發(fā)布時(shí)間：2018-01-22 23:43

  本文關(guān)鍵詞： 海泡石 凹凸棒 吸附 飽和吸附量 BCR形態(tài)　出處：《南京理工大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：近年來(lái),隨著工農(nóng)業(yè)的發(fā)展,我國(guó)土壤、河流和湖泊不同程度的存在砷和重金屬污染,頻發(fā)的砷中毒和重金屬污染事件受到廣泛關(guān)注,同時(shí)也強(qiáng)調(diào)了砷和重金屬污染治理的迫切性。本文利用環(huán)境礦物材料的吸附性處理這類污染。砷污染研究的是海泡石和凹凸棒兩種粘土礦物經(jīng)過(guò)改性后對(duì)水體中As3+、As5+的吸附效果,并進(jìn)行實(shí)驗(yàn)室模擬實(shí)驗(yàn)確定兩種材料對(duì)As3+、As5+的飽和吸附量和反應(yīng)平衡時(shí)間以及水環(huán)境的各種因素如pH、粒徑、陰離子(硫酸根、碳酸根、磷酸根)對(duì)吸附效果的影響,通過(guò)動(dòng)態(tài)收集裝置模擬動(dòng)態(tài)吸附過(guò)程。重金屬研究分為水相吸附和沉積物固相固定,水相的吸附研究了兩種材料對(duì)Pb2+和Cd2+的飽和吸附量、吸附平衡時(shí)間和pH的影響,沉積物固相的研究包括材料對(duì)沉積物pH的影響以及對(duì)Pb2+和Cd2+BCR形態(tài)的改變。試驗(yàn)結(jié)果表明未經(jīng)改性的海泡石和凹凸棒對(duì)As3+、As5+的吸附效果較差,而經(jīng)過(guò)800℃熱改性的海泡石和700℃熱改性的凹凸棒對(duì)As3+、As5+表現(xiàn)出極佳的效果,海泡石對(duì)As3+、As5+飽和吸附量分別為27.9mg/g、33.6mg/g,吸附平衡時(shí)間分別為4小時(shí)和1小時(shí)；凹凸棒對(duì)兩者的飽和吸附量分別為68.26mg/g、31.84mg/g,吸附平衡時(shí)間分別為24小時(shí)和4小時(shí)。各因素影響為pH越高,海泡石和凹凸棒對(duì)As3+、As5+的吸附效果越好,粒徑影響較小,硫酸根和碳酸根對(duì)As3+的吸附影響較大,對(duì)As5+影響較小,磷酸根基本沒(méi)有影響,動(dòng)態(tài)吸附效果較差。在pH為6和6.5時(shí),采用原狀海泡石和凹凸棒對(duì)Pb2+、Cd2+進(jìn)行吸附效果較佳,海泡石對(duì)Pb2+、Cd2+的飽和吸附量為27.12mg/g、25.93mg/g,吸附平衡時(shí)間較長(zhǎng),均為24小時(shí)；凹凸棒對(duì)Pb2+、Cd2+的飽和吸附量為26.75mg/g、 24.55mg/g,吸附平衡時(shí)間在24以上。海泡石和凹凸棒的加入使沉積物的pH略有下降,海泡石降低了沉積物中弱酸提取態(tài)、可還原態(tài)的Pb,降低了弱酸提取態(tài)的Cd,對(duì)可氧化態(tài)的Pb、可還原態(tài)的Cd略有提高,凹凸棒對(duì)沉積物的影響規(guī)律與海泡石類似。
[Abstract]:In recent years, with the development of industry and agriculture, arsenic and heavy metal pollution in soils, rivers and lakes in China has been paid more and more attention. At the same time, the urgency of arsenic and heavy metal pollution treatment was emphasized. In this paper, the adsorptive property of environmental mineral materials was used to treat this kind of pollution. Arsenic pollution is studied by using two kinds of clay minerals, sepiolite and attapulgite, which have been modified to the water body. As3. . The adsorption effect of As5, and laboratory simulation experiments were carried out to determine the saturated adsorption capacity and reaction equilibrium time of the two materials to As3 as well as various factors of water environment such as pH, particle size. The influence of anions (sulphate, carbonate, phosphate) on adsorption effect was simulated by dynamic collecting device. Heavy metal adsorption was divided into water adsorption and sediment solid fixation. The effects of two kinds of materials on the saturated adsorption capacity, adsorption equilibrium time and pH of Pb2 and Cd2 were studied. The study of sediment solid phase includes the influence of the material on the pH of sediment and the change of Pb2 and Cd2 BCR morphology. The results show that the unmodified sepiolite and attapulgite have effect on As3. The adsorption effect of As5 was poor, but the sepiolite modified at 800 鈩，

本文編號(hào)：1456058