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Clustering the manufacturing industries nearby major river is a common feature globally and can offer significant benefits in terms of productivity improvement. Nonetheless, such clustering also poses extensive and far-reaching environmental burdens on the river. China is implementing a green and low-carbon transformation strategy along the Yangtze and Yellow Rivers, two of the largest rivers in its manufacturing hub. This research examines the following three ways for decoupling economic growth and CO 2 emissions in a typical industrial park located along the Yangtze River, which includes the chemical industry, textile industry, glass manufacturing industry, and automobile manufacturing as pillar industries. First, we use the Tapio decoupling model and Kaya identity to forecast the decoupling paradigm between economic growth and CO 2 emissions in the park by 2030 in response to policy interventions. Second, 10 two-digit level industries (TDLIs) with high energy-resource consumption and CO 2 emissions in the manufacturing sector are evaluated. Third, a model is developed to determine the most appropriate approach for modifying the 10 TDLIs' structures under different scenario analysis. The main findings are as follows. It is expected that the parks could achieve a relative decoupling around 2028 and 2029 under policy interventions. In addition, tailored policies for industries with high economic output and low CO 2 emissions are proposed, while their opposites are also. Lastly, the optimal way for the park to decouple economic development and CO 2 emissions is to simultaneously adjust its industrial structure and upgrade its energy facilities. This would result in a 31% reduction in CO 2 emissions with positive effects on the economy and continuous upgrading of the industrial structure of the park. This study will play an important role in the green transformation of China's manufacturing clusters located along the Yangtze and the Yellow Rivers and will also have implications for other similar manufacturing clusters. • Reduction of carbon dioxide (CO 2) in industrial parks near big rivers is revealed. • A 3-model integrated method decouples economic growth from CO 2 emissions in parks. • CO 2 emissions quota, economic growth, and adjustment smoothness are contemplated. • Industrial structure adjustment boosts economic growth and reduces CO 2 emissions. [ABSTRACT FROM AUTHOR]

The controllability of composition and structure of layered double hydroxide (LDH) is one of the important grounds for their widespread use in removing hexavalent chromium (Cr(VI)) from the environment. In this study, single-layer LDHs were successfully produced through an ultrasound-assisted process in the presence of formamide and characterized by X-Ray diffraction (XRD), scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), atomic force microscope (AFM) and surface energy. Then LDHs were utilized to remove Cr(VI) in solutions, of which the results demonstrated that delaminated MgAl in formamide with ultrasound (F-U-MgAl) had the highest adsorption efficiency, and the adsorption equilibrium was reached in the first 1 min, with a removal rate of 100%. While the removal rate of Cr(VI) by delaminated MgAl without ultrasound (F-MgAl) and MgAl were only 77% and 12% after 60 min. Based on the XRD patterns and SEM images of samples before and after adsorption, the adsorption mechanisms of F-U-MgAl included anion exchange, surface adsorption and electrostatic attraction. The effects of initial pH, dosage, initial concentration, coexisting anions, and HA were also investigated. In addition, the adsorption in Cr(VI)-containing soil by LDHs was considered, and the results indicated that the single-layer LDHs had a broad application prospect in soil remediation. Besides that, we had also verified the above conclusion through the phytotoxicology tests. [Display omitted] • Delaminated LDHs were synthesized and characterized. • Delaminated LDHs are used in the remediation of Cr(VI)-contaminated water and soil. • The adsorption effect of delaminated LDHs were better than original LDHs. • Delaminated LDHs can reduce the phytotoxicity of Cr(VI). [ABSTRACT FROM AUTHOR]

Nowadays, reducing the environmental impact of biorefinery is a common concern of scholars. life cycle assessment (LCA) is a widely used method to evaluate the environmental impact of biorefinery. Considering the lack of a latest review on the progress and existing problems related to biorefinery based on LCA studies, this paper carried out a systematic review of the evaluation of environmental impact of biorefinery based on LCA, and proposed the development strategies for waste biorefineries by targeting literature on LCA methods. After finding out the imperfections existing in the current researches, the paper then constructed a comprehensive and systematic biorefinery framework with a standard LCA employed as a reference template for following researches. 92 peer-reviewed articles published in Web of Science, Springer and Scopus from 2015 to 2019 with LCA and biorefinery as the keywords were considered. The key findings are as follows: (1) Agricultural waste and industrial residues are the top two feedstocks widely employed, accounting for 32.61% and 29.35% respectively; (2) the primary data is scarce. The foreground data of LCA is 56.52% from the researches of other scholars; (3) the LCA methods are not standardized. 30.26% and 18.42% have unclear system boundaries and functional units; and (4) there is a lack of estimating the influences of various uncontrollable external factors in the biorefinery process. Furthermore, the review highlighted and discussed the defects of biorefineries, a robust LCA template that can be used for evaluating the environmental impact of biorefinery was constructed, taking algae biorefinery as an example. Image 1 • 92 research articles on LCA and biorefinery are reviewed to update the latest progress. • Major issues on employing life cycle assessment for facilitating sustainable biorefinery are uncovered. • The environmental impacts of widely used biorefinery feedstocks and technologies are compared. • Recommendations for future biorefinery-driven LCA are proposed from five aspects. • A demonstration model on the biorefineries with LCA was exemplified. [ABSTRACT FROM AUTHOR]

Soil is commonly polluted by chromium, and layered double hydroxides (LDHs) are widely used for chromium removal due to their strong adsorption capacity and the unique properties of their delaminated products. In this study, delaminated LDHs (S–Mg-LDH and S–Ca-LDH) and their original LDHs were used to remediate Cr(VI)-contaminated soil. A series of characterizations confirmed the successful synthesis of delaminated LDHs whose sheet structure was thinner with a greater surface energy than the original LDHs. The remediation results indicated that delaminated LDHs could more efficiently immobilize Cr(VI) in soil. The immobilization rate of S–Mg-LDH was 64.32%, while Mg-LDH was only 8.09%. However, at low dosages, the efficiency of S–Ca-LDH was 28.1% while Ca-LDH was 5.16%, but they had similar effects at high doses. Moreover, soil pH had little effect on their removal efficiencies. The toxicity characteristic leaching procedure (TCLP) results showed that the leaching of Cr(VI) in soil after treatment with S–Mg-LDH, S–Ca-LDH, Mg-LDH, and Ca-LDH was reduced by 75.43%, 72.43%, 86.55%, and 75.90%, respectively. The phytotoxicity tests of soil treated by S–Mg-LDH and S–Ca-LDH revealed that they effectively reduced the toxicity of chromium and lowered its bioaccumulation. Overall, this study confirms the feasibility of delaminated LDHs for Cr(VI) immobilization in soils. Image 1 • Delaminated LDHs were synthesized and characterized. • Delaminated LDHs and LDHs are used in the remediation of Cr-contaminated soil. • The immobilization effect of delaminated LDHs were better than original LDHs. • Delaminated LDHs can reduce the leachability and phytotoxicity of Cr. [ABSTRACT FROM AUTHOR]