Supported palladium (Pd) catalysts have been extensively studied for water purification applications. However, this technology is primarily challenged by the high cost of Pd and the lack of optimization of catalyst formulations. In this report, we demonstrate a convenient approach to prepare and optimize Pd catalysts for the reduction of toxic oxyanions (bromate, chlorate, and perchlorate). Water-dissolved Na2PdCl4 was quickly adsorbed in the suspension of activated carbon within 5 min and reduced into Pd0 nanoparticles in situ within another 5 min under 1 atm H2 at 20 °C. In terms of both material characterizations and reaction kinetics, the Pd catalysts prepared with the new method show no significant difference from those prepared by the conventional method (involving multiple-step high-temperature procedures) and from benchmark commercial Pd catalysts. With the very simple approach to control, evaluate, and optimize Pd content in the catalyst, we elucidate the relationships among the Pd content, Pd0 particle size, and catalytic activity. We further showcase that the precious metals in previously reported Re–Pd/C and Mo–Pd/C catalysts can be saved up to 80% without sacrificing the activity. The new and convenient catalyst preparation method will significantly enhance the cost-effectiveness of reductive catalysis technologies for water purification.

This study examines the relationship between the labourforce age structure and industry composition in a multiregion and multi-sector framework. Relying on a panel dataset of Chinese provinces, the simultaneous equations model reveals two-way influences between age and industrial structures. Population aging induces a (an) reduced (increased) secondary-sector (tertiary-sector) employment share. The industrial structure then changes the age structure of the local labour force via the migrations of young workers as non-agricultural sectors expand. With an improved Leslie model, we predict a province-level population aging and industry structure trend. Accordingly, municipalities, developed coastal provinces and the three northeastern provinces face greater pressure from population aging and a rapid structural, industrial transformation. Further considerations of the 'two-child policy' via simulation results show that relaxed birth restrictions could slow population aging in some but not all these provinces.

The CCHP system is a reasonable and effective method to improve the current situation of energy use. Capacity allocation is of great significance in improving the performance of the CCHP system. Due to the particularity of chemical enterprises’ production process, the demand for cooling, heating, and power load is also relatively particular, which makes the dynamic loads challenging to be satisfied. Because of the above problems, the structure of the typical CCHP system is improved, embodied in the collocation of multi-stage lithium bromide chiller, and the use of various energy storage devices. Based on the improved ant lion intelligent optimization (ALO) algorithm, the comprehensive evaluation index coupled with energy benefit, economic benefit, and environmental benefit, is taken as the objective function, and the equipment capacity configuration of the CCHP system for chemical enterprises is studied. Considering winter, summer, and transition seasons, the results show that the system is better than the typical CCHP system. The annual cost savings of the new structural system are up to 13%, and the carbon dioxide emissions of the new structural system are reduced by up to 36.39%. The primary energy utilization rate of the new structure system is increased by 18%, and the comprehensive evaluation index also performs better. The optimal index can reach 0.814.

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