Zhifu Tian , Huilin Wan , Ruotong Jin , Xiaojie Qiu , Bibek Bamanu , Yingxin Zhao
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引用次数: 0
Abstract
The exploitation of efficient sludge-derived biochar (SBC) is of great significance for the oxidative degradation of pollutants and resource recovery of waste. This study innovatively synthesized deashed biochar (DBC) by pyrolyzing municipal sludge followed by an acid washing process using a mixture of 10% hydrofluoric acid and 1 M hydrochloric acid. The mixed-acid treatment removed inorganic minerals from biochar, obviously improving the specific surface area (from 81.909 m2/g to 405.794 m2/g), average pore size (from 5.513 nm to 7.412 nm), and surface functional group content of the biochar. The DBC was utilized to activate peroxymonosulfate (PMS) for degrading sulfamethoxazole (SMX). It demonstrated markedly improved performance compared to the SBC. 59.1% of SMX was adsorbed in initial 30 min, and > 95% of SMX was degraded within the subsequent 20 min following PMS addition. Furthermore, DBC had high catalytic activity across a broad pH range, while its performance was hindered by HCO3−. Mechanism analysis indicated that the effective degradation of SMX in SBC800/PMS and DBC/PMS systems was mainly achieved through a non-radical pathway dominated by singlet oxygen (1O2). The CO, graphitic N, and pyridinic N on DBC induced the formation of electron-deficient site C(+), facilitating effective extraction of electrons from PMS, thus enhancing the production of 1O2. This study provides a new perspective for addressing the issue of low catalytic activity in biochar derived from high-ash sludge.
期刊介绍:
The Journal of Water Process Engineering aims to publish refereed, high-quality research papers with significant novelty and impact in all areas of the engineering of water and wastewater processing . Papers on advanced and novel treatment processes and technologies are particularly welcome. The Journal considers papers in areas such as nanotechnology and biotechnology applications in water, novel oxidation and separation processes, membrane processes (except those for desalination) , catalytic processes for the removal of water contaminants, sustainable processes, water reuse and recycling, water use and wastewater minimization, integrated/hybrid technology, process modeling of water treatment and novel treatment processes. Submissions on the subject of adsorbents, including standard measurements of adsorption kinetics and equilibrium will only be considered if there is a genuine case for novelty and contribution, for example highly novel, sustainable adsorbents and their use: papers on activated carbon-type materials derived from natural matter, or surfactant-modified clays and related minerals, would not fulfil this criterion. The Journal particularly welcomes contributions involving environmentally, economically and socially sustainable technology for water treatment, including those which are energy-efficient, with minimal or no chemical consumption, and capable of water recycling and reuse that minimizes the direct disposal of wastewater to the aquatic environment. Papers that describe novel ideas for solving issues related to water quality and availability are also welcome, as are those that show the transfer of techniques from other disciplines. The Journal will consider papers dealing with processes for various water matrices including drinking water (except desalination), domestic, urban and industrial wastewaters, in addition to their residues. It is expected that the journal will be of particular relevance to chemical and process engineers working in the field. The Journal welcomes Full Text papers, Short Communications, State-of-the-Art Reviews and Letters to Editors and Case Studies