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Graphical abstract Preparation of glycerol carbonate from glycerol and CO 2 over polymer catalysts functionalized with ionic liquid groups. Highlights • Several polymer catalysts were prepared and applied for the preparation of glycerol carbonate. • The polymer functionalized with ionic liquid groups presented the best catalytic performance. • Glycerol served as both reactant and co-catalyst during the reaction. • The catalyst was highly recyclable. Abstract In the present work, several DVB-based polymer catalysts were prepared and used for the synthesis of glycerol carbonate (GC) from glycerol carbonylation with carbon dioxide (CO 2). Propylene oxide (PO) was introduced as a coupling reagent into the reaction to disturb the thermodynamics limitation. The characterization results confirmed the successful preparation of the functionalized polymer catalysts. P-DVB-(vIm-BuBr) showed the best catalytic performance among the prepared polymers. The high catalytic activity of P-DVB-(vIm-BuBr) was attributed to the presence of ionic liquid groups in the structure of the polymer. In addition, the preparation method had a significant influence on the catalytic activity of the polymer. Functionalization of the monomer with n-butyl bromide before polymerization could increase the content of ionic liquid groups of the polymer catalysts. During the reaction process, glycerol served not only as a reactant, but also as a co-catalyst to facilitate the coupling of PO with CO 2. P-DVB-(vIm-BuBr) achieved PO conversions as high as 96% and GC yields of 81% under optimal reaction conditions. The catalyst was highly recyclable and maintained its catalytic activity after five reaction cycles. [ABSTRACT FROM AUTHOR]

In the present work, melem based catalysts with various functional groups were developed by the modification of melem oligomers and tested for the chemical fixation of CO 2 into cyclic carbonates. The characterization of these catalysts, by means of SEM, BET, XRD, IR, TG and XPS, verified the functional groups are successfully incorporated into the melem oligomers structure. Activity test demonstrated that melem oligomers grafted with both hydroxyl and quaternary ammonium groups (MOSB) presented the best catalytic performance. A propylene oxide conversion of 97.4% and propylene carbonate selectivity of 97.8% were obtained under the optimal reaction conditions. The simultaneous existence of edge defects, hydroxyl groups and quaternary ammonium groups in the structure of the catalyst are responsible for the high performance of MOSB. These three groups synergistically catalyzed the chemical fixation of CO 2 to proceed with high efficiency. Moreover, moderate yield could still be obtained after five cycles. A possible reaction mechanism was proposed for the cycloaddition of CO 2 with epoxides to form cyclic carbonates. [ABSTRACT FROM AUTHOR]

In this study, an effective method of mechanical vapor recompression coupling Organic Rankine Cycle process is introduced to purify crude biodiesel obtained by solid base-catalyzed transesterification. Mechanical vapor recompression is used for recovering the waste heat of the methanol, while the Organic Rankine Cycle is applied for converting the waste heat of biodiesel into electric energy. Pinch technology is proposed to guide the coupling of mechanical vapor recompression and Organic Rankine Cycle process, the electric energy and waste heat generated by Organic Rankine Cycle are supplied to the mechanical vapor recompression system. Compared with conventional purification process, the total annual cost of proposed process decreases by 55.40% and the greenhouse gas emissions decrease by 76.31% for CO 2 , 76.41% for SO 2 , and 76.42% for NO x , respectively. In addition, the parameters of the proposed process are optimized to achieve a coefficient of performance of 16.03 for mechanical vapor recompression and 14.06% thermal efficiency for Organic Rankine Cycle. • An energy-saving biodiesel purification process was proposed. • Pinch technology was used to guide the process design. • The proposed process reduced exergy destruction. • The proposed process had economic and environmental advantages. [ABSTRACT FROM AUTHOR]

Cyanobacteria were catalytically pyrolyzed over Mg-Al layered double oxide/ZSM-5 composites (MgAl-LDO/ZSM-5) to produce bio-oil. MgAl-LDO/ZSM-5 with a Mg/Al molar ratio of four was proved to be the best catalyst. Under the optima condition that the final temperature was 823 K, heating rate was 10 K/min and catalyst/algae mass ratio was 0.75, a maximum yield of liquid (41.1%) was achieved at 823 K with a heating rate of 10 K/min and a catalyst/algae mass ratio of 0.75, which was much higher than the one obtained without catalyst. The element analysis results proved that this bio-oil had much lower O/C molar ratio and higher HHV. The GC–MS results showed that the bio-oil had less nitrogenous compounds. MgAl4-LDO/ZSM-5 was proved to be an applicable and effective catalyst to obtain bio-oil from catalytic pyrolysis of water-blooming algae. [ABSTRACT FROM AUTHOR]

