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Summary: Auto‐thermal reforming (ATR) of acetic acid (HAc) is considered as a promising route for hydrogen generation from renewable resources, while oxidation, coking, and sintering need to be addressed for durable catalysts in ATR. In the current work, Zn‐Al hydrotalcite‐derived CoxZnyAlOz catalysts were prepared by co‐precipitation and evaluated in a fixed‐bed tubular quartz continuous‐flow reactor. The Co0.70Zn3.30AlO5.5 ± δ catalyst presented a HAc conversation near 100% and a stable hydrogen yield near 3.01 mol‐H2/mol‐HAc. The characterization results of XRD, H2‐TPR, BET, SEM, XPS, and TG indicated that the hydrotalcite structure was obtained via co‐precipitation method; over the hydrotalcite‐derived mixed oxides, (a) the specific surface area was increased with high dispersion of Co, (b) the phases of ZnO with spinel of ZnAl2O4,CoAl2O4, Co3O4, and ZnCo2O4 were beneficial to improve resistance to coking and oxidation, and (c) the relative stability of Co species over ZnO and spinel phases helps to suppress sintering. Meanwhile, ratio of O/C and temperatures near 0.28 and 650 °C, respectively, were also evaluated and proposed as optimized conditions for hydrogen generation, and the durable Co0.70Zn3.30AlO5.5 ± δ catalyst produced a rate of 114.9 mmol‐H2/s/g‐catalyst in a 15‐hour ATR test, showing promising potential for hydrogen generation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Organic wastewater. • Remove soluble organic matter and particulate matter simultaneously. • The multiple roles in enhanced coagulation-flocculation system were clarified. • The treated products have the potential to be reused as agricultural fertilizers. The high concentration, complexity and refractory of organic pollutants in actual starch wastewater are becoming major obstacles to realizing efficient water purification. Herein, bentonite was selected from four kinds of clay minerals (i.e. kaolin, zeolite, attapulgite and bentonite) as coagulant aids, and chitosan-modified bentonite combined with polyglutamic acid was used for enhanced coagulation treatment for starch wastewater. Among them, bentonite can adsorb soluble pollutants in starch wastewater, chitosan modification can enhance the coagulation effect, and the flocculant of polyglutamic acid is conducive to the removal of particulate matter through bridging effects. The combination of the three can effectively and deeply remove pollutants in starch wastewater. Under the optimal conditions, the removal rates of chemical oxygen demand, total nitrogen, total phosphorus and turbidity can reach 86.2 %, 80.3 %, 52.3 % and 98.2 %, respectively, which are far higher than that of the vast majority of coagulants currently reported. Density functional theory calculation was carried out to reveal the mechanisms for the enhanced coagulation-flocculation system and explained the adsorption and coagulation mechanism, respectively. The electrostatic potential around aluminum in bentonite of 14.248 kcal.mol−1 is more conducive to the adsorption of negatively charged organic pollutants, and that bentonite has lower adsorption energy (-1.43 eV) than chitosan and polyglutamic acid. [ABSTRACT FROM AUTHOR]