FUEL
·
2021
·
IF 6.609
Hua Tang,Hongyun Hu,Aijun Li,Baojun Yi,Xian Li,Dingding Yao,Hong Yao,Haoran Yuan
Thermo-chemical recycling of waste tire to generate pyrolytic char as alternative carbon black is a promising route for waste disposal and environmental sustainability. However, impurities in waste tire (like Zn, Si, Ca and S) are probably enriched in the pyrolytic char, and removal of those impurities is of great importance for char recycling. To avoid generating large amount of waste acids and polluted gases in the traditional impurities removing process, molten salt (Na 2 CO 3 -NaOH) thermal treatment was creatively proposed in the current work. The influence of operational temperatures (in the range of 350 to 450 °C) was investigated in relation to the efficiency of impurity removal. Results show that the removal efficiency of impurity components was firstly increased but then weakened by increasing treating temperature from 350 to 450 °C, while the highest removal rate was obtained at 400 °C. Generally, the current system could effectively remove more than 80% of ash and 70% of sulfur at 400 °C, with the recovery rate of char between 71% and 83%. Specifically, calcium carbonate/sulfate was removed from the char due to its good solubility in the molten salts. In addition, molten salts showed good activity to convert char contained inorganic sulfides and ·SH radicals into salts-soluble Na 2 S. Similarly, silicon and zinc were tended to be transformed into soluble silicate and zincate, which had higher solubility in the used molten salt. In addition, the agglomerated char particles were separated into smaller and more uniform size during molten salt thermal treatment.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Science China-Technological Sciences
·
2022
·Vol. 65
·期 10
·2337-2347
·
IF 3.903
Hou ShengPing,Zhang Da,Xie ZhiPeng,Kang Yao,Tang ZhengGang,Dai YongNian,Lei Yong,Chen Jian,Liang Feng
As the quantity of waste tires increases, more pyrolysis carbon black (CBp), a type of low value-added carbon black, is being produced. However, the application of CBp has been limited. Therefore, it is necessary to identify and expand applications of CBp. This work focuses on the preparation of activated carbon (AC) from CBp using the physicochemical activation of carbon dioxide (CO 2 ) and potassium hydroxide (KOH). Thereafter, AC is applied to the electrode of the electrical double-layer capacitor (EDLC). The AC prepared by CO 2 /KOH activation exhibited a hierarchical pore structure. The specific surface area increased from 415 to 733 m 2 g −1 , and in combination with low ash content of 1.51%, ensured abundant ion diffusion channels and active sites to store charge. The EDLC comprising the AC (AC-2) electrode prepared by excitation of CO 2 (300 sccm) and KOH had a reasonable gravimetric specific capacitance of 192 F g −1 at 0.5 A g −1 , and exhibited a good rate capability of 73% at 50 A g −1 in a three-electrode system. Moreover, the EDLC device comprising the AC-2 electrode delivered excellent cycling stability (capacitance retention of 106% after 10000 cycles at 2 A g −1 in a two-electrode system). Furthermore, a symmetric supercapacitor based on an AC electrode that exhibits a supreme energy density of 4.7 Wh kg −1 and a maximum power density of 6362.6 W kg −1 is demonstrated.
研究领域:
材料科学
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环境科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
WASTE MANAGEMENT
·
2022
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IF 8.816
Chan Zou,Yang Ren,Songgeng Li,Hongyun Hu,Chengyang Cao,Hua Tang,Xian Li,Hong Yao
Pyrolysis is a technical means for waste tires recycling, which can promote the enrichment of carbon black and facilitate the subsequent recovery. However, carbon black particles aggregated and the inorganic impurities tended to be enriched in pyrolytic char during the waste tire pyrolysis process, which is not conducive to the substitution of commercial carbon black by pyrolytic char. In the present study, a novel method using molten salts thermal treatment was proposed for the impurities removal from pyrolytic chars with different characteristics. In addition, the proper thermal treatment conditions were further estimated to obtain better performance for the physical–chemical properties improvement of pyrolytic char. Six kinds of char samples were chosen to conduct molten salts thermal treatment (MSTT) experiments at 350, 400, and 450 °C. The experimental results show that MSTT can effectively remove the impurities of different pyrolytic chars, and the most optimum reaction conditions are at 400 °C, 2 h of reaction time, and molten salt/char ratio of 10:1. In addition, after MSTT, the pyrolytic char was depolymerized, and the average particle size reduced from 36.63 μm to 19.08 μm, the specific surface area increased from 49 m 2 /g to 73 m 2 /g. At the same time, the graphite carbon content of the pyrolytic char increased from 24.41% to 70.90%, and the hydroxyl content on the pyrolytic char surface increased significantly. In summary, the physical–chemical properties of waste tire pyrolytic char were improved by MSTT, which is close to the carbon black N550 level.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Gan Wan,Tao Chen,Linlin Xu,Lushi Sun,Ben Wang,Wu Yang,Li Lin
Brominated flame retardants (BFRs) in waste printed circuit boards (WPCBs) can lead to severe environmental pollution. However, brominated materials have been demonstrated to play a substantial role in elemental mercury (Hg 0 ) removal. In our preceding research, WPCB-derived chars were successfully prepared for the removal of Hg 0 from flue gas with decent performance. On this foundation, this work employed a non-thermal plasma (NTP) reactor to modify WPCB-derived chars with the objective of further improving Hg 0 removal efficiency. Various characterizations and adsorption tests were conducted to investigate the effects of modification power, time, and atmosphere on Hg 0 removal efficiency. Under the optimal condition, the Hg 0 removal efficiency of NTP-modified chars was increased by 20%. However, an extended modification period and the high power resulted in the deterioration of active functional groups and carbon erosion, leading to a notable reduction in Hg 0 adsorption efficiency. The NTP modification incorporated oxygen atoms onto the surface of modified char to form C(O)-O-C functional groups. Additionally, NTP modification promoted the formation of active CuO sites in copper-containing pyrolytic chars. The adsorption kinetics and mechanisms indicated that NTP modification primarily promoted chemisorption. The CuO and C(O)-O-C functional groups were the main oxidation active sites that significantly improved the Hg 0 removal performance.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 142
