Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202509036
Algal-derived phosphorus (P) constitutes a significant fraction in eutrophic lakes, with particulate phosphorus (PP) serving as both a major internal P reservoir and a potential target for P resource recovery. This study proposed a chitosan-coupled electroflotation (CEF) technology for efficient enrichment and recovery of algal-derived P from high-algal water. Using Taihu Lake algae-laden water as the test medium, the effects of chitosan dosage and voltage on the enrichment of different P fractions were systematically evaluated. Results showed that the optimal P enrichment was achieved at a chitosan dosage of 15 mg·L−1, and higher voltages further enhanced the enrichment efficiency. Under optimal conditions, PP accounted for 83.57% of the enriched P, indicating a strong capability for particulate P capture. The mechanism involved chitosan-induced flocculation via charge neutralization and sweep flocculation, while higher voltages increased the positive charge density of chitosan molecules, enhancing charge neutralization and electroflotation. In P release experiments, open conditions significantly promoted the transformation of PP to dissolved P, whereas closed conditions inhibited this process. Additionally, chitosan's antibacterial action and physical retention effectively limited P release. Compared with conventional metal salt coagulants, this method avoids metal ion residues, offering high environmental safety and providing a green and feasible approach for the harmless disposal and resource utilization of algal-derived P in eutrophic lakes.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202511046
To evaluate the carbon footprint differences between the emerging ex-situ remediation facility mode and the conventional on-site remediation mode in China, this study employed the SEFA tool to calculate greenhouse gas (GHG) emissions and energy consumption for four typical remediation scenarios. Results indicate that the carbon emission intensity of solidification/stabilization (S/S) in the remediation facility is 12.00% higher than that of on-site S/S, with unit carbon intensities of 66.74 and 59.59 kgCO2e·m−3, respectively, and total energy consumption 11.90% higher. The soil transport segment in the facility S/S contributes 13% of carbon emissions, being the primary reason for its higher total carbon footprint. Conversely, thermal desorption (TD) in the facility exhibits 11.10% lower carbon emissions than on-site TD, with unit intensities of 269.16 and 302.78 kgCO2e·m−3, and total energy consumption 3.97% lower, mainly due to the utilization of landfill biogas as renewable energy for heat and power generation, while soil transport contributes only 3% of emissions. The reagent segment in S/S and the heat supply segment in TD account for 77%–86% and 70%–72% of total GHG emissions, respectively. The study demonstrates that remediation facilities, leveraging advantages such as landfill biogas, can actively aggregate contaminated soil from surrounding areas for centralized thermal desorption, which is beneficial for regional carbon emission reduction in soil remediation.
Journal of Fuel Chemistry and Technology•2026•DOI: 10.1016/S1872-5813(26)60662-7
Perovskite-type catalysts show promise for CO2 methanation, yet their low-temperature performance and mechanisms remain unclear. Here, a LaNiO3/CeO2 catalyst was synthesized via sol-gel and impregnation. In situ reduction decomposed the perovskite into highly dispersed Ni0 particles (average 12.6 nm) on CeO2, which provided abundant oxygen vacancies (Ce3+/(Ce3++Ce4+) = 9.2%) and weak/moderate basic sites. This synergy enhanced CO2 adsorption and activation. At 200–300 °C, the catalyst achieved ~100% CH4 selectivity and CO2 conversion up to 23.6% at 300 °C. Comparative studies with LaNiO3, LaCeNiO4, Ni/CeO2, and La-Ni/CeO2 revealed that the perovskite pre-structuration and in situ reduction optimize Ni dispersion and metal-support interactions, stabilizing Ni0 and tuning surface basicity and oxygen vacancies. This work provides a design strategy for efficient low-temperature CO2 methanation catalysts.