Furandicarboxylic acid (FDCA) has been considered as a good precursor, instead of petroleum-derived terephthalate acid (TPA), for producing green polymers such as polyethylene 2,5-furandicarboxylate (PEF). The production of FDCA from biomass or its derived sugars or platform chemicals generally involves chemical, biological and electrochemical methods, while the chemical-catalytic way seems to be the most promising in terms of the yield, reaction rate and product purity. The oxidative production of FDCA from bio-based 5-hydroxymethylfurfural (HMF) has attracted the most attention; it can be carried out by electrochemical, catalytic and non-catalytic processes. In the present work, we have comprehensively reviewed the current progress on the production of FDCA from HMF, primarily focusing on the chemical-catalytic approaches. The most frequently used catalysts for the chemical-catalytic methods are oxides of noble metals but their high cost, poor availability and recycling are the major hindrances to their commercial acceptance. Transition metal oxides are good alternatives but they suffer from relatively low FDCA yield. Electrochemical oxidation of HMF can be a good alternative route for FDCA production with simultaneous H₂ production but the yield and product recovery have to be further improved. Biocatalytic processes can produce FDCA with comparative yields under mild conditions but they can only be operated at low concentrations of HMF with much lower productivity. It is recommended that future works should be focused on, but not limited to, the comprehensive evaluation of different routes in terms of catalyst development and characterizations, process parameters, product yield and purity, as well as economic feasibility. The kinetics and reaction mechanisms of the process also need to be more deeply investigated to guide further process intensification.

The research progress on the production of levulinic acid and its derivatives for fuel additives and chemicals from various sugars and biomass feedstocks have been comprehensively reviewed, focusing on the chemical processes and mechanisms.

The sediment pollution caused by different metals has attracted a great deal of attention because of the toxicity, persistence, and bio-accumulation. This study focuses on heavy metals in the hyporheic sediment of the Weihe River, China. Contamination levels of metals were examined by using “geo-accumulation index, enrichment factor, and contamination factor” while ecological risk of metals were determined by “potential ecological risk and risk index”. The pollutant accumulation of metals ranked as follows: “manganese (Mn) $>$ chromium (Cr) $>$ zinc (Zn) $>$ copper (Cu) $>$ nickel (Ni) $>$ arsenic (As) $>$ lead (Pb)”. The geo-accumulation index identified arsenic as class 1 (uncontaminated to moderate contamination), whereas Cu, Cr, Ni, Zn, Pb, and Mn were classified as class 0 (uncontaminated). According to the enrichment factor, arsenic originated through anthropogenic activities and Cr, Ni, Cu, Zn, and Pb were mainly controlled by natural sources. The contamination factor elucidated that sediments were moderately polluted by (As, Cr, Cu, Zn, Mn, and Pb), whereas Ni slightly contaminated the sediments of the Weihe River. All metals posed a low ecological risk in the study area. The risk index revealed that contribution of arsenic (53.43 %) was higher than half of the total risk.

Globally, natural hazards have become more destructive in recent times because of rapid urban development and exposure. Consequently, significant human life loss, the damage to property and infrastructure, and the collapse of the environment directed the attention of geoscientists to control the consequences and risk management in relation to geo-hazards. In this research, an effort was made to produce a compound map, geo-visualizing the susceptibility of multi-hazards, to select suitable sites for sustainable future development and other economic activities in the region. Muzaffarabad District was chosen as a case research area due to the high magnitude of hydro-meteorological and geological hazards. On the one hand, both selected geo-hazard inventories were developed using the field survey and remote sensing data. The subjective and objective weight of all the causative factors and their classes were calculated using the assembled geospatial techniques, such as the Analytical Hierarchy Process (AHP) and Frequency Ratio (FR) in the Geographic Information System (GIS). The results reveal that the most suitable areas are distributed in the southern and northwestern parts, which can be used for future sustainable development and other economic activities. In contrast, the eastern and western regions, including Muzaffarabad City, are within high and very susceptibility zones. Finally, more than 50% of the land area is located in very low and low susceptibility zones. The validation of the proposed model was checked by using three different techniques: the Receiver Operative Characteristic (ROC) curve, Seed Cell Area Index (SCAI), and Frequency Ratio (FR). Both ROCs, the Success Rate Curve (SRC) and the Predictive Rate Curve (PRC), showed the goodness of fit for both the selected geo-hazards: landslides (81.3%) and floods (93.2%), at 80.1% and 91.7%, respectively. All the validation techniques showed good fitness for both the individual and multi-hazard maps. The proposed model sets a baseline for policy implementation for all the stakeholders to minimize the risk and sustainable future development in areas of high frequent geo-hazards.