·期 3
·e56377
·
IF 2.7
Yaqi Ge,Pengfei Diao,Xiangxu Li,Yukun Zhou,Zhenchun Xu,Huiguang Bian,Yao Xiao,Chuansheng Wang
In this paper, pyrolysis carbon black (CBp) was introduced into nitrile butadiene rubber (NBR), the effects of the ratio of CBp and carbon black (N326) on the properties of NBR composites were investigated, and the optimal ratio was determined. On this basis, the accelerator DPG, coupling agent KH550 and CBp were modified by ball milling and plasma. The results showed that when the ratio of CBp to N326 was 40:15, the overall properties of NBR composites was better. Compared with the unmodified CBp/NBR composites, the change rate of tensile product, resilience and DIN abrasion of ball milling-plasma modified CBp/NBR composites in oil environment were reduced by 52.96%, 12.81%, and 27.19%, respectively, and the tear strength after double damage by high temperature and oil bath was increased by 15.63%, which resulted in better oil and high temperature-resistance. In summary, the ball milling-plasma combined with DPG/KH550 modified CBp can not only replace N326 carbon black, but also realize the preparation of NBR composites with better oil and high temperature-resistance.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2020
·
IF 5.715
Jie Li,Lanjia Pan,Guangwei Yu,Chunxing Li,Shengyu Xie,Yin Wang
Utilization of sludge pyrochar (SP) is the terminal step to loop the entire harmless disposal process of sewage sludge with pyrolysis . A new, easily recyclable, and safe adsorbent with well-immobilized heavy metals (HMs) was prepared from SP for ciprofloxacin (CIP) adsorption. The operational conditions for the adsorbent preparation were systematically optimized based on recycling rate and adsorption performance. Additionally, the adsorption conditions, adsorption kinetics, isotherms, and regeneration of adsorbents were further investigated in the present study. The results showed that easily recyclable and safe adsorbents were successfully prepared at 1100 °C under N 2 atmospheric conditions (SPA-N-1100) with a maximum CIP adsorption capacity of 10.42 mg/g. SPA-N-1100 exhibited good CIP adsorption performance at an adsorption temperature of 45 °C and pH between 8.0 and 9.0. The adsorbents were regenerated by thermal desorption at 450 °C with a thorough decomposition of CIP. The adsorption mechanism was mainly dominated by its special porous microspheres-accumulation structure and surface species (e.g., FeP and graphite). Moreover, HMs in the adsorbents were well immobilized in SPA-N-1100 by the generation of new metal mineral phases and encapsulation of melting minerals, which had an ultralow potential for ecological risk during application.
研究领域:
环境科学
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化学工程
·
水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2023
·
IF 8.9
Lu Liu,Jian Wang,Huijuan Yang,Di Gao,Yaya Cui,Hao Chen,Yaxin Qin,Ranfeng Ye,Xing Ding
The widespread use of polychlorophenols poses enormous environmental challenges. Biochar has the potential to accelerate the transformation of polychlorophenols. But the biochar-triggered photochemical decomposition mechanism of polychlorophenols still remains unclear. Herein, the photochemical behavior of pyrochar was comprehensively investigated in 2,4,6-trichlorophenol (TCP) remediation. Researches revealed that persistent free radicals (PFRs) and oxygenated functional groups (OFGs) on the surface of pyrochar cooperatively promoted ROS generation for TCP degradation. PFRs performed a key role of electron-donating and energy transfer in ROS conversion, especially in the activation of H 2 O 2 into •OH. The hydroxyl groups of photosensitive components of pyrochar were photo-excited and provided electrons for enhanced ROS formation as well. With photogenerated ROS involved, more TCP was decomposed through dechlorination under light irradiation than that in the dark, in which 1 O 2 , •OH, and •O 2 − were the dominant active species. During this process, stronger light intensities (3 W/m 2 ) and shorter light wavelengths (400 nm) can provide more energy for the activation of PFRs and OFGs, promoting the decomposition of TCP. This work casts a new light on the environmental roles of pyrochar in the photochemical removal of polychlorophenol pollutants.
研究领域:
环境科学
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化学工程
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2023
·
IF 6
Shi-yu Feng,Kai Li,Ting Huang,Cheng-bo Zhang,An-qing Zheng,Yan-qin Huang,Shi-guan Yang,Qiang Lu
This study presented a novel method for the simultaneous generation of monophenol chemicals and carbon-based CO 2 adsorbent from polycarbonate (PC) by using salt solution-enhanced pyrolysis. The regulatory functions of several factors on the production of 4-isopropenylphenol (IPP) and phenol were investigated using a laboratory-scale pyrolysis reactor , including salt solution type (neutral, acidic, and alkaline), solution concentration, and pyrolysis temperature. The results revealed that the Na 2 CO 3 solution exhibited the best ability to enhance the preparation of IPP and phenol. At Na 2 CO 3 concentration of 1 mol/L and pyrolysis temperature of 600 °C, the optimum yields of IPP and phenol reached 28.83 wt% and 33.77 wt%, respectively. The pyrolysis char (PCSC) obtained under this condition exhibited good CO 2 adsorption behavior with a maximum adsorption capacity of 1.75 mmol/g at 30 °C because of its well-formed porous structure and copious oxygen-containing functional groups.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）