Gel-based nanocomposite using persulfate-activated bread crumbs for fulvic acid release and Pb(II) removal
Gel-based nanocomposite using persulfate-activated bread crumbs for fulvic acid release and Pb(II) removal
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DOI：
10.1016/j.cej.2022.137002
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发表时间：
2022-05-18
影响因子：
15.1
通讯作者：
Wang, Dongfang
中科院分区：
文献类型：
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作者：
Cai, Dongqing;Yao, Xia;Wang, Dongfang
面包行业是世界上最大的食品行业之一，全世界每年有数百吨面包被浪费。在本研究中，利用过硫酸盐活化的面包屑释放黄腐酸(FA)并去除二价铅(Pb(II))，制备了凝胶纳米复合黄腐酸面包屑(GN/FABC)。用K2S2O8在碱性条件下处理面包渣，制得FABC。随后，将FABC、生物炭和Fe3O4与海藻酸钠(SA)水溶液混合形成均匀溶液，然后将混合溶液滴加到FeCl3水溶液中生成GN/FABC。其中，SA可与FeCl3交联形成凝胶球。2 h后，FABC中的FA含量达到50 mg/g，面包屑活化过程中的最高温度达到80℃。此外，GN/FABC在水中放置24 h后，FA的平衡释放量达到42 mg/g，同时，GN/FABC对水中铅(II)的去除效率在36 h后可达75%，且其释放机理符合Ritger-Peppas定律，对铅(II)的去除动力学符合准二级模型。值得注意的是，盆栽实验表明，GN/FABC可以抑制铅(II)的生物有效性。本研究为面包废弃物的处理和高效资源化利用提供了一种新的方法。
Breadmaking industry is one of the world's largest food industries, and hundreds of tons of bread are wasted worldwide every year. In this study, a gel nanocomposite fulvic acid-based bread crumb (GN/FABC) was fabricated using persulfate-activated bread crumbs to release fulvic acid (FA) and remove bivalent lead (Pb(II)). Bread crumbs were treated with K2S2O8 under alkaline conditions to produce FABC. Subsequently, the FABC, biochar, and Fe3O4 were mixed with sodium alginate (SA) aqueous to form a homogeneous solution, and the mixed solution was then added dropwise to the FeCl3 aqueous solution to create GN/FABC. Therein, SA could be cross-linked with FeCl3 to form a gel sphere. After 2 h, the FA content in the FABC reached 50 mg/g, and the maximum temperature reached 80 degrees C during the activation of the bread crumbs. Additionally, the equilibrium quantity of FA released from GN/FABC reached 42 mg/g after being in water for 24 h. Meanwhile, the removal efficiency of GN/FABC in water for Pb(II) could be 75% after 36 h. Furthermore, the release mechanism of FA from GN/FABC was consistent with the Ritger-Peppas law and the removal kinetics of Pb(II) followed the pseudo second-order model. Notably, a pot experiment revealed that GN/FABC could inhibit the bioavailability of Pb(II). Thus, this study provided a new method for dealing with bread waste and achieving efficient resource utilization.