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The photodegradation of diethyl phthalate (DEP) by UV/H2O2 and UV/TiO2 is studied. The DEP degradation kinetics and multiple crucial factors effecting the clearance of DEP are investigated, including initial DEP concentration ([DEP]0), initial pH values (pH0), UV light intensity, anions (Cl(-), NO(3-), SO4 (2-), HCO3 (-), and CO3 (2-)), cations (Mg(2+), Ca(2+), Mn(2+), and Fe(3+)), and humic acid (HA). Total organic carbon (TOC) removal is tested by two treatments. And, cytotoxicity evolution of DEP degradation intermediates is detected. The relationship between molar ratio ([H2O2]/[DEP] or [TiO2]/[DEP]) and degradation kinetic constant (K) is also studied. And, the cytotoxicity tests of DEP and its degradation intermediates in UV/H2O2 and UV/TiO2 treatments are researched. The DEP removal efficiency of UV/H2O2 treatment is higher than UV/TiO2 treatment. The DEP degradation fitted a pseudo-first-order kinetic pattern under experimental conditions. The K linearly related with molar ratio in UV/H2O2 treatment while nature exponential relationship is observed in the case of UV/TiO2. However, K fitted corresponding trends better in H2O2 treatment than in TiO2 treatment. The Cl(-) is in favor of the DEP degradation in UV/H2O2 treatment; in contrast, it is disadvantageous to the DEP degradation in UV/TiO2 treatment. Other anions are all disadvantageous to the DEP degradation in two treatments. Fe(3+) promotes the degradation rates significantly. And, all other cations in question inhibit the degradation of DEP. HA hinders DEP degradation in two treatments. The intermediates of DEP degradation in UV/TiO2 treatment are less toxic to biological cell than that in UV/H2O2 treatment.

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To realize the selective catalytic reduction of NO at low–medium temperatures and avoid secondary pollution, a highly active catalyst Mn/Co-MOF-74 was synthesized. X-ray diffraction, X-ray photoelectron spectroscopy, thermogravimetric analysis, Brunauer–Emmett–Teller method, and scanning electron microscopy were employed to analyze the physicochemical properties of catalysts with different Mn/Co molar ratios and conjecture about the difference in the catalytic activity. Meanwhile, the effects of the molar ratio of Mn/Co, catalyst dosage, catalyst synthesis conditions, GHSV, and temperature on the NO conversion efficiencies were investigated and found that an optimal NO conversion efficiency of 93.5% was obtained at 200–225 °C. In the end, the stability of Mn/Co-MOF-74 was investigated and found that the catalyst has better sulfur and water resistance, and the NO conversion mechanism was speculated on the basis of characterizations and literature data.