Lead removal from water using organic acrylic amine fiber (AAF) and inorganic-organic P-AAF, fixed bed filtration and surface-induced precipitation

Granular porous sorbents were normally used for heavy metals removal from water. To search for the new commercial sorbent and treatment strategy, an organic acrylic amine fiber (AAF) and phosphorus loading inorganic-organic AAF (P-AAF) were prepared and used for lead (Pb) removal from water. A new strategy of inorganic-organic coupling technology was proposed for Pb removal, based on the hypothesis of surface-induced precipitation mechanism. The AAF showed a Pb adsorption capacity of 417 mg/g from the Langmuir fitting, while the column filtration technology was further applied to measure the adsorption edge and applications. Effects of different initial Pb concentrations, hydraulic retention time, and co-existing P were considered in the filtration experiments. The presence of 0.8 mg/L P in water significantly improved the Pb breakthrough point from 15,000 to 41,000 bed volumes of water spiked with 85 µg/L Pb, while the P-AAF fixed bed showed better removal of Pb than AAF SEM/EDX and XRD spectra were employed for determining the surface functional groups and the formation of surface-induced precipitation of pyromorphite (Pb₅(PO₄)₃OH) on AAF. This study verified the application of AAF sorbent for Pb removal and the enhanced effect of coating P on AAF, thus improved our fundamental understanding and application of the surface chemistry process of Pb with P.     

New models for calculating the electrical resistivity of loess affected by moisture content and NaCl concentration

Environmental Science and Pollution Research - Saline loess is an important cause of environmental geo-issues in northwest China. In this research, electrical resistivity of loess with different...     

Improving immobilization efficiency and mechanism analysis of sodium hexametaphosphate on MgO-based cementitious material solidified MSWI FA

Journal of Material Cycles and Waste Management - MgO-based cementitious material (MCM) is a potential green substitute for solidifying municipal solid waste incineration fly ash (MSWI FA). Sodium...     

Investigation of microplastic pollution on paddy fields in Xiangtan City,Southern China

Microplastics (MPs) have become a hot issue of environmental pollution. However, insufficient evidence exists regarding the distributions and fates of MPs in terrestrial environment, especially in farmlands. The distributions of MPs in paddy fields were investigated in Xiangtan City, a typical rice production area in China. The abundance of MPs in paddy seedling raising fields was 3805?±?511 n·kg^?1, which increased by approximately 9 times than that in common paddy fields. Transparent films became the dominant forms due to the huge usage of mulching films, corresponding to that the proportion of polyvinyl chloride (PVC) increased to 17% there. Moreover, an industrial plant nearby also contributed considerably to the MP pollution; the proportion of PVC (33%) in the paddy fields nearby increased to approximately 4 times of common paddy fields, while polyvinyl alcohol (PVA; 13%) used as an important chemical raw material to synthesis in various applications was uniquely detected there. These results highlight the input of MPs from agricultural and industrial activities in farmlands. Their contributions to the MP pollution in farmlands should be continuously investigated.

     

From waste tire to high value-added chemicals: an analytical Py-GC/TOF–MS study

Environmental Science and Pollution Research - A Pyroprobe 5000 pyrolyzer connected to a gas chromatography-time-of-flight mass spectrometry (Py-GC-TOF–MS) was used to analyze the...     

Physicochemical and nutritional features of Gleditsia japonica shell biochar under different pyrolysis conditions

Journal of Material Cycles and Waste Management - This study aimed to investigate the effects of pyrolysis temperature (200–700 °C) and duration (2 h, 4 h) on...