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[Display omitted] • Fe/NC catalyst shows good activity and stability for cleaving C-O bonds in lignite. • Fe-N and Fe/Fe 3 C species in the catalyst were crucial to the catalytic activity. • Active hydrogen species were hydrogen radicals generated from H 2 and isopropanol. • The hydrocracking products have higher H/C ratio and heating values than lignite. • Catalytic hydrocracking promoted producing phenols via the cleavage of C-O bonds. Cleaving C-O bridged bonds of lignite via catalytic hydrocracking (CHC) is an effective method to produce chemicals and clean fuels. Herein, a nitrogen-doped carbon supported Fe catalyst was developed by using a one-pot method for CHC of Xilinguole lignite (XL) and its related model compounds. The doped nitrogen enhanced the interaction between Fe and N species to form Fe-N sites and favored forming smaller Fe/Fe 3 C nanocrystals, which played a crucial role in CHC performance. Toluene and phenol were produced from CHC of benzyl phenyl ether (BPE) with high yield and selectivity at 250 °C over the optimal catalyst with 4% Fe, without hydrogenation products. The Fe-based catalyst activated both H 2 and isopropanol to generate hydrogen radicals for cleaving C-O bridged bonds. The CHC of XL under different temperature and time showed that the yields of oil, asphaltene and preasphaltene were obviously promoted under 325 °C, 1 MPa, and 6 h, and they had much higher H/C ratio but remarkably lower O/C ratio, resulting in much higher heating values (28.19–36.90 MJ/kg) than XL. Phenols were the major group component with relative content of 53.6 wt% in oil from CHC, and the asphaltene and preasphaltene from CHC had obviously lower molecular weights, which could attributed to depolymerization of C-O bridged bonds in the XL macromolecular structures over the catalyst. [ABSTRACT FROM AUTHOR]

• A particulate loading and active regeneration cycle of the diesel particulate filter were performed on a burner. • Most ash-bridges were observed in the middle region of the diesel particulate filter channel. • Using Ca-based or Mg-based additive lubricants is beneficial to reduce the ash-bridge deposition. • When the blockage rate is greater than about 70%, the channels near the ash bridge are destroyed. Diesel particulate filter (DPF), an important after-treatment system, is widely used to trap particulates from diesel engines. After many active regenerations of the DPF, non-volatile ash may form an ash bridge phenomenon in the DPF channel. This paper studies the effects of lubricant components on ash-bridge deposition characteristics in the DPF. Four test lubricants were prepared based on the CK-4 standard lubricant with four different additives (Ca-based, Mg-based, compound, and Zinc dialkyl dithiophosphate (ZDDP) additives), which were separately and proportionately blended into diesel fuel to form four different fuels. A particulate loading and active regeneration cycle of the DPF with those fuels were performed on a burner. The results show that mid-channel ash deposits (MCD) and the ash-bridge phenomenon were observed in the DPF with all four fuels, and the ash-bridge was mainly located in the middle region of the DPF channel. Mg-based or ZDDP additives can improve the ash-channel ratio (A: C) of the MCD. Ca- or Mg-based additives can reduce the distribution density of ash bridges and avoid sintering of DPF. Different shapes of ash bridges will cause different blockage rates in the DPF channel. When the blockage rate of the DPF channel is greater than about 70 %, DPF channels near the ash bridge are destroyed. [ABSTRACT FROM AUTHOR]