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China accounts for more than 50% of the global total cement production, the emission of pollutants in the cement industry occupies a large proportion of the industries. Some provinces have first carried out in-depth treatment of the cement industry, and the national level will also introduce an implementation plan for ultra-low emission transformation of the cement industry to promote continuous improvement of China's air quality. In this work, a pollutant emission inventory covering the full life cycle of the cement industry, including organized emission, unorganized emission and transportation, was established based on pollutant discharge permit, Continuous Emission Monitoring System (CEMS) database and field investigation. And, the emission reduction potential of particulate matter (PM), sulfur dioxide (SO 2) and nitrogen oxide (NOx) after the implementation of ultra-low emission transformation in cement industry was evaluated. The results show that the existing dedusting, desulphurization and denitration technologies can control the concentrations of PM, SO 2 and NOx below 10 mg/m3, 35 mg/m3 and 50 mg/m3, respectively. The emission reduction potential of PM, SO 2 and NOx in cement industry is 259.54 kt, 14.98 kt and 607.04 kt, corresponding emission reduction ratio is 37%, 24% and 64%, respectively. In addition, this work reveals the spatial characteristics of pollutant emission level and emission reduction potential of the cement industry, which is conducive to the rational layout of ultra-low emission transformation, and push forward the transformation task by area and stage. [Display omitted] • The full life cycle emission inventory of China's cement industry was established. • Cleared the accessibility of treatment technology through CEMS data and field research. • The transport distance of raw materials and products was clarified by transport matrix. • The spatial characteristics of pollutant emission levels in cement industry were revealed. • The full life cycle emission reduction potential of pollutants after ULET was calculated. [ABSTRACT FROM AUTHOR]

The heat desorption of styrene from adsorbents is impracticable owing to its spontaneous polymerization under heating conditions. However, the feature also brings a potential promoting effect on styrene adsorption. Therefore, it is expected to develop the non-regenerative adsorbents with large adsorption capacity by strengthening the polymerization effect. In this work, C–Cl grafted silica gel adsorbents were prepared by introducing (Chloromethyl)dimethylchlorosilane (CMDMCS) and FeCl 2 into silica gel. The C–Cl grafted silica gel exhibited excellent styrene adsorption performance, its adsorption amounts for styrene were 4.67 times and 9 times of unmodified silica gel under dry air condition and high humidity condition (RH = 80%), respectively. In addition, the adsorption of styrene on C–Cl grafted silica gel was almost unaffected by the presence of toluene. The characterization of adsorbents after styrene adsorption indicated that the improvement of adsorption capacity of C–Cl grafted silica gel for styrene can be attributed to atom transfer radical polymerization (ATRP) of styrene molecules on modified silica gel during adsorption process. [Display omitted] • C–Cl grafted SiO 2 adsorbents were prepared by introducing CMDMCS and FeCl 2. • The adsorption capacity of SiO 2 -1.5 for styrene was 4.7 times of SiO 2. • The adsorption of styrene on C–Cl grafted SiO 2 was almost unaffected by toluene. • C–Cl grafted SiO 2 showed excellent moisture resistance for styrene adsorption. • ATRP occurred during the adsorption process of styrene on C–Cl grafted SiO 2. [ABSTRACT FROM AUTHOR]

SnO 2 -based materials have been widely studied because of their high theoretical specific capacity, whereas the significant capacity fading is caused by the low reversibility conversion reaction and volume expansion. In this work, we proposed a precipitation-polymerization-thermal treatment method to construct SnO 2 -based composites by precipitation reaction of SnCl 2 with moderately exfoliated graphite (MEG), subsequent dopamine (DA) polymerization and thermal treatment to fulfill nitrogen-doped-carbon (NC) coating and part transformation of SnO 2 to Sn. Finally, we can obtain the SnO 2 /Sn/MEG@NC composites for high-performance lithium-ion batteries (LIBs). The conductive NC coating and MEG matrix have the function in facilitating electron transportation, restraining aggregation, and adapting to volume change of SnO 2 /Sn particles. Micron-sized Sn is broken during the cycles and forms nano-sized distribution with ultrafine SnO 2 , the hybrid SnO 2 /Sn allows highly effective reversibility conversion and alloying/de-alloying reactions upon cycles. As a result, the SnO 2 /Sn/MEG@NC electrode exhibits outstanding cycling stability (837.2 mAh g−1 at 1 A g−1 after 800 cycles), displaying outstanding performance for being LIBs. [ABSTRACT FROM AUTHOR]

