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Coking wastewater is one of refractory coal chemical wastewater with a high pollution load，complex organic pollutant composition and strong biological toxicity. The biochemical tail water still retains refractory organic compounds and exhibits a certain level of biological toxicity after conventional physical-chemical and biological treatment. COD fails to meet the discharge standards for pollutants from Emission Standard of Pollutants for Coking Chemical Industry （GB 16171-2012），and further processing is required. The characteristics of residual organic matter and biological toxicity in the biochemical tail water of coking wastewater were analyzed firstly. Subsequently，this review summarized the COD removal efficiency，the change rules of different organic components and biological toxicity in biochemical tail water after application of separation technologies （coagulation，adsorption，membrane filtration），transformation technologies （Fenton，catalytic ozone oxidation，electromagnetic enhanced oxidation technology，persulfate oxidation and electrochemical oxidation） and collaborative processes. It was pointed out that on the basis of understanding the characteristics of the biochemical tail water and biological toxicity transformation rules with various advanced technologies，the collaborative combination process and short process technology would be desired for the efficient treatment and the biological safety.

In order to explore the characteristics of microbial community structure and the potential of pollution reduction and carbon sequestration in petroleum contaminated soil, four typical oil and gas field enterprises in-service well sites of eastern, central, northwestern and southwestern China are selected as the research areas, combined with 16S rRNA high-through put sequencing and bioinformatics technology, the changes of microbial community structure and main environmental driving factors of potential pollution reduction and carbon sequestration in surface soil (0-20 cm) of different oil fields were explored, and the metabolic pathways related to pollution reduction and carbon sequestration were predicted and functionally annotated. The results show that total nutrient and microbial biomass of soil in different oil fields generally exhibit the highest levels in the eastern oilfields, relatively close levels in the southwestern and northwestern oil fields, and the lowest levels in the central oil fields. The dominant bacteria in the soil of the study area were Proteobacteria, Actinobacteriota, Chloroflexi, Bacteroidota and Acidobacteriota. Based on the results of VPA and RDA analysis, MBC, MBN, RubisCO enzyme activity and TPH were the main driving environmental factors affecting the change of microbial community structure in contaminated soil. Among them, TPH (r2=0.67, P=0.001), MBC (r2=0.36, P=0.004 2), MBN (r2=0.74, P=0.003) and RubisCO enzyme activity (r2=0.37, P=0.004 1) were significantly correlated with microbial community structure. The functional annotation results of KEGG database showed that the relative abundance of metabolic pathways related to microbial carbon sequestration in contaminated soils of different oilfields was significantly higher than that of metabolic pathways related to the degradation of organic matter such as petroleum hydrocarbons, and the relative abundance of the above two types of pathways was small among different oilfields. The results are of great significance to support the development of pollution reduction and sink increase technology in petroleum and petrochemical industry under the new situation. [ABSTRACT FROM AUTHOR]

Nucleophilic high molecular-weight organic compounds (HMWOCs) are sensitive to protons (H+) in Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) analysis. A comprehensive evaluation of the diurnal evolution of nucleophilic HMWOCs was performed. HMWOCs aged significantly in daily cycles, accompanied by functionality shifts, particularly oxygenated and reduced nitrogen (CHON and CHN) as well as oxygenated organics. The intensities of high molecular-weight (HMW) oxygenated compounds increased during both daytime and nighttime. The daytime evolution produced more nitrogen-containing compounds with carboxylic group (–COOH) homologues with molecular weights greater than 300, while the nighttime evolution produced mostly small CHON compounds (molecular weights < 300). During evolution, nighttime CHON removals were observed; meanwhile, carboxylation was also identified in CHON groups. The daytime evolution produced significantly more reduced-nitrogen-containing compounds; a day- and nighttime increase in CHN compounds with five members was also observed. This study can provide insights into the aging of less polar organic aerosols. [ABSTRACT FROM AUTHOR]

This study analyzed petroleum-contaminated soils from south and north locations in China to explore the structure, diversity, functional genes and assembly processes of microbial communities' . Compared with soils from south locations, soils from northern regions exhibited elevated pH, total nitrogen (TN), and total petroleum hydrocarbon (TPH) levels. Among these, TN and TPH were the most influential on the microbial community. The dominant phyla for bacteria, archaea, and fungi were Proteobacteria, Thaumarchaeota, and Ascomycota, respectively. Among them, Proteobacteria was strongly correlated with various functional genes including alkB and many aromatics degradation and denitrification genes (r > 0.9, p < 0.01), suggesting that Proteobacteria play an important role in petroleum-contaminated soils. Metabolism in northern regions was more active than that in southern regions. The northern regions showed a pronounced tendency for denitrification, while the southern regions were characterized by acetoclastic methanogenesis. The assembly of microbial communities exhibited regional patterns, the deterministic assembly was more prominent in the northern soils, while the stochastic assembly was evident in the southern soils. Overall, these findings provide a new conceptual framework to understand the biosphere in petroleum-contaminated soil, potentially guiding improved management practices in the environmental remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)