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This study investigates the possibility of enhancing Artocarpus odoratissimus leaves (TL) through surface modification with a base, NaOH (TLN), a surfactant, SDS (TLS) and a chelating agent, EDTA (...

As an extension to successful adsorption of malachite green dye onto Artocarpus odoratissimus (Tarap) leaves, the surface of the leaves was modified by using a strong base, namely sodium hydroxide (NaOH). The isotherm was best fitted to the Redlich–Peterson model. Based on monolayer adsorption using Langmuir model, the q m a x value of Tarap leaves enhanced from 254.9 to 422.0 mg/g upon the modification, and increased by 3 fold when using the Sips model. This paper provided a better insight on the types of reactions that occurred during the adsorption process and the strength of attractions between adsorbent–adsorbate supported with the aid of multiple characterization methods. Other influencing parameters on adsorption such as contact time, ionic strength, pH, temperature and initial dye concentrations were also studied.

Leaves of Artocarpus odoratissimus have successfully undergone surface chemical modification using a base (NaOH) and a chelating agent (EDTA) via a single and double modification. The modified adsorbents were investigated for their potential use in adsorbing Pb(II) from simulated wastewater and were tested through several adsorption parameters such as pH, ionic strength, interference effect, regeneration and column (dynamic) studies. The adsorption of Pb(II) by the adsorbents was excellent where the removal of Pb(II) was almost resilient to change of pH, except at pH 2, and unaffected by the presence of other metal ions. Further, the adsorbents can be regenerated using acid and base, maintaining good adsorption even at the 4th cycle. The dynamic study concluded that column containing higher bed heights of the adsorbent took more time to exhaust and able to adsorb more volume of the Pb(II). Adsorption isotherm data point to double modified adsorbent has higher adsorption capacity than the untreated and single modified adsorbents. This study also showed that the kinetics of all the adsorbents was following pseudo-second order indicating that the adsorption processes were all chemisorption.

In this study, the feasibility of utilizing Artocarpus odoratissimus skin (“Tarap” skin or TS) as a potential adsorbent for the removal of crystal violet dye was investigated. X-ray fluorescence, Fourier Transform Spectroscopic, and scanning electron microscopic investigation of TS and its NaOH-treated form (NaOH-TS) before and after interaction with crystal violet (CV) cationic dye indicate that the dye shows a strong affinity toward the adsorbent, which is enhanced upon the treatment with a NaOH solution. Decrease in the concentration of metal ions on the TS/NaOH-TS is indicative of the contribution of an ion-exchange mechanism owing to the positive charge of CV molecules. Comparison of experimental adsorption curves with calculated curves point the way toward the agreement with the Langmuir isotherm among the six models tested (Langmuir, Freundlich, Temkin, Dubinin–Radushkevich, Redlich–Peterson, and Sips) under optimized conditions with maximum adsorption capacity of 118 mg g−1 for TS which is...

Several materials have been studied for the adsorption of ammonium ion from synthetic solution. Zeolite is having the highest adsorption capacity (3.160 mg/g) with fast reaction time followed by chitosan (2.5770 mg/g). Activated carbon derived from Tarap (Artocarpus odoratissimus) and rice husk shows better performance than the low cost bleached fibres.

Artocarpus odoratissimus (Tarap) skin shows great potential as an effective low-cost biosorbent for toxic dyes, methylene blue (MB), and methyl violet 2B (MV). The Langmuir adsorption isotherm leads to the maximum biosorption capacities of this biomass, whose point of zero charge was at pH 4.4, of 0.577 mmol g−1 (184.6 mg g−1) and 0.349 mmol g−1 (137.3 mg g−1) for MB and MV, respectively. The Sips isotherm model is the best fit for adsorption of MB, while both the Langmuir and Sips models are in good agreement for MV. Mass transfer of dye species from solution to the biosorbent phase is fast with 50% dye being removed in less than 1 min following the pseudo-second-order kinetics.

Chemical modification of surfaces on Artocarpus odoratissimus leaves (TL) has been performed to enhance the applications of bear surfaces to improve biosorption ability toward methyl violet dye. Adsorption reactivity of both unmodified and modified TL is not sensitive to pH and ionic strength changes in the medium, indicating ease of optimization procedures for most efficient biosorption ability. Significant enhancement of adsorption capacity of modified TL, from 139.7 to 1004.3 mg g−1, is confirmed through adsorption equilibrium experiments, which fulfills the Langmuir model. Adsorption followed the pseudo-second-order kinetics, where a twofold increase in the rate constant was observed upon modification of TL. Modified TL was able to maintain high adsorption capacity even after five cycles of adsorption–regeneration. Therefore, from this study, TL has a great potential as a low-cost adsorbent for real-life environmental remediation application.

This study investigates the potential of the stem axis of Artocarpus odoratissimus fruit (TSA) as an adsorbent for the removal of methyl violet 2B (MV). The functional group analysis was carried out using Fourier-transform infrared spectroscopy. Investigation of the effects of pH and ionic strength provide insights on the involvement of electrostatic attraction and hydrophobic–hydrophobic attraction between the adsorbent and adsorbates. Kinetics models (pseudo-first-order, pseudo-second-order, Weber–Morris and Boyd) and isotherm models (Langmuir, Freundlich and Dubinin–Raduskevich) were used for characterising the adsorption process. The Langmuir model predicted a high q m of 263.7 mg g−1. Thermodynamics studies indicate the adsorption system is spontaneous, endothermic and physical sorption dominant. The spent adsorbent was successfully regenerated using water and obtained adsorption capacity close to the unused adsorbent even after fifth cycle of washing.