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Poultry manure is a significant source of ammonia (NH 3) emissions, which not only poses detrimental impacts on human well-being and the ecological system, but also leads to economic losses in the agricultural industry. Herein, we modified corn straw (CS) with 1 wt% Pt/TiO 2 catalysts using a low-temperature partial-oxidation technology to mitigate NH 3 emissions from poultry manure. It was found that Pt/TiO 2 can enable exothermic processes to occur at lower temperatures by reducing the activation energy. Under optimal modification conditions of 220 °C, the NH 3 uptakes of modified CS samples were markedly greater compared to those of the original CS. Addition of 20–50% modified CS to poultry manure resulted in significant reductions of 54.1–98.6% in NH 3 emissions compared to the control. Mechanistic studies indicate that NH 3 adsorption on the modified CS is mainly driven by the presence of acidic and alkaline functional groups, while surface area and pore structure have a negligible effect. XPS combined with NH 3 -TPD reveals that the formation of amide and amine bonds contributes to the excellent stability of adsorbed NH 3. H 2 -TPR, O 2 -TPD, and d -band theory suggest that strong metal-support interactions between Pt and TiO 2 could be particularly crucial in catalyzing CS modification. This study proposes an environmentally sustainable and economically viable solution for abating NH 3 emissions from poultry manure, thereby addressing crucial environmental and economic concerns in the agricultural sector. [Display omitted] • Pt/TiO 2 aids low-temperature exothermic processes for CS modification. • NH 3 adsorption on CS is driven by acidic and alkaline groups. • Amide/amine bonds contribute to NH 3 adsorption stability. • Metal-support interactions in Pt/TiO 2 could be crucial for CS modification. [ABSTRACT FROM AUTHOR]

Energy and water resources are closely linked in electric power systems, and the application of low-carbon technologies further affects electricity generation and water consumption in those systems. The holistic optimization of electric power systems, including generation and decarbonization processes, is necessary. Few studies have considered the uncertainty associated with the application of low-carbon technologies in electric power systems optimization from an energy-water nexus perspective. To fill such a gap, this study developed a simulation-based low-carbon energy structure optimization model to address the uncertainty in power systems with low-carbon technologies and generate electricity generation plans. Specifically, LMDI, STIRPAT and grey model were integrated to simulate the carbon emissions from the electric power systems under different socio-economic development levels. Furthermore, a copula-based chance-constrained interval mixed-integer programming model was proposed to quantify the energy-water nexus as the joint violation risk and generate risk-based low-carbon generation schemes. The model was applied to support the management of electric power systems in the Pearl River Delta of China. Results indicate that, the optimized plans could mitigate CO 2 emission by up to 37.93% over 15 years. Under all scenarios, more low-carbon power conversion facilities would be established. The application of carbon capture and storage would increase energy and water consumption by up to [0.24, 7.35] × 106 tce and [0.16, 1.12] × 108 m3, respectively. The optimization of the energy structure based on energy-water joint violation risk could reduce the water utilization rate and the carbon emission rate by up to 0.38 m3/104 kWh and 0.04 ton-CO 2 /104 kWh, respectively. • A simulation-based inexact optimization model for power systems planning. • A low-carbon electric power system was optimized under uncertainty. • CO 2 emissions under different socio-economic development levels were simulated. • The scale of generation facilities was optimized under different risk combinations. [ABSTRACT FROM AUTHOR]

Turning agricultural waste into effective remediation materials is a highly promising approach for reducing in-field crop burning and promoting affordable wastewater treatment. This comparative study aims to identify active adsorption sites for methylene blue (MB), crystal violet (CV), and cadmium (Cd) as model pollutants on wheat straw materials modified by a thermal partial-oxidation process. The optimal modification temperature was found to be 160–180 °C for MB and CV adsorption, which is much lower than that of Cd(II) at 220–240 °C. A strong linear correlation exits between total surface group concentrations and Cd(II) uptake, indicating that both acidic and basic functional groups are favourable adsorption sites of Cd(II). By contrast, basic groups generated at higher modification temperatures might have adverse effects on MB and CV adsorption. These results provided mechanistic insights and predictive approach into reuse of agricultural waste for environmental remediation. [Display omitted] • A thermal modification method was applied to wheat straw materials. • Optimal modification temperatures strongly depend on type of pollutants. • Both acidic and basic groups are favourable adsorption sites for Cd(II). • Basic functional groups might have adverse effects on MB and CV adsorption. • This work provides insights to reuse of agricultural waste and environment clean-up. [ABSTRACT FROM AUTHOR]

The removal of organic pollutants in water environments and the resource utilization of solid waste are two pressing issues around the world. Facing the increasing pollution induced by discharge of mining effluents containing sodium isopropyl xanthate (SIPX), in this work, municipal solid waste incineration fly ash (MSWI FA) was pretreated by hydrothermal method to produce stabilized FA, which was then innovatively used as support for the construction of FA/TiO 2 /BiOCl nanocomposite (FTB) with promoted photocatalytic activity under visible light and natural sunlight. When the content of FA was 20 wt% and the mass ratio of TiO 2 to BiOCl was 4:6, a remarkable performance for the optimal FTB (20-FTB-2) was achieved. Characterizations demonstrated that TiO 2 and BiOCl uniformly dispersed on FA contributing to high surface area and broad light adsorption of FTB, which exhibits excellent adsorption capacity and light response ability. Build in electric field formed in the interface of TiO 2 /BiOCl heterojunction revealed by density functional theory calculations accelerated the separation of photoinduced e− and h+, leading to high efficiency for SIPX degradation. The synergetic effect combined with adsorption and photocatalytic degradation endowed 20-FTB-2 superior SIPX removal efficiency over 99% within 30 min under visible light and natural sunlight irradiation. The photocatalytic degradation pathways of SIPX were determined through theoretical calculations and characterizations, and the toxic byproduct CS 2 was effectively eliminated through oxidation of •O 2 −. For 20-FTB-2, reusability of photocatalyst was showed by cycle tests, also the concentrations of main heavy metals (Pb, Zn, Cu, Cr, and Cd) in the liquid phases released during photocatalyst preparation process (< 1 mg/L) and photodegradation process (< 8.5 μg/L) proved the satisfactory stability with low toxicity. This work proposed a novel strategy to develop efficient and stable support-based photocatalysts by utilizing MSWI FA and realize its resource utilization. [Display omitted] • Stabilized FA supported the construction of FA/TiO 2 /BiOCl heterojunction composite. • Optimized 20-FTB-2 exhibited superior photocatalytic degradation of SIPX (>99.9%). • Heavy metals in FTB leached out hardly during photocatalytic degradation process. • Fly ash-supported photocatalyst enhanced adsorption and photocatalytic capability. • Detailed photocatalytic mechanism and degradation pathway of SIPX were proposed. [ABSTRACT FROM AUTHOR]