Application of Sludge-Based Activated Carbons for the Effective Adsorption of Neonicotinoid Pesticides

Abstract

The amount of sludge produced in wastewater treatment plants (WWTPs) has increased over the years, and the methods used to reduce this waste, such as incineration, agricultural use, or disposal in landfills, cause problems of secondary pollution. For this reason, it is necessary to find sustainable and low-cost solutions to manage this waste. Additionally, emerging and priority pollutants are attracting attention from the scientific community as they can generate health problems due to inadequate removal in conventional WWTPs. In this work, a pharmaceutical industry sludge was used as a precursor in the synthesis of four activated carbons (ACs) using different activating agents (ZnCl2, FeCl3∙6H2O, Fe(NO3)3∙9H2O, and Fe(SO4)3∙H2O), to be used for the removal by adsorption of three neonicotinoid pesticides included in latest EU Watch List (Decision 2018/840): acetamiprid (ACT), thiamethoxam (THM), and imidacloprid (IMD). The prepared ACs showed micro–mesoporous properties, obtaining relatively slow adsorption kinetics to reach equilibrium, but despite this, high values of adsorption capacity (qe) were obtained. For example, for AC-ZnCl2 (SBET = 558 m2/g), high adsorption capacities of qe = 128.9, 126.8, and 166.1 mg/g for ACT, THM, and IMD, respectively, were found. In most cases, the adsorption isotherms showed a multilayer profile, indicating an important contribution of the mesoporosity of the activated carbons in the adsorption process.

Recovery, regeneration and sustainable management of spent adsorbents from wastewater treatment streams: A review

“…Sludges resulting from industrial and municipal wastewater treatment can either be used with simple processing (Maqbool et al, 2016) or by using modifications, such as carbonisation/activation (Sanz-Santos et al, 2021), for usage in pollutant removal from aqueous sources (Devi and Saroha 2017). Pharmaceutical industry sludge, activated with various activating agents [ZnCl2, FeCl3.6H2O, Fe(NO3)3.9H2O, and Fe(SO4)3.H2O,] was used for trapping 3 different pesticides, and it showed adsorption capacities of 129 mg/g (acetamiprid), 127 mg/g (thiamethoxam), and 166 mg/g (imidacloprid) with 1.5 g/L dosage and 50 mg/L pollutant concentration for ZnCl2-activated sludge (Sanz-Santos et al, 2021).…”

ZnO2‐Based Carbon Composite Doped with Sulphur for the Removal of Highly Toxic Thiamethoxam from Wastewater

“…Magnetic nanomodified activated carbon 42.44 [52] Granular activated carbon 60.00 [53] Magnetic copper-based metal-organic framework 2.88 [54] Nano water treatment residual 50.00 [55] Bulk water treatment residual 19.15 [55] Pristine MWCNT 38.18 [56] Functionalized MWCNTs 95.43 [56] Metal Hexa-cyanoferrate nanoparticles of Zn, Cu, Ni and Co 111.98, 106.61, 105.26 and 104.60 [5] AC-ZnCl 2 126.8 [57] AC-FeCl 3 81.1 [57] Filter Cake Biochar 10.17 [58] Boric Acid modified biochar 137.46 [46] ZnO 2 -based carbon composite 142.86 This Study…”

Phragmites australis (Reed) as an Efficient, Eco-Friendly Adsorbent for Brackish Water Pre-Treatment in Reverse Osmosis: A Kinetic Study

“…Many research papers concerning using worthless materials to prepare carbon-based adsorbents for water treatment were published, such as sewage sludge, peat, activated carbon from biomass waste, etc. [ 8 ]. Based on the same considerations, this study will utilize the Phragmites australis (reed) that is the most abundant and dangerous in swamp ecosystems as a new worthless biomass by demonstrating its adsorption performance and process for both sodium remediation from aquatic environments (groundwater and brackish water) and the management of reed harvesting from the constructed wetland.…”