In this study, Ca–Mg–Al hydrotalcite was deposited on the inert honeycomb ceramic surface as a second carrier and KF was loaded on the support as an active component. The KF/Ca–Mg–Al hydrotalcite/honeycomb ceramic monolithic catalyst was packed in the membrane reactor for biodiesel production from the transesterification between soybean oil and methanol. The central composite design (CCD) of response surface methodology (RSM) was employed to investigate the effects of reaction temperature, catalyst amount and circulation velocity on the production of biodiesel. A quadratic model was developed to navigate the design space. The optimum condition for the highest biodiesel yield was obtained by the assistance of the model. The catalyst showed a reasonable efficiency and reusability for coupling the monolithic catalyzed transesterification and membrane separation in the membrane reactor. [ABSTRACT FROM AUTHOR]

During transesterification process in the fixed-bed reactor, traditional heterogeneous catalyst cannot stand the high pressure drop and would easily breaks at the reactor bottom thus blocking the outlets. KF/γ-Al 2 O 3 /honeycomb ceramic (HC) monolithic catalyst which was prepared in this research can be utilized because of its thermal and mechanical stability. γ-Al 2 O 3 was deposited on the inert HC surface as a second carrier and KF acted as an active component. Loading ratio and loading intensity were both examined in order to select for catalyst with best catalytic performance. Optima reaction condition in the fixed-bed reactor was studied by investigating the effect of residence time, methanol/oil molar ratio and reaction temperature on oil conversion. Experiment results indicated that when the residence time was 33 min, the methanol/oil molar ratio was 18:1, the reaction temperature was 140 °C and with saturated vapor pressure, oil conversion could exceed 96%. X-ray diffraction (XRD) and scanning electron microscope (SEM) indicated that the KF/γ-Al 2 O 3 /HC monolithic catalyst shared the same alkaline catalytic centers identical to KF/γ-Al 2 O 3 . [ABSTRACT FROM AUTHOR]

Highlights: [•] Solid acid catalysis and membrane separation was coupled for biodiesel production. [•] PTSA/MCM-41 was used as a catalyst for biodiesel production in a membrane reactor. [•] Box–Behnken design was employed to analyze and optimize the process. [ABSTRACT FROM AUTHOR]

Abstract: The evaluation of the failure probability and safety level of occupant evacuation is of extreme importance. The safety level of occupant evacuation is expressed by the margin of escape time. Three traditional methods for solving the reliability index are introduced and an optimization method is proposed in this study. Comparisons between the optimization method and the traditional methods are carried out. Since occupant evacuation is affected by various random parameters, it is necessary to analyze the importance of each variable in comparison with the others in occupant safety evacuation. A methodology is presented to classify the significant and insignificant random variables using sensitivity analysis. Finally, the successful application in a case study suggests that these methodologies are suitable and reliable for the reliability analysis of occupant safety evacuation in public assembly occupancies. [Copyright &y& Elsevier]

Abstract: The solid base catalyst KF/Ca–Al hydrotalcite was obtained from Ca–Al layered double hydroxides and successfully used in the transesterification of methanol with palm oil to produce biodiesel. With the load of KF, the activity of Ca–Al mixed-oxides had been improved much. For the mass ratio 80wt.%(KF·6H2O to Ca–Al mixed-oxides) catalyst, under the optimal condition: 338K, catalyst amount 5%(wt./wt. oil) and methanol/oil molar ratio 12:1, after 5h reaction, the fatty acid methyl esters yield could reach 97.98%; for the mass ratio 100wt.%(KF·6H2O to Ca–Al mixed-oxides) ones, under the same reaction condition, only needed 3h to get the FAME yield of 99.74%, and even only reacted 1h, the FAME yield could obtain 97.14%. [Copyright &y& Elsevier]

