![]() To enhance the adsorption capacity of biochar, some efforts have been made to modify biochar, which has the favorable advantage of developing loading metal with more binding sites ( Wang et al. Metal ions in sewage sludge mainly exist as cations, limiting the adsorption ability of biochar ( Yu et al. The ion exchange groups on the surface of the biochar, predominantly negatively charged, are decreased by the severe thermal treatment during the process of pyrolysis. In the past few years, special attention has been paid to converting sewage sludge to biochar through a pyrolysis process. It can not only realize the resource utilization of sewage sludge, but also obtain good economic benefit and social benefit ( Barry et al. However, sewage sludge also can be carbonized to synthesize biochar because of its great content of biomass and organic matter. In the previous studies on adsorption of antibiotics by biochars, many scientists focused on the adsorption effect of lignocellulosic biochar. Compared with the direct incineration and other treatment methods, the cost and energy consumption of biochar preparation are lower and the treatment method is more environmentally friendly and hygienic. The feedstocks of biochar production are a large number of low-cost organic wastes, such as agricultural wastes, garden residues, sewage sludge and algae. Also, these unique physicochemical properties make biochar attract increasing attention as a promising adsorbent and supporting matrix to remove organic contaminants, heavy metals and other inorganic contaminants from wastewater ( Ahmad et al. It has been considered as compost additives and soil amendments due to its large specific surface area, porous structure and high ion exchange capacity. Therefore, it is desirable to explore an efficient and feasible method for sewage sludge treatment.īiochar, a porous, stable and carbon-rich solid material, is produced by thermal decomposition or pyrolysis with little or no oxygen. It has become one of the most urgent environmental issues to dispose of sewage sludge safely and properly with up to 60% of the total cost spent on these processes for wastewater treatment ( Yan et al. ![]() If sewage sludge is used for incineration, dioxins and other highly toxic substances are produced with burning. Sewage sludge used for landfill easily to decays, goes off and produces smelly gas with water seeping into groundwater ( Bondarczuk et al. However, if untreated sewage sludge is applied to land, it will pose potential dangers to human health. Sewage sludge is applied to increase soil fertility and improve soil structure in agriculture commonly owing to its being rich in N, P and other nutrients. Traditional sewage sludge treatment techniques include use in agriculture, landfill and incineration ( Rigby et al. Sewage sludge is a mixture of fibers, animal and plant residues, microorganisms, pathogens and heavy metals. With the continuous development of urbanization and industrialization, all sewage plants in China produced 30 million tons of sewage sludge in 2013, expected to reach 60–90 million tons by 2020 ( Lin et al. The study can not only solve the problems associated with the pollution of antibiotics from wastewater, but also reduced the treatment pressure of sewage sludge effectively. Furthermore, the main mechanism of antibiotics adsorption by metal loaded sewage sludge biochars might be pores filling, Van der Waals forces and H-bonding. The maximum adsorption amount of TC, SMZ and AMC could reach 123.35, 99.01 and 109.89 mg/g by BC-Fe. Intra-particle diffusion and Langmuir models were more suitable to describe the adsorption process. BC-Fe, BC-Al and BC-Mn possessed rougher surfaces, larger specific surface area and better pore structure. Fe loaded sewage sludge biochar (BC-Fe), Al loaded sewage sludge biochar (BC-Al) and Mn loaded sewage sludge biochar (BC-Mn) were characterized and used to explore the performance of adsorbing tetracycline (TC), sulfamethoxazole (SMZ) and amoxicillin (AMC). ![]() Three metal ions were selected to modify sewage sludge biochar through the pyrolysis with the metal loaded method. ![]() Application of sewage sludge biochar as an adsorbent for antibiotics treatment has obtained special attention owning to its low cost and surface functionality. ![]()
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