Currently, a serious threat for living organisms and human life in particular, is water contamination with persistent organic and inorganic pollutants. To date, several techniques have been adopted to remove/treat organics and toxic contaminants. Adsorption is one of the most effective and economical methods for this purpose. Generally, porous materials are considered as appropriate adsorbents for water purification. Conventional adsorbents such as activated carbons have a limited possibility of surface modification (texture and functionality), and their adsorption capacity is difficult to control. Therefore, despite the significant progress achieved in the development of the systems for water remediation, there is still a need for novel adsorptive materials with tunable functional characteristics. This review addresses the new trends in the development of new adsorbent materials. Herein, modern carbon-based materials, such as graphene, oxidized carbon, carbon nanotubes, biomass-derived carbonaceous matrices—biochars as well as their composites with metal-organic frameworks (MOFs) and MOF-derived highly-ordered carbons are considered as advanced adsorbents for removal of hazardous organics from drinking water, process water, and leachate. The review is focused on the preparation and modification of these next-generation carbon-based adsorbents and analysis of their adsorption performance including possible adsorption mechanisms. Simultaneously, some weak points of modern carbon-based adsorbents are analyzed as well as the routes to conquer them. For instance, for removal of large quantities of pollutants, the combination of adsorption and other methods, like sedimentation may be recommended. A number of efficient strategies for further enhancing the adsorption performance of the carbon-based adsorbents, in particular, integrating approaches and further rational functionalization, including composing these adsorbents (of two or even three types) can be recommended. The cost reduction and efficient regeneration must also be in the focus of future research endeavors. The targeted optimization of the discussed carbon-based adsorbents associated with detailed studies of the adsorption process, especially, for multicomponent adsorbate solution, will pave a bright avenue for efficient water remediation.

Modern Carbon-Based Materials for Adsorptive Removal of Organic and Inorganic Pollutants from Water and Wastewater.

Adsorption of a wide variety of antibiotics on graphene-based nanomaterials: A modelling study.

Recent advances in eco-friendly composites derived from lignocellulosic biomass for wastewater treatment

Next-generation graphene oxide additives composite membranes for emerging organic micropollutants removal: Separation, adsorption and degradation.

With the aim to present an alternative material that can be used in adsorption/degradation processes to remove pharmaceutical pollutants present in water, a biocarbon was designed from Melia Azedarach stones. Material has a high surface area (1230 m2 g−1) with mainly oxygenated groups; these properties give it exceptional characteristics for removing Atenolol. To show the versatility of the material, the adsorption of Atenolol in different water matrices was tested: Ultrapure water (0 mg L−1 CaCO3), solution model (200 mg L−1 CaCO3), and tap water from Lisbon city (80 mg L−1 CaCO3). The pseudo-second-order model can well describe the adsorption kinetics; kinetic constants obtained were: 75.70, 46.18, and 42.58 g mmol h−1, respectively. The adsorption isotherms are correctly described by the Langmuir model, obtaining maximum adsorption capacities of 1.83, 2.00, and 1.81 mmol g−1, respectively. Physisorption phenomena carry out the adsorption mechanism (E < 1 kJ mol−1) between the atenolol molecule, positively charged, and the material's surface, negatively charged, forming a monolayer onto the material's surface. Once the material was saturated, its regeneration was studied by employing thermal treatment at 450 °C. Results show a decrease in the surface area after treatment, resulting in a loss of adsorption capacity (30 %). This procedure makes it possible to achieve repeat cycles of adsorption-degradation until the adsorbent is completely exhausted. The results obtained show this new material as a promising adsorbent for wastewater treatment contaminated with pharmaceutical pollutants since it has higher adsorption capacities than those reported in the literature in different water matrices. 

Klaudija Ivanković

Papers

Modelling of the adsorption of pharmaceutically active compounds on carbon-based nanomaterials.

Multiclass determination of drug residues in water and fish for bioaccumulation potential assessment.