Electrocatalytic reduction of CO 2 affords a potential way to mitigate the greenhouse effect and fuel crisis. In this work, we compared highly-dispersed CuO nanocomposites and Cu–Cu 2 O nanocomposites which all derived from Cu x Al-LDH for CO 2 electrochemical reduction. The Cu–Cu 2 O based nanocomposites obtained through the restoration strategies still retain its layered structure, simultaneously increasing dual Cu–Cu 2 O active sites, which exhibit excellent performance in selective reduction of CO 2 to C 2 H 4. The Cu 5 Al-ER obtained through in-situ electrochemical reduction is modified by bulk phase, which can regulate active species, increase surface active sites, enhance C–C coupling. Meanwhile, the electrochemical strategy offers numerous benefits, including gentle conditions, adjustable monitoring, exceptional efficiency and adaptability. We have confirmed that cost-effective Cu–Cu 2 O based nanocomposite derived from Cu 5 Al-LDH can effectively promote C–C coupling during electrochemical CO 2 conversion and improve FE C2H4. The FE C2H4 of Cu 5 Al-ER reaches 36% at −1.2 V vs. RHE. And the current density reaches −172 mA·cm−2 at −1.6 V vs. RHE. The results showed that compared to Cu 5 Al-LDO, the FE C2H4 of Cu 5 Al-ER increased by 2.6 times. In addition, Cu 5 Al-ER exhibits excellent stability during the 12 hours CO 2 catalytic reduction process. • Controllable dual Cu–Cu 2 O sites were derived from cost-effective Cu x Al-LDH. • Cu 5 Al-HR and Cu 5 Al-ER still retain its layered structure. • The copper ratio and reduction method have an impact on the FE C2H4. • Cu 5 Al-ER exhibited superior catalytic performance in CO 2 RR compared to Cu 5 Al-HR. [ABSTRACT FROM AUTHOR]

Liquid phase and one-step reaction for furfural (FFR) hydrogenated to tetrahydrofurfuryl alcohol (THFA) was conducted by employing noble metal-absence and toxicity-free, bimetallic Ni-Co catalysts. The bimetallic Ni-Co catalysts with different molar ratio of Ni to Co and two monometallic catalysts (Ni, Co) were synthesized by conventional incipient-wetness impregnation method with short channeled SBA-15 as support. Among these catalysts, highly selective hydrogenation of FFR to THFA was attained over Ni-Co/SBA-15 catalysts. The impact of molar ratio of Ni/Co was studied with a fixed Ni loading (10 wt %) in bare support. The samples were characterized by N 2 sorption, XRD, XPS, H 2 -TPR, SEM, TEM and CO chemisorption. The results confirmed that the reducibility of Ni-catalysts can be improved by incorporating Co metal and revealed that appropriate amount of spinel NiCo 2 O 4 oxides is favorable to uniform and high dispersion of Ni 0 and CoO over short channeled SBA-15, which would be benefit for the catalytic performance. For catalytic activity investigation, other four mesoporous SiO 2 materials (MCM-41, MCM-4, MCF-2 and common SBA-15) were employed as supports to investigate the effect on the hydrogenation of FFR and the reaction parameters including the reaction temperature, initial of H 2 pressure, reaction time and the reusability of the catalysts were also studied. 100% of FFR conversion and 92.1% of THFA selectivity were achieved at 90 °C, 50 bar of initial H 2 and 2.0 h over catalyst Ni-Co/SBA-15 when the molar ratio of Ni to Co was 0.67. [ABSTRACT FROM AUTHOR]

