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• Developed molecular structure descriptor (MSD) to extract molecular feature. • Introduce a hybrid descriptor by combination of MSD and group contribution (GC) • Application of GPR, LightGBM, and CatBoost for forecasting models. • Interpretation model is proposed to analyse the importance of molecular feature. In this work, we investigated three different machine learning (ML)-based models, i.e., gaussian process regression (GPR), LightGBM, and CatBoost, for predicting the solubility of CO 2 in various ionic liquids (ILs). Three molecular descriptors, i.e., group contribution (GC), molecular structure descriptors (MSD), and hybrid GC-MSD are used in our three models. The performance of our developed models were rigorously evaluated using mean absolute error (MAE), coefficient of determination (R2), and mean relative error (MRE) (i.e., relative deviation in percentage), with each model subjected to multiple tests employing different random state parameters. The dataset underwent partitioning into training and testing sets at an 80:20 ratio, with additional splits at various ratios to assess prediction performance sensitivity. Overall, all models exhibited proficient CO 2 solubility prediction in ILs, with performance varying based on descriptor type. Notably, the hybrid GC-MSD consistently outperformed others, attributed to GC-MSD incorporates a broader array of molecular feature information. Particularly, the CatBoost-GC-MSD model excelled, achieving an impressive R2 of 0.9925, MAE of 0.0122, and MRE of 11.1550%. Comparing our models to previous studies revealed the superior performance of CatBoost-GC-MSD across all descriptor types. Furthermore, our model interpretation, employing shapley additive explanation (SHAP) analysis, identified pressure, temperature, Chi0, Kappa2, and EState_VSA10 as the top five influential input features. These findings provide valuable insights into the underlying molecular features affecting CO 2 solubility in ILs and lay the foundation for future research in this field. [ABSTRACT FROM AUTHOR]

• A novel heterogeneous triple-column distillation (NHTCD) without solvent injection. • Simplification of previously established extractive distillation (ED) process. • Enhanced with heat integration (HI) and heat pump-vapor recompression (HP-VR). • HP-VR with HI NHTCD provides 87 %, 57 %, and 86 % lower energy, cost, and emission. • Conceptual design based on thermodynamic insights. The challenging separation of ethyl acetate (EtAC) and methanol (MeOH) from wastewater involves two azeotropes and a distillation boundary. Although extractive distillation (ED) has been explored, the heterogeneous region within the ternary azeotropic mixture has been overlooked, which suggests the possibility of using a decanter to cross the distillation boundary when the feed composition is present in the heterogeneous region. This study introduces a novel heterogeneous triple-column distillation (NHTCD) that eliminates the external solvent injection, simplifying the complex ED processes. The NHTCD process is developed via a systematic approach, comprising conceptual design based on thermodynamic insights and process optimization to determine the optimum configuration. Furthermore, heat integration (HI) and heat pump-vapor recompression (HP-VR) techniques were explored for energy conservation. Evaluation of energy, economic, and environmental (3E) aspects shows that the hybrid HP-VR with HI NHTCD process outperforms ED, achieving 87 %, 57 %, and 86 % reductions in energy, economic, and environmental emissions, respectively. [ABSTRACT FROM AUTHOR]

A thermally coupled azeotropic dividing wall column (ADWC) configuration is explored for the separation of industrial wastewater to recycle the organic solvent tert-butanol. Heat pump technology is used to the ADWC configuration to improve the released heat duty quality of the condenser achieving the energy-saving. A gas preheater before the compressor is installed in the heat pump assisted ADWC configuration in increasing the temperature of the inlet vapour stream of the compressor that achieves effectively reducing the power and compression ratio of the compressor. To fully utilize a large amount of superheat energy produced in heat pump system indicated by the temperature-enthalpy and Grand Composite Curve diagrams, a green and sustainable Heat Integrated ADWC (HI-ADWC) separation configuration is proposed by the combined use of heat exchange network and heat pump implementations. Three indexes involving total annual cost, CO 2 emissions, and exergy loss are introduced to evaluate the economic, environmental and thermodynamic performances. The results illustrate that the TAC of the proposed green and sustainable HI-ADWC configuration is significantly reduced by 32.91% with a ten-year payback period compared to that of the existing configuration. CO 2 emissions are reduced by 86.43% and exergy loss of the HI-ADWC configuration by 36.72%. The proposed method for the green and sustainable HI-ADWC configuration could be widely extended to other industrial processes reduce energy consumption and related CO 2 emissions. Image 1 • Heat pump-azeotropic dividing wall column is proposed for tert-butanol dehydration. • Temperature-enthalpy and Grand Composite Curves are used to analyze heat recovery. • The preheater and heat exchanger network methods are used for further energy-saving. • The heat integrated configuration has best economic and environmental performances. [ABSTRACT FROM AUTHOR]

