Study on Leaching of Phosphate from Municipal Wastewater Treatment Plant’s Sewage Sludge and Followed by Adsorption on Mg‐Al Layered Double Hydroxide

Abstract

Sewage sludge from municipal wastewater treatment plant was a rich phosphorus resource. In this study, HCl, H2SO4, and HNO3 were investigated as leaching acids for extraction of phosphate from the sludge to recover this value nutrient by adsorption using layered double hydroxide (LDH) nanomaterial. Mg-Al LDH was synthesized by coprecipitation at room temperature and at a constant pH of 10 (±0.5) with Mg/Al molar ratio of 2.0. The material was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer-Emmet-Teller (BET), and Fourier transform infrared spectroscopy (FTIR) and then was used to adsorb phosphate leaching from the sewage sludge. Adsorption experiments were carried out as a function of adsorbent dose, phosphate initial concentrations, and pH. The adsorption isotherm data fitted the Langmuir model perfectly. The high adsorption capacity of Mg-Al LDH and slowly released phosphate of the post-adsorption LDH suggested that this material was an excellent adsorbent for phosphate recovery and could be considered as a potential phosphate release fertilizer.

Phosphorus recovery from hydrothermal carbonization of organic waste: a review

“…101 Based on the data presented in Tables 3 and 4, it can be deduced that acid treatment of hydrochar allows for a significant recovery of P that can reach 100% depending on the utilized acid, and that can mainly be attributed to the effect of increasing H + activity on the solubility of P. High acid concentrations tend to increase the efficiency of P extraction from hydrochar, while HCl and citric acid appear to be the most effective among different acids. These findings agree with the experimental results of Phuong et al (2022), where the efficiency of different acids in P-leaching was assessed. Their results showed that, for samples with moderately high moisture levels, the increase in acid concentration for HCl and H 2 SO 4 leads to a significant increase in P-leaching.…”

“…(2022), where the efficiency of different acids in P‐leaching was assessed. Their results showed that, for samples with moderately high moisture levels, the increase in acid concentration for HCl and H 2 SO 4 leads to a significant increase in P‐leaching 116 …”

“…Their results showed that, for samples with moderately high moisture levels, the increase in acid concentration for HCl and H 2 SO 4 leads to a significant increase in P-leaching. 116 An alternative to acid extraction of P from hydrochar can be presented by altering the initial conditions of HTC to increase the pool of readily available P in the solid product. In this way, the hydrochar can qualify as a STUBIAS fertilizer, which can be directly applied without the need for further treatment.…”

Synthesis, Spectroscopic Evaluations and UV-Vis Titration Studies of New Symmetrical Amide Compounds Derived from N-6-[(4-pyridylmethylamino)carbonyl]-pyridine-2-carboxylic Acid Methyl Ester

“…Several phosphate detection techniques, such as spectrophotometry, fluorometry and chromatography, are available. However, their time-consuming, labor-intensive and costly characteristics, dependence on skilled operators and hazardous chemicals, make them inappropriate for monitoring purposes [3,4]. Separation or isolation of large radii anions from water such as phosphate requires other suitable materials that are unavailable.…”