Methanol and dimethyl carbonate (DMC) mixture is present in the industrial manufacturing process of DMC, which is made from the catalytic oxidative carbonylation of methanol. The separation of methanol and DMC is important but difficult due to the formation of an azeotropic mixture. This work has been focused on a study of phosphoric-based ionic liquids (ILs) as green solvents for the separation of methanol and DMC in the extraction process. The knowledge of liquid–liquid equilibrium (LLE) of this mixture is essential for the design of the extraction separation process. For this reason, LLE data for the ternary systems {methanol + DMC + 1-methyl-3-methylimidazolium dimethylphosphate ([MMIM][DMP])} and {methanol + DMC + 1-ethyl-3-methylimidazolium diethylphosphate ([EMIM][DEP])} were measured at T = (298.2 and 313.2) K and atmospheric pressure. The solute distribution ratio and selectivity of the methanol, derived from the tie-lines data, were calculated and analyzed in order to evaluate the capacity of the studied ILs as solvents in liquid extraction process. The experimental results show that the values of selectivity for the studied ILs follow this order: [MMIM][DMP] > [EMIM][DEP]. Finally, the experimental LLE data for the studied ternary systems were compared with the calculated values obtained by means of the non-random two liquid (NRTL) model. The NRTL model was verified to accurately correlate the experimental LLE data. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of catalysts derived from silicotungstic acid (SiW) intercalated with CuZnFe hydrotalcite-like compounds (HTLCs). • The introduction of SiW significantly improved the selectivity towards 1,3-PDO, owing to the increased number of Brønsted acid sites. • The catalyst intercalating 30 wt.% SiW showed the highest selectivity (22.4%) to 1,3-PDO at 68.9% glycerol conversion. A series of catalysts derived from silicotungstic acid (SiW) intercalated with CuZnFe hydrotalcite-like compounds (HTLCs) via ion-exchange method was prepared and characterized by N 2 -physisorption, XRD, TEM, SEM, H 2 -TPR, FT-IR, and Py-IR spectra. The intercalation of SiW species into CuZnFe HTLCs was confirmed by these characterization techniques, while the catalytic performance was evaluated for glycerol hydrogenolysis. It was found that introduction of SiW significantly enhanced the selectivity towards 1,3-propanediols (1,3-PDO), owing to the increased Brønsted acid introduction, as demonstrated by Py-IR analysis. The catalyst intercalating 30 wt.% SiW showed the highest selectivity (22.4%) to 1,3-PDO at 68.9% glycerol transformation. The catalytic performance was discussed and correlated with the physicochemical properties of these catalysts. The present contribution provides an economical approach to convert surplus glycerol from biodiesel manufacture to valuable propanediols. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO 2 reduction has been perceived as sustainable to realize the closed-loop carbon cycle and obtain high-energy-dense fuels and chemicals. Nevertheless, the efficient CO 2 reduction into specific hydrocarbons is still highly challenging. In particular, the effects of Cu(0)/Cu(I)/Cu(II) active sites in copper-based catalysts remain elusive. Hence, this work investigated the modulable valence states of Cu(0)/Cu(I)/Cu(II) active sites derived from MOF Cu(btc) under different calcination conditions to enhance CO 2 RR performance. As evidenced by characterizations, the Cu/C-T-air was more inclined to produce C 2 H 4 , which may be associated with Cu(I)/Cu(II) coexistence and abundant oxygen vacancy. Cu/C-450-air showed excellent CO 2 RR properties with 34.8% Faradaic efficiency of C 2 H 4 at 1.1 V vs. RHE after a continuous measurement of 12 h. Meanwhile, the Cu/C-T-H 2 was inclined to produce C 2 H 4 , while Cu/C-T-N 2 tended to produce CH 4 , which may be associated with smaller grain size and thinner carbon layer than the latter to exposure to more active sites and rapid electron transport. Moreover, the mechanism of electrocatalytic CO 2 reduction of Cu/C-T-gas was conjectured. We furnished rational thinking to design Cu/C catalysts with tunable active sites to bolster CO 2 RR. • A strategy was provided to rationally design Cu/C catalysts with modulatable valence states to boost CO 2 RR. • The controllable construction of Cu(0)/Cu(I)/Cu(II) sites were obtained at different calcination condition. • The Cu/C-T-air in CO 2 RR activity was excellent owing to the coexistence of Cu(I)/Cu(II) and oxygen vacancy. • The Cu/C-T-H 2 was inclined to produce C 2 H 4 , while Cu/C-T-N 2 tended to produce CH 4. • The mechanism of electrocatalytic CO 2 reduction of Cu/C-T-gas was conjectured. [ABSTRACT FROM AUTHOR]

Abstract In the presented work, a series of Cr/β zeolites were prepared and used as bifunctional catalysts with Brønsted and Lewis acidity in the conversion of biomass-derived carbohydrates to 5‑hydroxymethylfurfural (HMF). The physicochemical properties of all catalysts were characterized by ICP-AES, N 2 physisorption, solid-state 27Al NMR, XRD, SEM-EDX, UV–Vis, XPS, Raman, NH 3 -TPD and Py-FTIR techniques. It was found that the catalysts with appropriate total acidity, ratio of Lewis to Brønsted acid sites and acid density appear to be beneficial for HMF formation. Under mild reaction conditions, a superior 72% HMF yield with 83% selectivity was achieved from glucose in the H 2 O/THF biphasic system by using the 0.4-Cr/β zeolite catalyst. Moreover, the results of the stability evaluation showed that the catalytic activity of the 0.4-Cr/β zeolite was not significantly lost after four consecutive cycles, and the framework remained intact. Therefore, the catalytic approach proposed in this study is believed to provide potential prospects for the production of HMF from biomass material refining in the future. Highlights • Cr/β catalyst exhibits outstanding performance for the HMF production from carbohydrates. • The acidity of Cr/β catalyst can be tuned by adjusting the loading of chromium. • Cr/β catalyst has good hydrothermal stability and recyclability. [ABSTRACT FROM AUTHOR]

