the surface increased. 2) the static adsorption experiment of activated carbon: the saturated amount of toluene adsorbed by activated carbon modified by nitric acid and sodium hydroxide did not change obviously;Adsorption of toluene by activated carbon at 800 鈩，

本文編號(hào)：1703150