Computational optimization of bioadsorbents for the removal of pharmaceuticals from water

authors	Pereira, JM; Calisto, V; Santos, SM
nationality	International
journal	JOURNAL OF MOLECULAR LIQUIDS
author keywords	Adsorption; Water treatment; Molecular dynamics; Molecular modelling; Monte-Carlo simulations; Virtual porous carbons
keywords	PAPER-MILL SLUDGE; ACTIVATED CARBONS; WASTE-WATER; ADSORPTION; ADSORBENTS; EFFLUENT; SURFACE; WOOD; ANTIBIOTICS; PYROLYSIS
abstract	Pharmaceutically active ingredients are among the most persistent wastewater contaminants, resisting to wastewater treatment plants (WWTP) conventional processes, and some of them are proved to pose serious threats to organisms and the environment. In this context, adsorption by activated carbons (AC) is one of the most promising methodologies for the removal of pharmaceuticals from water due to its versatility and high removal efficiency. However, ACs are expensive and therefore not widely applied in WWTP. Primary sludge from paper mills has been previously appointed as a potential inexpensive and renewable source of carbon for AC production by pyrolysis. Computational chemistry may help shed some light into the molecular mechanisms underlying the adsorption of organic pollutants onto ACs. In this context, CarbGen, an online tool for Virtual Porous Carbon (VPC) models creation, was developed and made available for public use. A quantitatively validated model based on both physical and chemical characteristics of an experimentally produced AC is proposed. The produced model is in agreement with obtained experimental data in terms of elemental composition, functional group content and surface area. Grand Canonical Monte Carlo (GCMC) studies were performed on various VPC models with different levels of oxygen content, revealing the importance of electrostatic mechanisms in adsorption, with different degrees depending on the pharmaceutical molecular characteristics. The results further reinforce the importance of functional groups in future VPC models for correct molecular modelling. (C) 2019 Elsevier B.V. All rights reserved.
publisher	ELSEVIER SCIENCE BV
issn	0167-7322
isbn	1873-3166
year published	2019
volume	279
beginning page	669
ending page	676
digital object identifier (doi)	10.1016/j.molliq.2019.01.167
web of science category	Chemistry, Physical; Physics, Atomic, Molecular & Chemical
subject category	Chemistry; Physics
unique article identifier	WOS:000462101800070