Graphical abstract Synthesis of cyclic carbonates from CO 2 and epoxides. Highlights • Mn-based MOF including imidazole linker was observed with the highest catalytic activity. • Carbon dioxide can be inserted into various epoxides in the presence of Im-MnF sample. • 94.99% yield of allyl-glycidyl carbonate was obtained under the optimal conditions. • A proposed mechanism was in line with the DFT calculation. Abstract The present work is aimed to investigate the catalytic activities of various Mn-based MOFs for carbon dioxide coupling with epoxides. The metal organic frameworks, [(CH 3 NH 3 ][Mn(COOH) 3 ] (MA-MnF), [(CH 3 CH 2 NH 3 ][Mn(COOH) 3 ] (EA-MnF), and [C 3 H 5 N 2 ][Mn(COOH) 3 ] (Im-MnF) were studied via several characterizations such as XRD, FT-IR, XPS, N 2 -adsorption, TG-DSC, CO 2 -adsorption and NH 3 -TPD. Interestingly, Im-MnF compound was observed to possess the highest catalytic activity among the studied compounds, which is associated not only with the amounts of basic sites, but also related to the nitrogen-containing species. 97.27% conversion of allyl-glycidyl ether (AGE, TOF: 36.78 h−1) and 97.66% selectivity to allyl-glycidyl carbonate (AGC) were obtained under the explored optimized conditions (100 °C, 15 bar, 6 h, 1.0 wt% of AGE). In addition, only a slight downward in catalytic activity was found when the sample was reused twice. Furthermore, coupling reactions of CO 2 with various epoxides were also performed, of which, the yield of the cyclic carbonates followed the order: Epichlorohydrin > Allyl glycidyl ether > Styrene oxide > Cyclohexene oxide > Propylene oxide. Finally, a mechanism was proposed, which is in good agreement with the DFT calculation. [ABSTRACT FROM AUTHOR]

Abstract Achieving high yields of 5-hydroxymethylfurfural (HMF) from carbohydrates remains a challenge today. With the aim of developing an efficient and inexpensive catalyst for the production of HMF, manganese phosphate (MnPO 4) was used as the sole catalyst for the catalytic conversion of biomass-derived carbohydrates into HMF in the H 2 O/tetrahydrofuran (THF) biphasic reaction system. The effects of various factors, including reaction temperature, reaction time, system, and catalyst dosage on the conversion of carbohydrates to HMF were explored. An impressing HMF yield of 59% was achieved with glucose as a feedstock at 160 °C for 90 min. Meanwhile, up to 44% of HMF was also obtained with microcrystalline cellulose as a feedstock at 170 °C for 120 min. In addition, MnPO 4 catalyst also displayed outstanding catalytic activities for the conversion of other biomass-derived carbohydrates including monosaccharides and disaccharides. Combined with the dissolution characteristics of the MnPO 4 , a possible catalytic mechanism for the conversion of carbohydrates into HMF catalyzed by MnPO 4 was proposed. The catalytic approach proposed in this paper exhibited a promising potential for HMF production via optimizing the catalytic process. Highlights • MnPO 4 catalyst exhibits a desired catalytic activity for the formation of HMF from carbohydrates. • MnPO 4 can be used as a temperature-controlled phase transfer catalyst in the formation of HMF. • The high activity of the MnPO 4 catalyst is derived from its bifunctional properties exhibited at high temperatures. [ABSTRACT FROM AUTHOR]

Graphical abstract Catalytic conversion of CO 2 over dual-linker MOFs. Highlights • Two dual-linker MOFs were prepared. • Both MOFs showed high catalytic performance for the catalytic conversion of CO 2. • The high activity of MOFs was attributed to the co-existence of acidic and basic sites on MOFs. • A CPC yield of 80.12% was obtained over the catalyst even after five cycles. Abstract In the present work, two dual-linker metal-organic frameworks (MOFs) were prepared with metal salts, terephthalic acid and 4, 4′-bipyridine as precursors, and subsequently used for preparing cyclic carbonates from carbon dioxide and epoxides. These two MOFs were characterized by a number of techniques. The two MOFs prepared showed superior catalytic performance under solventless and co-catalyst-free conditions. In this sense, Co(tp)(bpy) achieved epichlorohydrin (ECH) conversions as high as 95.75% and chloropropylene carbonate (CPC) yields of 94.18% under optimal reaction conditions. The high activity of Co(tp)(bpy) was attributed to the co-existence of Lewis acidic and basic active sites on the catalyst derived from incompletely coordinated metal cations and uncoordinated pyridine groups, respectively. In addition, Co(tp)(bpy) maintained this high catalytic performance after five consecutive reaction cycles. A possible reaction mechanism was proposed based on the experimental results. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Ag@Co-PIN-NH 2 catalyst was prepared via green ion exchange loading method. • Ag@Co-PIN-NH 2 exhibited high dispersed active phase and CO 2 adsorption capacity. • The novel catalysts showed catalytic diversity for flue gas CO 2 conversion at ambient reaction conditions. • Ag@Co-PIN-NH 2 remained highly active for four successive reuses. Most of the strategies developed to convert CO 2 to high value-added chemicals require high purity of CO 2. To reduce the energy consumption of CO 2 purification, this work reports the preparation of a poly(ionic liquid)s catalyst Ag@Co-PIN-NH 2 with dual functions of adsorption and activation. The –NH 2 functional group was introduced into the organic polymer framework and the Ag(I) active phase was deposited on the framework carrier through anionic exchange reaction. The highly polar surface and highly dispersed active phase of Ag@Co-PIN-NH 2 facilitated the carboxylative cyclization and hydration of propargylic alcohols with exclusive chemo-selectivity under low pressure and concentration of CO 2 (1 bar, 15 % CO 2 in 85 % N 2 , v/v simulated flue gas). Furthermore, Ag@Co-PIN-NH 2 exhibited broad substrate scope, excellent catalytic diversity and reusability. This work provides momentous reference information for conversion of carbon resources in industrial flue gas into valuable chemicals. [ABSTRACT FROM AUTHOR]

