Environmental-friendly montmorillonite-biochar composites: Facile production and tunable adsorption-release of ammonium and phosphate
Environmental-friendly montmorillonite-biochar composites: Facile production and tunable adsorption-release of ammonium and phosphate
复制标题
环保型蒙脱土-生物炭复合材料：生产简便且可调节铵和磷酸盐的吸附释放
DOI：
10.1016/j.jclepro.2017.04.050
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发表时间：
2017-07-10
影响因子：
11.1
通讯作者：
Chu, Mao Quan
中科院分区：
文献类型：
--
作者：
Chen, Liang;Chen, Xiao Long;Chu, Mao Quan
清洁生产环境友好材料，以控制废水处理和土壤肥力维持中的铵和磷的吸附和解吸，是一项挑战。在这里，我们展示了一类粘土矿物-生物炭复合材料，它是由两种丰富的天然原料(蒙脱石和竹粉)通过简单、清洁的热解过程制备的。用X射线粉末衍射、傅里叶变换红外光谱、氮气吸附/脱附等温线、热重分析和扫描电子显微镜对蒙脱土-生物炭复合材料(MBC)进行了表征。考察了MBC样品对水溶液中NH4+和PO43-的吸附和缓释特性。蒙脱石(Mt)作为固体酸催化剂，催化竹粉热解生成生物炭，降低了热解温度。生物炭和蒙脱土都有助于提供不同的表面和不同的吸附位置的织构和结构。其最大吸附容量分别为12.52mg.g(-1)和105.28 mg.g(-1)。NH4+在MBC样品上的吸附主要受表面吸附控制，部分受CEC过程控制。PO43-的吸附能力来自于PO43-与MBC样品中的钙、镁、铝、铁等阳离子之间的静电吸引或离子键作用。富含NH4+和PO43-的MBC样品在2-88h内NH4+和PO43-的释放率仅为0.30-4.92%和2.63-5.09%。这些结果表明，用低成本的MT和竹子制备的MBC样品可以通过吸附去除水溶液中的NH4+和PO43-，生成的富含NH4+和PO43-的MBC样品可以用作N和P的有效缓释肥料。(C)2017爱思唯尔有限公司。
The cleaner production of environmentally friendly materials for the controlled adsorption and desorption of ammonium and phosphate in wastewater treatment and soil fertility maintenance is a challenge. Here we show that a class of clay mineral-biochar composites which were produced via a facile cleaner pyrolysis process starting from two abundant natural materials (montmorillonite and bamboo powder). The montmorillonite-biochar composites (MBC) were characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy, N-2 adsorption/desorption isotherms, thermogravimetric analysis, and scanning electron microscopy. The adsorption and slow-release characteristics of MBC samples for NH4+ and PO43- in aqueous solution were evaluated. Montmorillonite (Mt) acted as a solid acidic catalyst and catalyzed the pyrolysis of bamboo powder to biochar and lower the pyrolysis temperatures. Both biochar and Mt contributed to the texture and structure, which provided varied surface and various adsorptive sites. The Langmuir maximum adsorption capacity of MBC samples for NH4+ and PO43- was 12.52 mg.g(-1) and 105.28 mg.g(-1). The adsorption of NH4+ onto the MBC sample was primarily controlled by surface adsorption and partially by a CEC process. The adsorption capacity of PO43- resulted from the electrostatic attraction or ionic bonding between PO43- and cations in the MBC samples such as Ca2+, Mg2+, Al3+ and Fe3+. The release of NH4+ and PO43- from the NH4+- and PO43--laden MBC samples was merely 0.30-4.92% and 2.63-5.09% within 2-88 h. These findings implied that the MBC samples prepared from low-cost Mt and bamboo can remove NH4+ and PO43- from aqueous solution by adsorption and the resultant NH4+- and PO43--laden MBC samples can be used as an effective slow release fertilizer of N and P. (C) 2017 Elsevier Ltd. All rights reserved.