Recycling electro-coagulated sludge from textile wastewater treatment plants as an adsorbent for the adsorptions of fluoride in an aqueous solution

Abstract

Iron-based oxides and hydroxides from the EC sludge were recovered and prepared for fluoride ion adsorption. EC sludge as an iron-based adsorbent was synthesized by thermal activation at 500 C. Iron oxide adsorbents could efficiently remove fluoride ions from synthetically prepared water solutions. The adsorption of fluoride followed a Langmuir isotherm pseudo-Second-order kinetic model. The prepared adsorbents were regenerated in an aqueous solution and the reusability efficiency was up to the 4th cycle.

Treatment of fluorinated wastewater with chitosan modified activated sludge lysis ash

“…The supernatant was passed through a 0.45 mm lter membrane aer 30 minutes of standing, and the concentration of uoride ions in the reaction solution was determined using a uoride ion electrode. In batch adsorption experiments, the effects of initial uorine concentration (1, 2, 4, 6, 10 and 20 mg L −1 ), reaction time (10-340 min), solution pH (2)(3)(4)(5)(6)(7)(8)(9)(10)(11) and the amount of adsorbent (0.1, 0.3, 0.5, 0.7, 0.9, 1.0 and 1.1 g/100 mL) were separately considered. The amount of uorine adsorbed and the uoride removal rate were calculated as follows:…”

“…Industrial and agricultural waste is now widely used for the removal of heavy metals, dyes and other pollutants from water. 5,6 Studies have verified that straw ash, 7 electrocoagulated (EC) sludge, 8 modified clay composite materials, 9 high-temperature modified eggshells, 10 and crushed clay pots 11 show promise in fluoride removal. Meanwhile, activated sludge also can be used as a good adsorption material with the advantages of low price, high efficiency, good selectivity, and a wide applicability range of pH and temperature, 12,13 but there is a lack of reported studies related to the use of activated sludge lysis ash as a fluoride adsorption material.…”

Facile fabrication of low-cost activated carbon bonded polyethersulfone membrane for efficient bacteria and turbidity removal

“…Different methods, e.g., adsorption (Aghababaei et al 2021;Aragaw 2021) and membrane filtration (Davari et al 2021;Mahmoud & Kochameshki 2021) have been used for the water treatment process. In terms of adsorption, adsorbents for wastewater treatments are made of many materials, such as activated carbon (Belhamdi et al 2020), hydroxyapatite (Hariyanto et al 2020), polymers (Lou et al 2021), zeolites (Konale et al 2020), and clay (Ntwampe 2020).…”