We present here a study of the production of furfural from xylose and wheat straw using the chromium phosphate (CrPO 4 ) with Lewis and Brønsted acidity as a highly efficient catalyst in the water/tetrahydrofuran (THF) biphasic system. The effects of various reaction parameters including reaction temperature, reaction time, system, and catalyst dosage were explored to evaluate the product yield. Under CrPO 4 catalysis, an excellent furfural yield could reach 88% from the xylose at 160 °C for 60 min. Meanwhile, 67% furfural and 32% 5‑hydroxymethylfurfura (HMF) were simultaneously achieved from wheat straw at 180 °C for 90 min. Mechanistic studies suggested that the perfect catalytic activity of CrPO 4 was due to its inherent bifunctional catalysis activity. It was found that the CrPO 4 was easily to be recovered and a great catalytic activity was available after four cycles, which not only contributed to a sustainably reduced energy consumption on catalyst recovery, but also reduced the concerns associated with toxic chromium element. [ABSTRACT FROM AUTHOR]

A highly shape-selective H[Zn,Al]ZSM-5/SiO 2 composite catalyst was prepared by direct incorporating Zn species via isomorphous substitution into the zeolite framework and subsequent SiO 2 deposition on zeolite surface. Its catalytic performance in methanol to aromatics (MTA) was compared with Zn/HZSM-5/SiO 2 prepared by impregnation of Zn species and subsequent SiO 2 deposition. The textural properties and acidic properties as well as the subsequent catalytic performances of the resultant catalysts in MTA reaction were obviously influenced by the introduction method of Zn species. H[Zn,Al]ZSM-5/SiO 2 prepared by isomorphous substitution contained more inter-crystalline voids, which provided much space to resist deposition of coke and avoided quick blockage of micropore entrances. In contrast, Zn/HZSM-5/SiO 2 prepared by impregnation contained sub-nanometric ZnO clusters at the pore entrances, which might restrict large molecule products diffusion and deteriorated the catalyst deactivation. Moreover, the sum of strong and medium acid sites in H[Zn,Al]ZSM-5/SiO 2 was more than that in Zn/HZSM-5/SiO 2 , which meant there were more active sites for cyclization and aromatization steps in MTA reaction in the former. As a result, the lifetime of H[Zn,Al]ZSM-5/SiO 2 was almost twice that of Zn/HZSM-5/SiO 2 . In addition, the enhancement in catalytic activity by Zn introduction and the improvement in para-selectivity in xylene by SiO 2 deposition were also studied. Finally, nearly 100% methanol conversion, 95.6% para-selectivity in xylene and 18.2% para-xylene yield were simultaneously obtained over the stable H[Zn,Al]ZSM-5/SiO 2 (with 24 h lifetime) in MTA reaction. [ABSTRACT FROM AUTHOR]

Hierarchical H[Sn, Al]ZSM-5 zeolites were successfully prepared by hydrothermal method with directly incorporating Sn species into framework of HZSM-5 zeolites followed by alkali treatment. The prepared samples were characterized by XRD, BET, SEM-EDX, TEM, NH 3 -TPD, FT-IR and Py-IR. The results indicate that Sn species were successfully incorporated into HZSM-5 zeolites. The catalytic performances of all prepared zeolites were evaluated by glycerol aromatization. The highest catalytic performance of GTA synthesis was observed with H[Sn, Al]ZSM-5 treated with 0.3 M NaOH (32.1% carbon yield of BTX aromatics and 13 h catalyst lifetime), which was prior to the pure HZSM-5 (17.8% carbon yield of BTX aromatics and 3 h catalyst lifetime). The remarkably improved performance in catalytic activity and stability of H[Sn, Al]ZSM-5/0.3AT zeolitize could be attributed to synergy effect between Sn species doped into HZSM-5 zeolite and the generated micro-mesoporous structure by alkali treatment. [ABSTRACT FROM AUTHOR]

