Elmes Victoria K, Hurt Andrew P, Coleman Nichola J
School of Science, Faculty of Engineering and Science, University of Greenwich, Chatham Maritime, Kent ME4 4TB, UK.
Materials (Basel). 2021 Aug 27;14(17):4887. doi: 10.3390/ma14174887.
This study investigated the one-pot hydrothermal synthesis of mixed-phase ion-exchangers from waste amber container glass and three different aluminium sources (Si/Al = 2) in 4.5 M NaOH at 100 °C. Reaction products were characterised by X-ray diffraction analysis, Fourier transform infrared spectroscopy, Al and Si magic angle spinning nuclear magnetic resonance spectroscopy and scanning electron microscopy at 24, 48 and 150 h. Nitrated forms of cancrinite and sodalite were the predominant products obtained with reagent grade aluminium nitrate (Al(NO)∙9HO). Waste aluminium foil gave rise to sodalite, tobermorite and zeolite Na-P1 as major phases; and the principal products arising from amorphous aluminium hydroxide waste were sodalite, tobermorite and zeolite A. Minor proportions of the hydrogarnet, katoite, and calcite were also present in each sample. In each case, crystallisation was incomplete and products of 52, 65 and 49% crystallinity were obtained at 150 h for the samples prepared with aluminium nitrate (AN-150), aluminium foil (AF-150) and amorphous aluminium hydroxide waste (AH-150), respectively. Batch Pb-uptake (~100 mg g) was similar for all 150-h samples irrespective of the nature of the aluminium reagent and composition of the product. Batch Cd-uptakes of AF-150 (54 mg g) and AH-150 (48 mg g) were greater than that of AN-150 (36 mg g) indicating that the sodalite- and tobermorite-rich products exhibited a superior affinity for Cd ions. The observed Pb- and Cd-uptake capacities of the mixed-product ion-exchangers compared favourably with those of other inorganic waste-derived sorbents reported in the literature.
本研究考察了在100℃下，于4.5M氢氧化钠溶液中，由废弃琥珀色容器玻璃与三种不同铝源（硅铝比=2）通过一锅水热法合成混合相离子交换剂。在反应24、48和150小时时，通过X射线衍射分析、傅里叶变换红外光谱、铝和硅魔角旋转核磁共振光谱以及扫描电子显微镜对反应产物进行了表征。用试剂级硝酸铝（Al(NO)∙9HO）得到的主要产物是硝化形式的钙霞石和方钠石。废铝箔产生的主要相为方钠石、雪硅钙石和钠型P1沸石；而由无定形氢氧化铝废料产生的主要产物是方钠石、雪硅钙石和A型沸石。每个样品中还存在少量的水榴石、水钙铝榴石和方解石。在每种情况下，结晶都不完全，对于用硝酸铝（AN - 150）、铝箔（AF - 150）和无定形氢氧化铝废料（AH - 150）制备的样品，在150小时时分别获得了结晶度为52%、65%和49%的产物。无论铝试剂的性质和产物组成如何，所有150小时的样品对铅的批量吸附量（约100mg/g）相似。AF - 150（54mg/g）和AH - 150（48mg/g）对镉的批量吸附量大于AN - 150（3mg/g），这表明富含方钠石和雪硅钙石的产物对镉离子具有更高的亲和力。混合产物离子交换剂对铅和镉的吸附能力与文献中报道的其他无机废物衍生吸附剂相比具有优势。
