Lakhveer Singh

A Recent Overview of Palm Oil Mill Effluent Management via Bioreactor Configurations

Worldwide, crude palm oil industries generate an overwhelming amount of palm oil mill effluent (POME). Since the past few decades, environmental issues associated with POME disposal have challenged the palm oil-producing nations which led them to reevaluate and develop their waste management strategies by using advanced biotreatment technologies. With the help of these technological advances, POME has emerged as a valuable biomass resource with great potential to produce sustainable renewable resources like biogas. This review entails various POME treatment methods in vogue and offers an insight into their improved applicability potential and pollution mitigation strategies by using proposed improved configurations like ponding system, open digesting tanks, anaerobic digestion based-bioreactors, aerobic anaerobic hybrid bioreactors, and membrane bioreactors. This review paper also gives an overview about the recent advancements in POME treatment bioreactor configurations and emphasizing their scope in large-scale applications on an industrial level. This review also critically analyzes their performance level to achieve the standard POME discharge limit by efficiently removing high COD (chemical oxygen demand), BOD (biological oxygen demand), and TSS (total suspended solid).

Novel mesoporous MnCo 2 O 4 nanorods as oxygen reduction catalyst at neutral pH in microbial fuel cells

The aim of this work was to evaluate the comparative performance of hybrid metal oxide nanorods i.e. MnCo2O4 nanorods (MCON) and single metal oxide nanorods i.e. Co3O4 nanorods (CON) as oxygen reduction catalyst in microbial fuel cells (MFC). Compared to the single metal oxide, the hybrid MCON exhibited a higher BET surface area and provided additional positively charged ions, i.e., Co2+/Co3+ and Mn3+/Mn4+ on its surfaces, which increased the electro-conductivity of the cathode and improved the oxygen reduction kinetics significantly, achieved an io of 6.01u202fA/m2 that was 12.4% higher than CON. Moreover, the porous architecture of MCON facilitated the diffusion of electrolyte, reactants and electrons during the oxygen reduction, suggested by lower diffusion (Rd), activation (Ract) and ohmic resistance (Rohm) values. This enhanced oxygen reduction by MCON boosted the power generation in MFC, achieving a maximum power density of 587u202fmW/m2 that was ∼29% higher than CON.