The conversion of CO 2 into high value-added chemicals through efficient catalysis is an ideal strategy to reduce atmospheric CO 2 pollution and achieve carbon neutrality. Therefore, amino-functionalized organic polymer Cu@Co-PIL-N 4 loaded with highly dispersed CuI as a novel catalyst was developed. The functionalization of the surface and the high dispersion of the active phase integrate CO 2 capture and conversion into one catalytic system. The locally enriched CO 2 is converted to the easily activated carbon-oxygen negative ion by the action of primary or secondary amines. Thus, it is easier to achieve efficient preparation of α-alkylidene cyclic carbonates (STY = 20.8 h−1) by CO 2 carboxylative cyclization under mild conditions (25 °C, CO 2 pressure of 1 bar). The addition of a small amount of water to the cyclization system boosted domino reaction to convert the α-alkylidene cyclic carbonates to α-hydroxy ketones. The domino reaction also exhibited efficient catalytic activity and outstanding regioselectivity. In addition, the Cu@Co-PIL-N 4 catalyst exhibited excellent substrate expansion and cyclic regeneration for both reactions. This work promises great significance for further developing cost-effective and high-performance catalysts for the chemical conversion of CO 2. [Display omitted] • A novel Cu@Co-PIL-N 4 catalyst was prepared via ion-exchange deposition route. • Cu@Co-PIL-N 4 integrates CO 2 adsorption and capture into one catalytic system. • The novel catalysts exhibited high catalytic efficiency and diversity for CO 2 conversion. • Cu@Co-PIL-N 4 remained highly active for four successive reuses. Typically, the CO 2 concentration in flue gas is very low (around 15%), thus capturing CO 2 from flue gas requires high energy consumption and various purification processes [ 49 , 50 ]. Attributed to the excellent ability of Cu@Co-PIL-N 4 catalyst for CO 2 gas capture, it was applied for the carboxylative cyclization under dilute gas and achieved α-alkylidene cyclic carbonate yield of 68%. Therefore, attributed to these intriguing characteristics, this newly developed catalytic system provides a new strategy for CO 2 capture and flue gas utilization in the field of CCUS (Fig. 5). α-hydroxy ketone is a very important and widely used compound [ 52 , 53 ] as biologically active natural product, pharmaceutical intermediate, and a photoinitiator in UV-curable coatings [ 54 ]. Therefore, the synthesis of α-hydroxy ketones via the triple component reaction of PA-CO 2 -H 2 O is a fascinating strategy bearing the advantages of easy availability of raw materials and green sustainability [ 55 ]. This domino synthesis strategy was further developed by adding a small amount of water to the existing carboxylative cyclization catalytic reaction system. Instead of α-alkylidene cyclic carbonate, 87% of the downstream product α-hydroxy ketone was obtained without any other by-products (Fig. 7). The PAs with different substituents as substrates also generated the corresponding hydroxyl ketones. [ABSTRACT FROM AUTHOR]

[Display omitted] • A CoCo PBA/CoSn(OH) 6 /Pt heterojunction with unique inlaid structure is constructed. • Visible-light-driven high selectivity conversion of simulated flue gas is achieved. • Multichannel electron transmission promotes the separation and migration of photocarriers. • A structure-modulated photocatalytic reaction mechanism is proposed. Converting industrial waste gas into high-value chemicals is crucial to sustainable economic development. Herein, through a coordination strategy of facet-selective etching and in-situ growth, the CoCo Prussian blue analogue (PBA)/CoSn(OH) 6 /Pt heterojunction was designed and prepared with multiple interfaces and dual interconnection networks, which is suitable for photocatalytic conversion of simulated flue gas. This unique structure is conducive to multi-channel electron transmission and multiple light scattering, promoting the separation and migration of photogenerated carriers. This photocatalyst can synergistically regulate charge potential and kinetics, and enhance CO 2 activation. Therefore, the CO generation rate (11.7 µmol·g−1·h−1) and selectivity (91.8 %) of the CoCo PBA/CoSn(OH) 6 /Pt heterojunction were significantly improved without using additional photosensitizer or sacrificial agent. The mechanism and reaction pathway of photocatalytic CO 2 reduction were further studied by in-situ technology and density functional theory (DFT) calculation. This study offers knowledge about the preparation of high-efficiency photocatalysts for flue gas conversion and structure-modulated photocatalytic reaction. [ABSTRACT FROM AUTHOR]

