Advanced Oxidation Processes and Biotechnological Alternatives for the Treatment of Tannery Wastewater

Abstract

The tannery industry is one of the economic sectors that contributes to the development of different countries. Globally, Europe and Asia are the main producers of this industry, although Latin America and Africa have been growing considerably in recent years. With this growth, the negative environmental impacts towards different ecosystem resources as a result of the discharges of recalcitrated pollutants, have led to different investigations to generate alternative solutions. Worldwide, different technologies have been studied to address this problem, biological and physicochemical processes have been widely studied, presenting drawbacks with some recalcitrant compounds. This review provides a context on the different existing technologies for the treatment of tannery wastewater, analyzing the physicochemical composition of this liquid waste, the impact it generates on human health and ecosystems and the advances in the different existing technologies, focusing on advanced oxidation processes and the use of microalgae. The coupling of advanced oxidation processes with biological processes, mainly microalgae, is seen as a viable biotechnological strategy, not only for the removal of pollutants, but also to obtain value-added products with potential use in the biorefining of the biomass.

Evaluation of the Light/Dark Cycle and Concentration of Tannery Wastewater in the Production of Biomass and Metabolites of Industrial Interest from Microalgae and Cyanobacteria

“…The different toxic compounds in high concentrations and the dark color of the effluent, the product of the different compounds used during the tanning process, can inhibit or minimize growth. Likewise, this prevents the entry of light into the medium and limits the growth of microalgae and cyanobacterium [1,57], which explains the growth rates achieved by the strains of Chlorella sp. and Scenedesmus sp.…”

“…To process these, an average of 10-25 m 3 of clean water is used in the different stages of the tannery process. This process generates a considerable volume of untreated wastewater, which is finally discharged into other bodies of water [1]. These effluents contain a high concentration of contaminating organic matter due to the presence of particles of blood, meat, hair, soluble proteins, and fertilizer.…”

“…Several species belonging to the genera Chlorella, Scenedesmus, Arkistrodesmus, Arthrospira, and Hapalosiphon sp. have been tested for their ability to grow in different types of wastewater [1,19,20]. In these systems, algae transform hazardous nutrients into biomass which can be later used to extract other metabolites, making it an interesting biotechnological tool for use in wastewater treatment [21,22] Another essential characteristic of these microorganisms is their capacity to bioaccumulate heavy metals, which may increase their potential as a sustainable alternative for the treatment of tannery wastewater [23][24][25].…”

In situ green synthesis of copper(ii) oxide (CuO) and maleic anhydride grafted polypropylene (PP-MAH) for highly efficient nanocatalysis in tannery wastewater treatment

“…Issues such as secondary pollution arising from solid waste, the financial implications of the procedures involved, and low BOD/COD reduction dampen their practical applicability in real-world scenarios. 7 In response to the challenges above, scientists have actively pursued innovative and economically viable technologies. This study delves into the pivotal role played by metal/metal oxide nanoparticle-based nanocomposites in mitigating the BOD and COD of tannery wastewater.…”

Phytoremediation of chromium, iron and nickel by Indian Rice Plant (Oryza sativa L.): An opportunity for management of multi-metal contaminated tannery wastewaterPhytoremediation of chromium, iron and nickel by Indian Rice Plant (Oryza sativa L.): An opportunity for management of multi-metal contaminated tannery wastewater

“…The released wastewater is characterized by high odors due to the presence of free ammonia, volatile organic compounds, and hydrogen sulphide (Senatore et al 2021). Tannery wastewater (TWW) also has a high level of potentially toxic heavy metals (PTHMs) like Cr, Cd, etc., this mixture of heavy metals makes the tannery wastewater, problematic for the environment (Urbina-Suarez et al 2021;Ahmed et al 2022). Water/soil contaminated with these toxic heavy metals has become a worldwide concern due to their non-specific toxicity and longlasting exposure to the environment.…”