發(fā)布時(shí)間：2018-05-28 06:34

  本文選題：固定化菌糠 + 生物吸附　； 參考：《東北農(nóng)業(yè)大學(xué)》2015年碩士論文

【摘要】：食用菌菌糠是食用菌工業(yè)生產(chǎn)的固體廢棄物,直接排放到環(huán)境中容易對(duì)生態(tài)環(huán)境造成污染。菌糠上的官能有效基團(tuán)非常之多,可以被用來作為吸附劑來清除廢水體中的有害金屬離子。傳統(tǒng)的廢水處理法有很多缺點(diǎn),而用菌糠來吸附重金屬的價(jià)格低廉、消耗小、對(duì)環(huán)境不存污染。但直接將菌糠投入水體中進(jìn)行吸附,不利于吸附劑的再回收利用,可能導(dǎo)致其在水體中腐化,造成二次污染。本文通過海藻酸鈉-聚乙烯醇對(duì)菌糠的固定化實(shí)驗(yàn),制備出成分一致的顆粒。SA-PVA固定的菌糠吸附材料有以下優(yōu)點(diǎn):1、球狀吸附材料易于回收,便于裝入填充柱、塔中,有利于與生產(chǎn)實(shí)際接軌;2、SA-PVA固定化菌糠在吸附中不易破碎,且其多孔性更加有利于與重金屬離子更好充分的結(jié)合;3、菌糠中木質(zhì)素、纖維素、菌絲體等物質(zhì)提供了大量與重金屬離子結(jié)合的官能團(tuán);4、原料易于獲得,且成本低廉。使用SA-PVA固定化菌糠對(duì)鉛、銅、鋅、鎘這四種金屬進(jìn)行吸附效果的考察。結(jié)果顯示出當(dāng)pH為5~6之間,吸附溫度超過25℃,溶液初始濃度在100-200mg/L之間時(shí),固定化的菌糠對(duì)這幾種金屬可以超過60mg/g吸附量值。本實(shí)驗(yàn)著重對(duì)固定化菌糠對(duì)鎘離子的吸附進(jìn)行探討,確定了單因素吸附條件:p H5,吸附溫度25℃和初始濃度為100mg/L的情況下吸附鎘離子時(shí)效果最好,吸附量甚至達(dá)70mg/g以上。對(duì)鎘離子的吸附優(yōu)先符合Langmuir吸附等溫曲線,且R2值為0.998,從中可以初步判定固定化菌糠對(duì)鎘的吸附為化學(xué)的單層吸附過程。然后利用SEM、FTIR、XRD、BET等儀器對(duì)其吸附的原理進(jìn)行探討解釋,顯示固定化菌糠的比表面積為51.1546m2/g,固定化菌糠對(duì)鎘離子的吸附主要由物理和化學(xué)吸附兩部分組成,包括配位、靜電吸附和絡(luò)合等反應(yīng),且吸附過程中羧基羥基、氨基等基團(tuán)起到主要作用。在吸附-解吸附循環(huán)過程中,HCl被用來作洗脫劑,雖然Cd的洗脫率有所下降趨勢(shì),但到第五次循環(huán)時(shí)洗脫率僅比首次下降了15%。將固定好的菌糠裝入循環(huán)柱中,在最適條件下對(duì)Cd2+廢水的吸附進(jìn)行模擬生產(chǎn)操作,測(cè)得其吸附容量與實(shí)驗(yàn)結(jié)果基本一致。實(shí)驗(yàn)結(jié)果表明,固定化菌糠因其較強(qiáng)的吸附能力、易于回收的特性以及低廉的價(jià)格,具有較大的開發(fā)潛力和較高的應(yīng)用價(jià)值。
[Abstract]:Mushroom bran is a solid waste produced by edible fungus industry. It is easy to pollute the ecological environment when it is discharged directly into the environment. The functional effective groups on the bacterial bran are very numerous and can be used as adsorbents to remove harmful metal ions from the waste water. The traditional wastewater treatment method has many disadvantages, but the use of bacterial bran to adsorb heavy metals is low in price, low in consumption, and no pollution to the environment. However, it is unfavorable to reuse the adsorbent by directly putting the bacterial bran into the water body for adsorption, which may lead to the corruption and secondary pollution of the adsorbent. In this paper, through the immobilization experiment of sodium alginate and polyvinyl alcohol on the bacterial bran, the adsorption material fixed with the same composition of particle. SA-PVA has the following advantages: 1. The spherical adsorption material is easy to be recovered and easily packed into the packed column and column. The immobilized microbial bran is not easy to be broken in the adsorption process, and its porous property is more favorable to better and more fully binding with heavy metal ions, lignin and cellulose in the bacterial bran. Mycelium and other substances provide a large number of heavy metal ions bound to the functional group 4, the raw materials are easy to obtain, and the cost is low. The adsorption effects of lead, copper, zinc and cadmium on lead, copper, zinc and cadmium were investigated by SA-PVA immobilized bacterial bran. The results show that when pH is between 5 ~ 6, adsorption temperature is more than 25 鈩，

本文編號(hào)：1945684