Abhijit Mondal

Bio: Abhijit Mondal is an academic researcher from National Institute of Technology Agartala. The author has contributed to research in topics: Materials science & Medicine. The author has an hindex of 10, co-authored 19 publications receiving 287 citations. Previous affiliations of Abhijit Mondal include Jadavpur University.

Biosorption of chromium (VI) from aqueous solutions and ANN modelling

Abstract: The use of sustainable, green and biodegradable natural wastes for Cr(VI) detoxification from the contaminated wastewater is considered as a challenging issue. The present research is aimed to assess the effectiveness of seven different natural biomaterials, such as jackfruit leaf, mango leaf, onion peel, garlic peel, bamboo leaf, acid treated rubber leaf and coconut shell powder, for Cr(VI) eradication from aqueous solution by biosorption process. Characterizations were conducted using SEM, BET and FTIR spectroscopy. The effects of operating parameters, viz., pH, initial Cr(VI) ion concentration, adsorbent dosages, contact time and temperature on metal removal efficiency, were studied. The biosorption mechanism was described by the pseudo-second-order model and Langmuir isotherm model. The biosorption process was exothermic, spontaneous and chemical (except garlic peel) in nature. The sequence of adsorption capacity was mango leaf > jackfruit leaf > acid treated rubber leaf > onion peel > bamboo leaf > garlic peel > coconut shell with maximum Langmuir adsorption capacity of 35.7 mg g−1 for mango leaf. The treated effluent can be reused. Desorption study suggested effective reuse of the adsorbents up to three cycles, and safe disposal method of the used adsorbents suggested biodegradability and sustainability of the process by reapplication of the spent adsorbent and ultimately leading towards zero wastages. The performances of the adsorbents were verified with wastewater from electroplating industry. The scale-up study reported for industrial applications. ANN modelling using multilayer perception with gradient descent (GD) and Levenberg-Marquart (LM) algorithm had been successfully used for prediction of Cr(VI) removal efficiency. The study explores the undiscovered potential of the natural waste materials for sustainable existence of small and medium sector industries, especially in the third world countries by protecting the environment by eco-innovation.

Sustainable bioremediation of Cd(II) from aqueous solution using natural waste materials: Kinetics, equilibrium, thermodynamics, toxicity studies and GA-ANN hybrid modelling

Abstract: The paper aims to provide efficient and affordable means for pollution abatement to MSME sector. In this work, the performance of some naturally available bio-waste materials, viz., leaves of jackfruit, mango and rubber plants have been attempted as biosorbents for remediation of toxic Cd(II) from aqueous solution. The biomasses have been characterized to find out the surface morphology, active surface area, presence of characteristic surface groups etc. which facilitate the biosorption process. Batch experiments are conducted to see the effects of operating parameters, viz., aqueous phase pH, initial Cd(II) concentration, adsorbent dose, time, temperature for Cd(II) ion removal onto these green biomaterials. The bioremediation mechanism was strongly pH dependent, spontaneous and followed second-order kinetics. Mass transfer, intra-particle diffusion and chemical adsorption controlled the process. Jackfruit leaf showed the best sorption performance by removing 98.72% Cd(II) from 20 mg L−1 aqueous solution at a dose of 5 g L−1 and the equilibrium adsorption capacity of 20.37 mg g−1. The bio-sorbents performed satisfactory when tested against the industrial wastewater. The toxicity effect of the cadmium ion was analysed on living animal cell and they showed morphological alteration of RBC along with clumped appearance. The cell alteration intensity reduced with the treated effluent. The natural adsorbents have comparable adsorption capacity of other green adsorbents used by different researchers. Modelling of the complex sorption process has been performed using hybrid artificial intelligence (GA-ANN) technique to predict the metal ion removal efficiency accurately and obtained results have good agreement with the experimental data with correlation coefficient (R) ranging from 0.97–0.99. All these findings have manifested application of jackfruit, rubber and mango leaves for removal of Cd(II) ions in an environmentally sustainable and friendly way.

Distillation studies in rotating packed bed with split packing

Abstract: Rotating packed bed (RPB) with split packing has been developed recently to overcome the limitation of negligible tangential slip velocity between vapor and packing obtained with single rotating packing element of conventional RPB design. This work evaluates the performance of this contactor for separation of binary mixture methanol–ethanol by distillation. Experiments were carried out at total reflux condition. The height equivalent of a theoretical plate (HETP) of 2.9 cm was obtained at F -factor = 0.6 (m/s) (kg/m 3 ) 0.5 and rotor speed of 1100 rpm. Comparison with distillation studies reported for this system in the literature indicated that the mass transfer performance of this rotor design was superior to that of conventional RPB. Analysis of the experimental data also suggested that the rotor speed influenced the overall volumetric mass transfer coefficient to a greater degree in this design.

Removal of chromium(VI) from aqueous solutions using rubber leaf powder: batch and column studies

Abstract: Chromium metal is found in industrial wastewater at a much higher concentration than the prescribed limit set by different regulatory authorities. Since chromium(VI) is very toxic and carcinogenic, it requires removal at source, that is, before its discharge to the water bodies. The present study is carried out for removal of Cr(VI) from aqueous solution by using locally available rubber leaf as a low-cost adsorbent in batch and continuous column mode. The effects of pH, adsorbent dose, contact time, initial metal ion concentration, and temperature on removal of Cr(VI) were studied in batch process. Different kinetic and isotherm models were examined and the model parameters were determined. The column studies were conducted to investigate the effects of flow rate, bed height, and initial metal ion concentration on removal efficiencies. The experimental data reflects reasonably with Thomas and Yoon–Nelson models in continuous mode.

Digital Transformation and Environmental Sustainability: A Review and Research Agenda

Abstract: Digital transformation refers to the unprecedented disruptions in society, industry, and organizations stimulated by advances in digital technologies such as artificial intelligence, big data analytics, cloud computing, and the Internet of Things (IoT). Presently, there is a lack of studies to map digital transformation in the environmental sustainability domain. This paper identifies the disruptions driven by digital transformation in the environmental sustainability domain through a systematic literature review. The results present a framework that outlines the transformations in four key areas: pollution control, waste management, sustainable production, and urban sustainability. The transformations in each key area are divided into further sub-categories. This study proposes an agenda for future research in terms of organizational capabilities, performance, and digital transformation strategy regarding environmental sustainability.

Chemical Sensing Applications of ZnO Nanomaterials

Abstract: Recent advancement in nanoscience and nanotechnology has witnessed numerous triumphs of zinc oxide (ZnO) nanomaterials due to their various exotic and multifunctional properties and wide applications. As a remarkable and functional material, ZnO has attracted extensive scientific and technological attention, as it combines different properties such as high specific surface area, biocompatibility, electrochemical activities, chemical and photochemical stability, high-electron communicating features, non-toxicity, ease of syntheses, and so on. Because of its various interesting properties, ZnO nanomaterials have been used for various applications ranging from electronics to optoelectronics, sensing to biomedical and environmental applications. Further, due to the high electrochemical activities and electron communication features, ZnO nanomaterials are considered as excellent candidates for electrochemical sensors. The present review meticulously introduces the current advancements of ZnO nanomaterial-based chemical sensors. Various operational factors such as the effect of size, morphologies, compositions and their respective working mechanisms along with the selectivity, sensitivity, detection limit, stability, etc., are discussed in this article.