Implications for public health demands alternatives to inorganic and synthetic flocculants: bioflocculants as important candidates

Abstract

Chemical flocculants are generally used in drinking water and wastewater treatment due to their efficacy and cost effectiveness. However, the question of their toxicity to human health and environmental pollution has been a major concern. In this article, we review the application of some chemical flocculants utilized in water treatment, and bioflocculants as a potential alternative to these chemical flocculants. To the best of our knowledge, there is no report in the literature that provides an up‐to‐date review of the relevant literature on both chemical flocculants and bioflocculants in one paper. As a result, this review paper comprehensively discussed the various chemical flocculants used in water treatment, including their advantages and disadvantages. It also gave insights into bioflocculants production, challenges, various factors influencing their flocculating efficiency and their industrial applications, as well as future research directions including improvement of bioflocculants yields and flocculating activity, and production of cation‐independent bioflocculants. The molecular biology and synthesis of bioflocculants are also discussed.

Optimization of Cellulase and Xylanase Production by Micrococcus Species under Submerged Fermentation

“…The pH of the fermentation medium is reported to impact the growth of any microbial strain and consequent metabolic product formation [54]. In addition, many enzymatic processes and the transport of various components across the cell membrane are strongly affected by the pH of the medium [55].…”

Assessment of Bacillus pumilus Isolated from Fresh Water Milieu for Bioflocculant Production

“…The pH of the reaction mixture in a flocculation process is one of the key factors that determine flocs formation and the stability of suspended particles [72]. Furthermore, this shows that the ionization of the functional groups in the molecular chain of the bioflocculant is pH-dependent [73].…”

A novel efficient bioflocculant QZ-7 for the removal of heavy metals from industrial wastewater

“…For survival, fresh drinking water must be accessible to all living organisms on the planet. 1,2 Increasing world population, developing industries, and long droughts decrease the available water resources. 3 Inefficient treatment of industrial wastewater results in the contamination of natural water resources by high level of refractory pollutants.…”

“…However, regardless of the signicant effectiveness of the occulating practices in water treatment, the main disadvantage of occulation is the production of breakable ocs at low temperatures; these ocs can scatter the applied physical force. 1 Therefore, "green technology" bioocculants have attracted increasing methodical and technical consideration in environmental wastewater treatment because they are non-hazardous to humans, possess biodegradable constituents, and become free from pollutants by intermediate deprivation. 19 In addition, bioocculants have been generally involved in different applications, such as cleaning up of wastewater, decontamination of organic substance components from sugar, dewatering, dredging, pulp and paper industry, and condensation of mine wastes.…”