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Li Q, Sun D, Hua J, Jiang K, Xu Z, Tong K. Enhancing low-temperature thermal remediation of petroleum sludge by solvent deasphalting. CHEMOSPHERE 2022; 304:135278. [PMID: 35697105 DOI: 10.1016/j.chemosphere.2022.135278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/18/2022] [Accepted: 06/05/2022] [Indexed: 06/15/2023]
Abstract
Thermal treatment is a promising technique for treating petroleum sludge (PS). However, asphaltenes as a recalcitrant fraction of PS induce strong bounding between petroleum and minerals, and therefore lead to the need for high temperature and hence high energy consumption in thermal treatment of PS. In this study, a novel method combining a deasphalting pretreatment of PS with low-temperature thermal desorption (LTTD) was developed. The efficiency of deasphalting was found to be positively correlated to the ability of n-alkanes and asphaltene dispersants in dispersing asphaltenes. In treating six different kinds of PS, the residual oil contents were all below 2.5% after the deasphalting alone. Compared with direct thermal desorption at 600 °C for 1 h, dodecyl benzene sulfonic acid (DBSA)-assisted heptane deasphalting made thermal desorption at 350 °C for 1 h sufficient to treat these APS. The residual oil content of sludge after LTTD is lower than 0.45%. FT-IR, Raman spectra and XPS analysis confirmed that the carbon residue in APS after LTTD is primarily graphite state, which is extremely stable and does not migrate to the surrounding environment as compared with the crude oil in the APS. Hence, solvent deasphalting results in effective treatment of PS by LTTD, while the solvent can be recycled by distillation and crude oil recovered as value-added petroleum resource. The LTTD represents therefore a novel green strategy for treating PS and resource utilization.
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Affiliation(s)
- Qi Li
- Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Shandong University, Jinan, Shandong, 250100, PR China
| | - Dejun Sun
- Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Shandong University, Jinan, Shandong, 250100, PR China.
| | - Jifei Hua
- Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Shandong University, Jinan, Shandong, 250100, PR China
| | - Kai Jiang
- Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Shandong University, Jinan, Shandong, 250100, PR China
| | - Zhenghe Xu
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, PR China; Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Kun Tong
- State Key Laboratory of Petroleum Pollution Control, Beijing, 102206, China
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Synthesis and Characterization of N and Fe-Doped TiO2 Nanoparticles for 2,4-Dimethylaniline Mineralization. NANOMATERIALS 2022; 12:nano12152538. [PMID: 35893506 PMCID: PMC9331849 DOI: 10.3390/nano12152538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 02/01/2023]
Abstract
The present study aimed to evaluate the feasibility of developing low-cost N- and Fe-doped TiO2 photocatalysts for investigating the mineralization of 2,4-dimethylaniline (2,4-DMA). With a single anatase phase, the photocatalysts showed high thermal stability with mass losses of less than 2%. The predominant oxidative state is Ti4+, but there is presence of Ti3+ associated with oxygen vacancies. In materials with N, doping was interstitial in the NH3/NH4+ form and for doping with Fe, there was a presence of Fe-Ti bonds (indicating substitutional occupations). With an improved band gap energy from 3.16 eV to 2.82 eV the photoactivity of the photocatalysts was validated with an 18 W UVA lamp (340–415 nm) with a flux of 8.23 × 10−6 Einstein s−1. With a size of only 14.45 nm and a surface area of 84.73 m2 g−1, the photocatalyst doped with 0.0125% Fe mineralized 92% of the 2,4-DMA in just 180 min. While the 3% N photocatalyst with 12.27 nm had similar performance at only 360 min. Factors such as high surface area, mesoporous structure and improved Ebg, and absence of Fe peak in XPS analysis indicate that doping with 0.0125% Fe caused a modification in TiO2 structure.
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Hydrothermal and Co-Precipitated Synthesis of Chalcopyrite for Fenton-like Degradation toward Rhodamine B. Catalysts 2022. [DOI: 10.3390/catal12020152] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
In this study, Chalcopyrite (CuFeS2) was prepared by a hydrothermal and co-precipitation method, being represented as H-CuFeS2 and C-CuFeS2, respectively. The prepared CuFeS2 samples were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive X-ray spectroscopy mapping (EDS-mapping), powder X-ray diffractometer (XRD), X-ray photoelectron spectrometry (XPS), and Raman microscope. Rhodamine B (RhB, 20 ppm) was used as the target pollutant to evaluate the degradation performance by the prepared CuFeS2 samples. The H-CuFeS2 samples (20 mg) in the presence of Na2S2O8 (4 mM) exhibited excellent degradation efficiency (98.8% within 10 min). Through free radical trapping experiment, the major active species were •SO4− radicals and •OH radicals involved the RhB degradation. Furthermore, •SO4− radicals produced from the prepared samples were evaluated by iodometric titration. In addition, one possible degradation mechanism was proposed. Finally, the prepared H-CuFeS2 samples were used to degrade different dyestuff (rhodamine 6G, methylene blue, and methyl orange) and organic pollutant (bisphenol A) in the different environmental water samples (pond water and seawater) with 10.1% mineral efficiency improvement comparing to traditional Fenton reaction.
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