Combination of a Highly Efficient Biological System and Visible-Light Photocatalysis Pretreatment System for the Removal of Phthalate Esters from Wastewater
To save energy and increase treatment efficiency, a visible-light photocatalysis system was coupled with a biological treatment system for the continuous removal of phthalate esters (PAEs) from synthetic wastewater. Di-(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), and dimethyl phthalate...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-10-01
|
| Series: | Water |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4441/14/19/3139 |
| _version_ | 1797476417737326592 |
|---|---|
| author | Chih-Yu Chen Guey-Horng Wang Yu-Jen Chang Yi-Hui Chen Chiu-Yu Cheng Ying-Chien Chung |
| author_facet | Chih-Yu Chen Guey-Horng Wang Yu-Jen Chang Yi-Hui Chen Chiu-Yu Cheng Ying-Chien Chung |
| author_sort | Chih-Yu Chen |
| collection | DOAJ |
| description | To save energy and increase treatment efficiency, a visible-light photocatalysis system was coupled with a biological treatment system for the continuous removal of phthalate esters (PAEs) from synthetic wastewater. Di-(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), and dimethyl phthalate (DMP) were treated using an iodine-doped TiO<sub>2</sub> photocatalyst, and the reactions followed first-order kinetics (similar to ultraviolet TiO<sub>2</sub> photocatalysis) to produce phthalic acid as an intermediate product. The effects of various operating factors, such as PAE concentrations, pH, light intensity, retention time (RT), and the coexistence of PAEs, on individual PAE removal were investigated. DEHP-degrading bacteria were isolated from DEHP-contaminated soil, purified through serial dilution, and then identified through DNA sequencing. The results indicated that the optimal operating conditions for PAE removal with a visible-light photoreactor were a pH of 5, a temperature of 30 °C, a light intensity of 300 W, and an RT of 5.5 min. DEHP, which contains long and branched chains, was more difficult to degrade than DMP, which contains short alkyl side chains. <i>Pseudomonas</i> sp. was the most dominant bacteria in the DEHP-contaminated soil and was inoculated in a packed bed reactor (PBR) for complete PAE degradation. The effluent containing PAEs was pretreated using the visible-light photoreactor under a short RT. This treatment resulted in the effluent becoming biodegradable, and PAEs could be completely removed from the treated effluent by using the PBR. The coupled photobiological system achieved removal efficiencies of 99.6%, 99.9%, and 100% for DEHP, DBP, and DMP, respectively, during the continuous treatment. The results of this study indicate that the developed coupled system is an effective, energy-saving, and cost-efficient tool for treating wastewater containing PAEs. |
| first_indexed | 2024-03-09T20:58:26Z |
| format | Article |
| id | doaj.art-80112b9fbef0475e9be07266ad2e6f95 |
| institution | Directory Open Access Journal |
| issn | 2073-4441 |
| language | English |
| last_indexed | 2024-03-09T20:58:26Z |
| publishDate | 2022-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Water |
| spelling | doaj.art-80112b9fbef0475e9be07266ad2e6f952023-11-23T22:16:22ZengMDPI AGWater2073-44412022-10-011419313910.3390/w14193139Combination of a Highly Efficient Biological System and Visible-Light Photocatalysis Pretreatment System for the Removal of Phthalate Esters from WastewaterChih-Yu Chen0Guey-Horng Wang1Yu-Jen Chang2Yi-Hui Chen3Chiu-Yu Cheng4Ying-Chien Chung5Department of Tourism and Leisure, Hsing Wu University, New Taipei City 244012, TaiwanResearch Center of Natural Cosmeceuticals Engineering, Xiamen Medical College, Xiamen 361008, ChinaDepartment of Biological Science and Technology, China University of Science and Technology, Taipei City 115311, TaiwanDepartment of Biological Science and Technology, China University of Science and Technology, Taipei City 115311, TaiwanDepartment of Biological Science and Technology, China University of Science and Technology, Taipei City 115311, TaiwanDepartment of Biological Science and Technology, China University of Science and Technology, Taipei City 115311, TaiwanTo save energy and increase treatment efficiency, a visible-light photocatalysis system was coupled with a biological treatment system