Abstract The design of the diethyl carbonate (DEC) production process has received much attention due to its key role as the oxygenated gasoline additive with much fewer environmental and health issues than methyl tert -butyl ether. In this study, two configurations including vapor recompression heat pump (VRHP)-reactive dividing wall column (RDWC) with or without the splitting top stream are investigated for DEC production to screen out the best VRHP sequence. Furthermore, a novel alternative approach of different pressure thermally coupled-RDWC (DPTC-RDWC) is comparatively proposed to achieve less capital and energy cost. The effects of pressure within stripping section of the RDWC on total annualized cost (TAC) and the temperature difference between the condenser and reboiler are studied. The results illustrate that the proposed optimum process produces DEC production with the purity of 99.8 mol% and significant reduction of TAC is achieved by 20.52% with 10 years payback period. Apart from that, carbon dioxide emission of the process is decreased by 33.74% compared to that through conventional RDWC. Highlights • VRHP-RDWC with or without a splitting top stream is explored for DEC synthesis. • A novel DPTC-RDWC is proposed to achieve the less capital and energy cost. • TAC of the proposed DPTC-RDWC is reduced by 20.52% compared to the RDWC process. • CO 2 emissions of the proposed DPTC-RDWC are reduced by 33.74% compared to the RDWC. [ABSTRACT FROM AUTHOR]

[Display omitted] • Increasing nutrient loads and turbidity were the most apparent environmental variations. • MP and S1 occupied more dominance with higher abundance but lower diversity. • Decreased RF and increased MCF implied zooplankton community toward large size. • Nutrients and turbidity considerably drove the plankton community's turnover. Urbanization causes immense eutrophication pressure on small urban wetlands, which play a vital role in urban ecosystems. However, our comprehension of the prolonged impacts of eutrophication on these types of wetlands continues to be significantly limited. To address this knowledge gap, we analyzed monthly physical–chemical variables and seasonal phytoplankton and zooplankton communities at the Taipa-Coloane wetland in Macau, China, from 2013 to 2019. Through the generalized additive model (GAM) and principal component analysis (PCA), we found that the aquatic system mainly exhibited interannual variations instead of seasonal variations, with nutrient loads and river discharge (turbidity and salinity) being the most prominent features affected by anthropogenic activities and climate change. Over the years, the increasing turbidity and phytoplankton showed that bottom-up effects predominated the aquatic systems. Under the bottom-up effects of eutrophication and turbidity, the phytoplankton communities showed high adaptation that MP and S1 occupied more dominance after 2016, with higher abundance but lower diversity. Moreover, the bottom-up effects further affected the structure of zooplankton communities. The dominance of rotifers filter feeders (RF) decreased over the years while middle copepods and cladocerans filter feeders (MCF) increased, implying a trend of zooplankton toward large size over time. Overall, our result reveals the bottom-up control pattern in the aquatic systems of small urban wetlands. This research provides valuable insights into the dynamics and responses of plankton communities to environmental changes in small urban wetlands, providing valuable information for future conservation efforts. [ABSTRACT FROM AUTHOR]

The main chain of polymer composition in hydrogels is mostly aliphatic and the crosslinking density is usually low, which renders the hydrogels with low mechanical strength. In this work, a kind of thermosetting resin, benzoxazine is used as the starting material to prepare the corresponding hydrogels by one-pot synthesis. The organic gels are firstly formed in dimethylformamide with the aid of catalyst, followed by extraction of water to give the hydrogels. It is revealed that due to the presence of covalent crosslinking and abundant hydrogen bonding, the as-prepared rigid hydrogels show extremely high compressive strength. The hydrogel with 55.8 wt% of water shows yield strength about 20 MPa and sustains compressive strength of 75 MPa (compressive stress of 30 kN, compressive strain of 67 %) without cracking. The hydrogel also show extremely high dielectric constant of 392,000, dielectric loss of 971,000, and ionic conductivity of 1.7 × 10−3 S/m at 100 Hz. Moreover, the responsiveness to pH variation suggests its potential application as smart responsive materials. To show the superiority of preparing functional composite hydrogels using this strategy, electroconductive and magnetic fillers are introduced and the as-prepared composite hydrogels show good electromagnetic shielding performance. [Display omitted] • Robust hydrogels were prepared from thermosetting resin polybenzoxazine at relatively low temperature. • The hydrogel with 55.8 wt% of water showed yield strength about 20 MPa and compressive strength of 75 MPa without cracking. • The high mechanical strength was originated from the combined contribution of chemical bonding and hydrogen bonding. • Easy preparation of functional composites hydrogels by introduction of functional fillers was verified. [ABSTRACT FROM AUTHOR]