Daochalermwong Amphol, Chanka Napassorn, Songsrirote Kriangsak, Dittanet Peerapan, Niamnuy Chalida, Seubsai Anusorn
Department of Chemical Engineering, Faculty of Engineering; Center of Excellence on Petrochemical and Materials Technology; and Research Network of NANOTEC-KU on NanoCatalysts and NanoMaterials for Sustainable Energy and Environment, Kasetsart University, Bangkok 10900, Thailand.
Department of Chemistry, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand.
ACS Omega. 2020 Mar 5;5(10):5285-5296. doi: 10.1021/acsomega.9b04326. eCollection 2020 Mar 17.
Since large amounts of pineapple leaves are abandoned after harvest in agricultural areas, the possibility of developing value-added products from them is of interest. In this work, cellulose fiber was extracted from pineapple leaves and modified with ethylenediaminetetraacetic acid (EDTA) and carboxymethyl (CM) groups to produce Cell-EDTA and Cell-CM, respectively, which were then used as heavy metal ion adsorbents. A solution of either lead ion (Pb) or cadmium ion (Cd) was used as wastewater for the purpose of studying adsorption efficiencies. The adsorption efficiencies of Cell-EDTA and Cell-CM were significantly higher than those of the unmodified cellulose in the pH range 1-7. Maximum adsorptions toward Pb and Cd were, for Cell-EDTA, 41.2 and 33.2 mg g, respectively, and, for Cell-CM, 63.4 and 23.0 mg g, respectively. The adsorption behaviors of Cell-CM for Pb and Cd fitted well with a pseudo-first-order model, but those of Cell-EDTA for Pb and Cd fitted well with a pseudo-second-order model. All of the adsorption behaviors could be described using the Langmuir adsorption isotherm. Desorption studies of Pb and Cd on both adsorbents using 1 M HCl suggested that regenerability of Cell-EDTA was, for both adsorbates, better than that of Cell-CM. Moreover, adsorption measurements in a mixture of Pb and Cd at various ratios showed that for both adsorbents the adsorption of Pb was higher than that of Cd, while the adsorption selectivity for Pb of Cell-CM was greater than that of Cell-EDTA. This study showed that the modified cellulosic adsorbents made from pineapple leaves were able to efficiently adsorb metal ions.
由于在农业产区收获后会废弃大量菠萝叶，因此开发其高附加值产品具有重要意义。在本研究中，从菠萝叶中提取纤维素纤维，并用乙二胺四乙酸（EDTA）和羧甲基（CM）基团对其进行改性，分别制备了Cell-EDTA和Cell-CM，然后将它们用作重金属离子吸附剂。以铅离子（Pb）或镉离子（Cd）溶液作为废水，研究吸附效率。在pH值为1-7的范围内，Cell-EDTA和Cell-CM的吸附效率显著高于未改性纤维素。对于Cell-EDTA，对Pb和Cd的最大吸附量分别为41.2和33.2 mg/g，对于Cell-CM，分别为63.4和23.0 mg/g。Cell-CM对Pb和Cd的吸附行为符合准一级模型，但Cell-EDTA对Pb和Cd的吸附行为符合准二级模型。所有吸附行为均可用Langmuir吸附等温线描述。用1 M HCl对两种吸附剂上的Pb和Cd进行解吸研究表明，对于两种吸附质，Cell-EDTA的再生能力均优于Cell-CM。此外，在不同比例的Pb和Cd混合物中进行吸附测量表明，对于两种吸附剂，Pb的吸附量均高于Cd，而Cell-CM对Pb的吸附选择性大于Cell-EDTA。本研究表明，由菠萝叶制成的改性纤维素吸附剂能够有效吸附金属离子。