for the continuous removal of phthalate esters (PAEs) from synthetic wastewater. Di-(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), and dimethyl phthalate (DMP) were treated using an iodine-doped TiO<sub>2</sub> photocatalyst, and the reactions followed first-order kinetics (similar to ultraviolet TiO<sub>2</sub> photocatalysis) to produce phthalic acid as an intermediate product. The effects of various operating factors, such as PAE concentrations, pH, light intensity, retention time (RT), and the coexistence of PAEs, on individual PAE removal were investigated. DEHP-degrading bacteria were isolated from DEHP-contaminated soil, purified through serial dilution, and then identified through DNA sequencing. The results indicated that the optimal operating conditions for PAE removal with a visible-light photoreactor were a pH of 5, a temperature of 30 °C, a light intensity of 300 W, and an RT of 5.5 min. DEHP, which contains long and branched chains, was more difficult to degrade than DMP, which contains short alkyl side chains. <i>Pseudomonas</i> sp. was the most dominant bacteria in the DEHP-contaminated soil and was inoculated in a packed bed reactor (PBR) for complete PAE degradation. The effluent containing PAEs was pretreated using the visible-light photoreactor under a short RT. This treatment resulted in the effluent becoming biodegradable, and PAEs could be completely removed from the treated effluent by using the PBR. The coupled photobiological system achieved removal efficiencies of 99.6%, 99.9%, and 100% for DEHP, DBP, and DMP, respectively, during the continuous treatment. The results of this study indicate that the developed coupled system is an effective, energy-saving, and cost-efficient tool for treating wastewater containing PAEs.https://www.mdpi.com/2073-4441/14/19/3139photocatalysisphthalate esterspacked bed reactortitanium dioxide |
| spellingShingle | Chih-Yu Chen Guey-Horng Wang Yu-Jen Chang Yi-Hui Chen Chiu-Yu Cheng Ying-Chien Chung Combination of a Highly Efficient Biological System and Visible-Light Photocatalysis Pretreatment System for the Removal of Phthalate Esters from Wastewater Water photocatalysis phthalate esters packed bed reactor titanium dioxide |
| title | Combination of a Highly Efficient Biological System and Visible-Light Photocatalysis Pretreatment System for the Removal of Phthalate Esters from Wastewater |
| title_full | Combination of a Highly Efficient Biological System and Visible-Light Photocatalysis Pretreatment System for the Removal of Phthalate Esters from Wastewater |
| title_fullStr | Combination of a Highly Efficient Biological System and Visible-Light Photocatalysis Pretreatment System for the Removal of Phthalate Esters from Wastewater |
| title_full_unstemmed | Combination of a Highly Efficient Biological System and Visible-Light Photocatalysis Pretreatment System for the Removal of Phthalate Esters from Wastewater |
| title_short | Combination of a Highly Efficient Biological System and Visible-Light Photocatalysis Pretreatment System for the Removal of Phthalate Esters from Wastewater |
| title_sort | combination of a highly efficient biological system and visible light photocatalysis pretreatment system for the removal of phthalate esters from wastewater |
| topic | photocatalysis phthalate esters packed bed reactor titanium dioxide |
| url | https://www.mdpi.com/2073-4441/14/19/3139 |
| work_keys_str_mv | AT chihyuchen combinationofahighlyefficientbiologicalsystemandvisiblelightphotocatalysispretreatmentsystemfortheremovalofphthalateestersfromwastewater AT gueyhorngwang combinationofahighlyefficientbiologicalsystemandvisiblelightphotocatalysispretreatmentsystemfortheremovalofphthalateestersfromwastewater AT yujenchang combinationofahighlyefficientbiologicalsystemandvisiblelightphotocatalysispretreatmentsystemfortheremovalofphthalateestersfromwastewater AT yihuichen combinationofahighlyefficientbiologicalsystemandvisiblelightphotocatalysispretreatmentsystemfortheremovalofphthalateestersfromwastewater AT chiuyucheng combinationofahighlyefficientbiologicalsystemandvisiblelightphotocatalysispretreatmentsystemfortheremovalofphthalateestersfromwastewater AT yingchienchung combinationofahighlyefficientbiologicalsystemandvisiblelightphotocatalysispretreatmentsystemfortheremovalofphthalateestersfromwastewater |