Study on biodegradation process of lignin by FTIR and DSC

The biodegradation process of lignin by Penicillium simplicissimum was studied to reveal the lignin biodegradation mechanisms. The biodegradation products of lignin were detected using Fourier transform infrared spectroscopy (FTIR), UV–Vis spectrophotometer, different scanning calorimeter (DSC), and stereoscopic microscope. The analysis of FTIR spectrum showed the cleavage of various ether linkages (1,365 and 1,110 cm^?1), oxidation, and demethylation (2,847 cm^?1) by comparing the different peak values in the corresponding curve of each sample. Moreover, the differences (T_m and ΔH_m values) between the DSC curves indirectly verified the FTIR analysis of biodegradation process. In addition, the effects of adding hydrogen peroxide (H₂O₂) to lignin biodegradation process were analyzed, which indicated that H₂O₂ could accelerate the secretion of the MnP and LiP and improve the enzymes activity. What is more, lignin peroxidase and manganese peroxidase catalyzed the lignin degradation effectively only when H₂O₂ was presented.     

Degradation of 3,3′-iminobis-propanenitrile in aqueous solution by Fe0/GAC micro-electrolysis system

The degradation of 3,3′-iminobis-propanenitrile was investigated using the Fe⁰/GAC micro-electrolysis system. Effects of influent pH value, Fe⁰/GAC ratio and granular activated carbon (GAC) adsorption on the removal efficiency of the pollutant were studied in the Fe⁰/GAC micro-electrolysis system. The degradation of 3,3′-iminobis-propanenitrile was affected by influent pH, and a decrease of the influent pH values from 8.0 to 4.0 led to the increase of degradation efficiency. Granular activated carbon was added as cathode to form macroscopic galvanic cells between Fe⁰ and GAC and enhance the current efficiency of the Fe⁰/GAC micro-electrolysis system. The GAC could only adsorb the pollutant and provide buffer capacity for the Fe⁰/GAC micro-electrolysis system, and the macroscopic galvanic cells of the Fe⁰/GAC micro-electrolysis system played a leading role in degradation of 3,3′-iminobis-propanenitrile. With the analysis of the degradation products with GC–MS, possible reaction pathway for the degradation of 3,3′-iminobis-propanenitrile by the Fe⁰/GAC micro-electrolysis system was suggested.     

Duo-molecularly imprinted polymer-coated magnetic particles for class-selective removal of endocrine-disrupting compounds from aqueous environment

The removal of steroid and phenolic endocrine-disrupting compounds (EDCs) from an aqueous environment was investigated using magnetic particles encapsulated by a duo-molecularly imprinted polymer (duo-MIP). The effect of environmental variables on the binding efficiency was studied. Experimental results showed that the amount of EDCs adsorbed was neither affected by up to 10.0 mM NaCl nor significantly interfered by up to 10.0 mg/L humic acid. Negligible influence was observed from pH 3.3 to pH 6.8, but a decrease started at pH 9. Freundlich isotherm parameters indicated binding capacities in the order of DES?>?E2?～?E1?>?BPA. The applicability of class-selective removal was verified using river water samples spiked with these EDCs at 10 μg/L; the binding efficiencies were 90, 90, 88, and 98 % for estrone (E1), 17β-estradiol (E2), bisphenol A (BPA), and diethylstilbestrol (DES), respectively. A reuse investigation verified constant binding capacities exhibiting <2 % reduction after seven cycles of regeneration.     

The treatment of black-odorous water using tower bipolar electro-flocculation including the removal of phosphorus,turbidity, sulfion,and oxygen enrichment

• An innovative bubble column tower BPE was designed to treat the black-odorous water. • PO₄³⁻, S²⁻ and turbidity were removed, and dissolved oxygen was enriched in the BPE. • An aluminum bipolar electrode gave the best oxygen enrichment and pollutant removal. • Changes of microorganisms confirmed the improvement in water quality achieved. The large amount of municipal wastewater discharged into urban rivers sometimes exceeds the rivers’ self-purification capacity leading to black-odorous polluted water. Electro-flocculation has emerged as a powerful remediation technology. Electro-flocculation in a bubble column tower with a bipolar electrode (BPE) was tested in an attempt to overcome the high resistance and weak gas-floatation observed with a monopolar electrode (MPE) in treating such water. The BPE reactor tested had a Ti/Ta₂O₅-IrO₂ anode and a graphite cathode with an iron or aluminum bipolar electrode suspended between them. It was tested for its ability to reduce turbidity, phosphate and sulphion and to increase the concentration of dissolved oxygen. The inclusion of the bipolar electrode was found to distinctly improved the system’s conductivity. The system’s electro-flocculation and electrical floatation removed turbidity, phosphate and sulphion completely, and the dissolved oxygen level improved from 0.29 to 6.28 mg/L. An aluminum bipolar electrode performed better than an iron one. Changes in the structure of the microbial community confirmed a significant improvement in water quality.     

A comprehensive review of the circulation of microplastics in aquatic ecosystem using scientometric method

Environmental Science and Pollution Research - Nowadays, the extensive application of microplastics (MPs) has led to the gradual accumulation of toxicity in aquatic environment and caused potential...     

Bifunctional catalysts for heterogeneous electro-Fenton processes: a review

Environmental Chemistry Letters - Fenton processes allow to degrade and mineralize toxic organic contaminants, yet classical Fenton processes require continuously adding hydrogen peroxide and...     

Effectiveness of predicting the spatial distributions of target contaminants of a coking plant based on their related pollutants

Environmental Science and Pollution Research - The prediction accuracy of the spatial distribution of soil pollutants at a site is relatively low. Related pollutants can be used as auxiliary...     

Sustainable ternary cement blends with high-volume ground granulated blast furnace slag–fly ash

Environment, Development and Sustainability - Coal fly ash and granulated ground blast furnace slag (GGBS) are more widely used as supplementary cementitious materials in cement production. This...     

Can environmental regulations break down domestic market segmentation? Evidence from China

Environmental Science and Pollution Research - While local protectionism and market segmentation owing to fiscal decentralization are not conducive to broad economic development, they may be...