CuNi bimetallic nanoparticles embedded in carbon matrix (CuNi@C) were synthesized and applied in the selective conversion of biomass-derived furfural to cyclopentanone. The catalysts were prepared directly from thermolysis of Cu-based metal–organic frameworks (MOFs) impregnated with nickel nitrate. Compared with traditional precipitation method, relatively high surface area (91.6 m 2 /g) and nano-sized (about 15 nm) metallic copper and nickel particles can be obtained when molar ratio of nickel to copper was 0.5. Furthermore, the porous carbon matrix can not only act as a supporter but prevent the accumulation of metal particles. By varying the molar ratio of nickel to copper, CuNi 0.5 @C shows best catalytic performance (99.3% conversion of furfural and 96.9% yield of cyclopentanone) at optimum conditions (130 °C, 5 h, 5 MPa) attributed to the above mentioned properties. In addition, the CuNi 0.5 @C can be reused four times with good activity and stability. Hence, current work presents a new and facile method to prepare CuNi bimetallic catalysts which has a brilliant performance in catalytic conversion of furfural to cyclopentanone. [ABSTRACT FROM AUTHOR]

SO 3 H-Functionalized ionic liquids containing halogen-anions were successfully synthesized and used as catalyst for conversion of biomass to levulinic acid, a high levulinic acid yield of 76.5% was achieved when used cellulose as substrates. [Display omitted] • Synthesis and characterization of SO 3 H-functionalized ionic liquids containing halogen-anions. • The yield of LA is up to 76.5% at reaction time of 20 min with using [BSim]Br as catalyst. • The [BSim]Br was easily recycled and showed high catalytic activity even after four cycles. • The yield of LA were dependent on the anions and in the order of increase: F- ＜ Cl- ＜ Br-. The conversion of cellulose to levulinic acid (LA) and other platform chemicals is a promising route to solve the energy crisis. For this purpose, a series of new SO 3 H-functionalized ionic liquids (ILs), containing different halogen-anions were synthesized and applied for catalytic conversion of cellulose to LA. The structure, thermal stability, and acidity of SO 3 H-functionalized ILs were characterized by Nuclear magnetic resonance (NMR) spectra, Fourier-transform infrared (FT-IR), High resolution mass spectrometry (HRMS), thermogravimetric analysis (TGA), and Hammet acidity method. The results revealed that as the size of halogen anions increased, the Hammett acidity gradually increased from SO 3 H-functionalized ILs containing fluorine- to chlorine- and then to bromine-anions. When SO 3 H-functionalized ILs were used as a catalyst for the production of LA from cellulose, the yield of LA gradually increased as the size of halogen-anions increased from fluorine- to chlorine- and then to bromine-anions. Among the SO 3 H-functionalized ILs, 1,1-bis(3-(4-sulfobutyl)imidazolium-1-yl)butylene bromine ([BSim]Br) exhibited the best catalytic activity with 76.5% yield of LA in cellulose/[BSim]Br/H 2 O (m / m / m = 1:9:8) reaction system at 180 °C for 20 min, which was the highest yield compared to previous literature reports using ILs as catalyst. Besides, the [BSim]Br was easily recovered and showed high catalytic activity after five cycles. The efficient catalyst, [BSim]Br is then proposed to have a great potential for mass production of LA from biomass. [ABSTRACT FROM AUTHOR]

• Synthesis and characterization of SO 3 H-functionalized ionic liquids. • Efficient conversion of cellulose to levulinic acid using SO 3 H-functionalized ionic liquids. • The yield of LA is up to 65% at the optimum condition with using [BSim]HSO 4 as catalyst. • The [BSim]HSO 4 was easily recycled and showed high catalytic activity even after four cycles. A series of new SO 3 H-functionalized ionic liquids (ILs) were synthesized and characterized, which were successfully applied to catalyze cellulose to produce levulinic acid (LA) via one-pot reaction. The structure, thermal property, and acidity of ILs were characterized by NMR, TGA, and Hammett acidity measurement. The Hammett acidity (H 0) of ILs increase in the following order: [BSim]H 2 PO 4 <[BSim]TsO < [BSim]CF 3 SO 3 < [BSim]HSO 4 , which is consistent with their yield of LA order using these ILs as catalysts. Under the optimum conditions, the yield reached up to 65% when [BSim]HSO 4 was used as catalyst and solvent, which is one of the best results compared to those reported in literature. Moreover, the ILs were easily recycled without structural change even after four cycles, and the yield of LA was up to 44% at the fifth cycle. Furthermore, TGA indicated that these SO 3 H-functionalized ILs exhibited excellent thermal stability. These efficient ILs will provide new options for converting biomass resources to LA and other chemicals. [Display omitted] [ABSTRACT FROM AUTHOR]