ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
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2024
·Vol. 46
·期 12
·1-17
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IF 3.2
Liu Anrong,Feng Li-Juan,Ou Yangyang,Zhang Xiaoya,Zhang Jinhong,Chen Hongyan
Biochar has been widely used to solve the wastewater pollution of polycyclic aromatic hydrocarbons (PAHs). However, the competition of PAHs with different benzene ring numbers (e.g., phenanthrene [Phe], pyrene [Pyr], and benzo[a]pyrene [BaP]) for adsorption sites on biochar has received little attention. In this study, biochar was produced by co-pyrolysis of sludge and phosphorus tailing at different temperatures (300, 500, or 800 °C) to adsorb PAHs. The results show that phosphorus tailing increased the adsorption of PAH by increasing the biochar’s BET surface area (S BET ), micropore volume, hydrophobicity (at low temperatures) and aromaticity (at high temperatures). The maximum adsorption capacities were 29.90 µmol/g for Phe, 25.58 µmol/g for Pyr and 20.45 µmol/g for BaP, respectively. Importantly, the types and functions of groups involved in the adsorption of various PAHs were discussed. Adsorption of Phe and Pyr on the biochar mainly involved C=O and C–O–C functional groups, and there was a certain degree of competition between these PAHs for those sites. In contrast, BaP mainly adsorbed at C–OH and C=C moieties, without competing with Phe or Pyr at C–OH sites. The competitive edge of BaP was also stronger than that of Phe and Pyr on C=C functional groups. The adsorption mechanisms involving pore filling, hydrophobic interactions, and π – π interactions governed the adsorption of the evaluated PAHs. Overall, the adsorption of PAHs on biochar followed a heterogeneous chemical adsorption process.
研究领域:
环境科学
·
化学
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产品关联
DOI
PubMed
高影响因子
Biomass Conversion and Biorefinery
·
2024
·
IF 3.5
Yao Pin,Yan Tinggui,Dai Xin,Xiao Ya,Xiang Weixue,Wu Yunqi
Deposition and corrosion in boilers caused by the release of alkali compounds in agricultural residua pose significant challenges to the widespread utilization of biomass energy. Phosphate tailings (PT), which is rich in Ca, Mg, and P, have the potential to mitigate the potassium (K) release of biomass straw. However, the impact of PT on K immigration has not been investigated. To elucidate the influence of PT on K immigration, thermal analysis, K concentration determination, and mineral evolution during heating of ash were conducted. These results were compared with those obtained from biomass mixed with kaolin, an effective additive known to alleviate K release in biomass. The findings revealed that PT resulted in lower K release at temperatures below 600 ℃ compared to kaolin. Because the reaction between PT and K-compounds to form K-phosphate occurs more readily than the formation of K-silicate at lower temperatures. However, the effectiveness of PT diminished as the temperature increased. One reason is the decomposition of K-phosphate, resulting in the volatilization of K at higher temperatures. Another reason is the competition among Ca, Mg, and K for the opportunity to react with Si and Al, leading to the formation of more stable Ca and Mg aluminosilicate and facilitating the release of K. It is noteworthy that the addition of kaolin to rice straw causes a violent release of K in 1000–1200 ℃. This can be attributed to the surplus of Si in the system, promoting the release after the eutectic melting between K-silicate and SiO 2 .
研究领域:
能源与环境科学
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材料科学
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产品关联
DOI
高影响因子
Case Studies in Construction Materials
·
2022
·
IF 4.934
Shengjian Lin,Yanjin Zheng,Wenbiao Liu,Hang Ma,Feng Rao,Lang Yang,Shuiping Zhong
Two alkalis of industrial solid wastes, calcium carbide residue-mirabilite (CCRM), were used as a green combined activator to consolidate phosphorus tailings and soluble phosphorus as well as fluorine through the alkaline activation process. The results based on XRD, FTIR, 29 Si NMR and SEM indicated that most of the blast furnace slag (BFS) forms gels to consolidate phosphorus tailings, and the calcium silicate hydrate (C-S-H) gel dominated mechanical properties and immobilization of soluble phosphorus and fluorine. Comparing with the classical alkaline activators Na 2 SiO 3 and NaOH, the CCRM activated materials displayed great competitiveness in mechanical properties with the order of NaOH < CCRM < Na 2 SiO 3 . Its maximum compressive strength reached to 10.9 MPa, and the compressive strength increased greatly with certain increasing content of BFS. In addition, the toxicity characteristic leaching procedure (TCLP) tests found the consolidation of risky soluble fluorine and phosphorus ions in the alkaline activation materials (AAMs) presented in the trend of CCRM > NaSiO 3 > NaOH, and the tendency enlarges with increasing BFS addition, over 93.1 % and 98.9 % of soluble fluorine and phosphorus ions could be well fixed. Considering on the environmental and economic efficiency, mechanical properties, soluble phosphorus and fluorine immobilization, the CCRM is found a quite potential solid waste alkali activator for phosphorus tailings and soluble fluorine & phosphorus solidification.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
ACS Omega
·
2021
·
IF 3.512
Bowei Shen,XueJun Yu,Wenxiu Jiang,Hui Yuan,Mengqi Zhao,Hong Zhou,Zhiquan Pan
This work proposed to prepare solid acid from phosphorus tailings and successfully convert Dioscorea zingiberensis C.H. Wright (DZW) into diosgenin from the perspective of solid waste resource reuse and clean production. The results showed that SiO2–SO3H solid acid could catalyze the production of diosgenin from total saponins under solvothermal reaction conditions. In addition, the parameters of a single factor, such as the amount of SiO2–SO3H, solvent volume, reaction temperature, and reaction time, were optimized to confirm the optimal range of reaction conditions, and the optimal process conditions were determined by the response surface method. The yield of diosgenin was 2.45 ± 0.17% under the optimum conditions, and the yield of diosgenin was increased by 12.90% compared with the traditional acid hydrolysis process. Except the relatively higher catalytic activity, the alcoholysis approach for the production of diosgenin has no waste liquid to discharge. The products were analyzed by high-performance liquid chromatography-mass spectrometry, and the pathway to convert total saponins into diosgenin under SiO2–SO3H has been proposed. Moreover, the adopted catalyst can be prepared with very low cost from phosphorus tailings. Considering the obvious superiorities, the alcoholysis approach in this work could be a promising strategy for green production of diosgenin as well as a possible utilization pathway of phosphorus tailings.
研究领域:
中药化学
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环境科学
·
催化化学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）