Abstract：
Nanocellulose@chitosan (nc@ch) composite beads were prepared via coagulation technique for the elimination of malachite green dye from aqueous solution. As malachite green dye is highly used in textile industries for dyeing purpose which after usage shows fatal effects to the ecosystems and human beings also. In this study the formulated nanocellulose@chitosan composite beads were characterized by Particle size analysis (PSA), Field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis were done to evaluate nanoparticles size distribution, morphological behaviour, functional group entities and degree of crystallinity of prepared beads. The nanocomposite beads adsorption performance was investigated for malachite green (MG) dye and BET analysis were also recorded to know about porous behaviour of the nanocomposite beads. Maximum removal of malachite green (MG) dye was found to be 72.0 mg/g for 100 ppm initial dye concentration. For accurate observations linear and non-linear modelling was done to know about the best-fitted adsorption model during the removal mechanism of dye molecules, on evaluating it has been observed that Langmuir isotherm and Freundlich isotherm show best-fitted observation in the case of linear and non-linear isotherm respectively (R2 = 0.96 & R2 = 0.957). In the case of kinetic linear models, the data was well fitted with pseudo-second-order showing chemosorption mechanism (R2 = 0.999), and in the case of non-linear kinetic model pseudo first order showed good fit showing physisorption mechanism during adsorption (R2 = 0.999). The thermodynamic study showed positive values for ΔH° and ΔS° throughout the adsorption process respectively, implying an endothermic behaviour. In view of cost effectiveness, desorption or regeneration study was done and it was showed that after the 5th cycle, the removal tendency had decreased from 48 to 38 % for 20-100 ppm dye solution accordingly. Thus, nanocomposite beads prepared by the coagulation method seem to be a suitable candidate for dye removal from synthetic wastewater and may have potential to be used in small scale textile industries for real wastewater treatment.
摘要：
通过混凝技术制备了纳米纤维素@壳聚糖（nc@ch）复合珠，用于从水溶液中消除孔雀石绿染料。由于孔雀石绿染料在纺织工业中广泛用于染色目的，使用后对生态系统和人类也显示出致命的影响。在这项研究中，通过粒度分析（PSA）对配制的纳米纤维素@壳聚糖复合珠进行了表征，场发射扫描电子显微镜（FESEM），进行了傅里叶变换红外光谱(FTIR)和X射线衍射(XRD)分析以评估纳米颗粒的尺寸分布,形态学行为，官能团实体和制备的珠的结晶度。研究了孔雀石绿（MG）染料的纳米复合珠吸附性能，并记录了BET分析以了解纳米复合珠的多孔行为。对于100ppm初始染料浓度，孔雀石绿（MG）染料的最大去除率为72.0mg/g。为了获得准确的观察结果，进行了线性和非线性建模，以了解染料分子去除机理过程中最佳拟合的吸附模型。在评估时，已经观察到Langmuir等温线和Freundlich等温线分别在线性和非线性等温线的情况下显示出最佳拟合的观察结果（R2=0.96和R2=0.957）。在动力学线性模型的情况下，数据与显示化学吸附机制的伪二阶拟合良好(R2=0.999)，在非线性动力学模型的情况下，伪一级显示出良好的拟合，表明吸附过程中的物理吸附机制（R2=0.999）。热力学研究显示，在整个吸附过程中，ΔH°和ΔS°分别为正值，暗示吸热行为。考虑到成本效益，进行了解吸或再生研究，结果表明，在第5个循环后，因此，对于20-100ppm染料溶液，去除趋势从48％降低到38％。因此，通过混凝方法制备的纳米复合珠似乎是从合成废水中去除染料的合适候选物，并且可能有潜力用于小规模纺织工业的实际废水处理。