Fine particular matter (PM 2.5) pollution still occurs frequently in China. Despite recognizing the importance of regional joint prevention and control (RJPC) for mitigating haze pollution, there is still a limited understanding of scheme design and effectiveness. In this study, with the Fenhe Plain in China serving as the case, the Integrated Source Apportionment Method (ISAM), incorporated into the Community Multiscale Air Quality Modeling System (CMAQ), was used to quantitively identify PM 2.5 sources during a typical heavy pollution episode from Jan. 20th to 25th, 2021. Informed by source apportionment, we designed and assessed multiple RJPC scenarios for eliminating heavy pollution, yielding recommended RJPC schemes. Source apportionment results revealed a substantial increase in the contribution percentage of regions within a 350-km radius during the pollution episode compared to the non-polluted period. Sulfate was predominantly contributed from long-distance transport, whereas nitrate was chiefly contributed from closer regions. Ammonium exhibited higher local contributions than nitrate from the Fenhe Plain. Moreover, Taiyuan and Linfen were identified as PM 2.5 exporters, whereas Sanmenxia, Jinzhong, and Luliang served as PM 2.5 importers, and Yuncheng acted as a comprehensive city. The proposed specific RJPC schemes aimed at eliminating heavy pollution for the Fenhe Plain emphasized the importance of controlling emissions of particulate matter, ammonia, nitrogen oxides, and volatile organic compounds in areas within an approximate 350-km radius outside the Fenhe Plain, in addition to strengthening the local emission control. Nevertheless, only through the comprehensive and in-depth implementation of emission control measures across a larger area can PM 2.5 compliance be achieved. [Display omitted] • A framework for developing regional joint prevention and control (RJPC) schemes was presented. • Typical cities of PM 2.5 export and import in the Fenhe Plain were identified. • Areas within an approximate 350-km radius notably contributed to PM 2.5 and its components. • Specific RJPC schemes were proposed to eliminate heavy haze pollution episodes. [ABSTRACT FROM AUTHOR]

Promoting the ultra-low pollutant emission retrofit of the cement industry, as the third largest industry in terms of air pollutants and carbon dioxide (CO 2) emissions in China, has become an important part of achieving carbon peaking and carbon neutrality. In this work, the current status of pollutant emission in cement industry and the pollutant emission limit value of ultra-low emission retrofit in typical provinces were analyzed. And, the collaborative air pollutants and CO 2 emission reduction potential and cost-benefit were assessed in six types of ultra-low pollution emission retrofit scenarios. The results indicate that the emission reduction of particulate matter (PM)，sulfur dioxide (SO 2) and nitrogen oxides (NOx) in six scenarios are 10%–15%, 1%–5% and 26%–64%, respectively. The construction investment of 43.8 billion Yuan is needed to complete the retrofit of production lines when the pollutant emission limit value is set as 10 mg/m3, 35 mg/m3 and 50 mg/m3 for PM, SO 2 and NOx, which is 6 times of that when the pollutant emission limit value is set as 10 mg/m3, 50 mg/m3 and 100 mg/m3. However, the cost per unit equivalent of pollutant abatement of the former is only 36% of the latter. The emission reduction potential of CO 2 in six scenarios is 0.4%–0.6%, indicating that the ultra-low pollutant emission retrofit in cement kiln has limited effect on CO 2 emission reduction potential. Comprehensive analysis of emission reduction potential and cost-benefit, it is more economical and reasonable for China cement kilns to choose the path of ultra-low emission retrofit in scenario 4. • The production capacity and pollution status of cement kiln were analyzed. • Six ultra-low pollutant emission retrofit scenarios were designed. • Identified the best path of ultra-low emission retrofit in cement industry. • The ultra-low pollutant emission retrofit can reduce pollutants and CO 2 emission. • The retrofit of pollutants and CO 2 emission should be carried out simultaneously. [ABSTRACT FROM AUTHOR]

Mixing transition-metal phosphates Li 3 V 2− x Fe x (PO 4 ) 3 (0≤ x ≤2) were first designed to be a type of intercalated and deintercalated cathodes to obtain high specific capacity for safe Li-ion batteries. Since the residual oxygen in the quartz tube furnace and pellet would oxidize the V 3+ to V 4+ in the Ar ambience during the sintering process, trace amounts of acetylene black inside and outside the pellet could play a role of deoxidizer to protect V 3+ meanwhile ensure Fe 3+ not reducing to Fe 2+ . With the concerted effort of inside and outside acetylene black, monoclinic structure Li 3 V 2− x Fe x (PO 4 ) 3 (0≤ x ≤2) solid solutions had been successfully fabricated via a two-step synthesis method. X-ray diffractions with Rietveld refinement revealed that V1-sites were the preferred position when Fe 3+ ions doped into Li 3 V 2 (PO 4 ) 3 , which means, every V1-site was occupied with the same probability by V 3+ and Fe 3+ when 0< x <1, and then for V2-site when 1< x <2. X-ray photoelectron spectroscopy result showed the presence of trace amounts of acetylene black had realized the coexist of V 3+ and Fe 3+ in the Li 3 M 2 (PO 4 ) 3 framework. When evaluated as cathodes for Li-ion batteries, the pure Li 3 V 2 (PO 4 ) 3 electrode displayed the highest charge (137.2 mAh g −1 ) and discharge (121.5 mAh g −1 ) capacities in the first cycle, with the increase of Fe 3+ content, all the charge and discharge capacities reduced drastically. Furthermore, the EIS results showed that the incorporation of the sluggish Fe 3+ ions reduced the electronic conductivity and lithium conductivity, which in turn contributed to the poor electrochemical performance. Although our results did not show Fe 3+ /Fe 2+ electrochemical activity contrary to our expectation, this preliminary study on Li 3 V 2− x Fe x (PO 4 ) 3 (0≤ x ≤2) have provided a prerequisite for further improving the electrochemical properties by nanosizing and carbon-coating to better use these mixing transition-metal phosphate cathodes in the future. [ABSTRACT FROM AUTHOR]