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Desalination of hypersaline brine is known as one of the methods to cope with the rising global concern on brine disposal in high-salinity water treatment. However, the main problem of hypersaline brine desalination is the high energy usage resulting from the high operating pressure. In this work, we carried out a parametric analysis on a spiral wound membrane (SWM) module to predict the performance of hypersaline brine desalination, in terms of mass transfer and specific energy consumption (SEC). Our analysis shows that at a low inlet pressure of 65 bar, a significantly higher SEC is observed for high feed concentration of brine water compared with seawater (i.e., 0.08 vs. 0.035) due to the very low process recovery ratio (i.e., 1%). Hence, an inlet pressure of at least 75 bar is recommended to minimise energy consumption. A higher feed velocity is also preferred due to its larger productivity when compared with a slightly higher energy requirement. This study found that the SEC reduction is greatly affected by the pressure recovery and the pump efficiencies for brine desalination using SWM, and employing them with high efficiencies (ηR ≥ 95% and ηpump ≥ 50%) can reduce SEC by at least 33% while showing a comparable SEC with SWRO desalination (

Recombinant human erythropoietin (rhEPO) has been saving millions of lives worldwide as a potent and safe treatment for the lack of erythrocyte, which is caused by chronic kidney disease (CKD) and other issues. Several biosimilars of rhEPO have been approved since the expiry of the relevant patents to provide cost-effective options but the price of rhEPO is still high for the affordability of global community. Therefore, development of biosimilar of rhEPO at a lower price is highly necessary. Here we report the development and characterization of a biosimilar of rhEPO with high-yield satisfying regulatory requirements. The hEPO-expressing cDNA was stably expressed in CHO cells with successive transfection. The master cell bank (MCB) and working cell bank (WCB) were established from the best selected clone and characterized for 50 passages. The rhEPO was expressed from the WCB in single-use suspension culture system with a high-titer (1.24±0.16 g/L). To the best of our knowledge this is the highest reported rhEPO titer to date. The rhEPO was purified using a series of validated chromatography unit processes including virus inactivation and filtration. The purified EPO was formulated in serum-free buffer, sterile filtered, and analyzed as the biosimilar of reference product Eprex®. Physicochemical analysis strongly suggested similarities between the developed rhEPO (GBPD002) and the reference. Thein vitroandin vivofunctional assays confirmed the similar biofunctionality of the GBPD002 and Eprex®. GBPD002 could provide a less-expensive solution to the needful communities as an effective and safe biosimilar where rhEPO treatment is necessary.

In this present work, Carbon@exfoliated g–C3N4 was fabricated through a facile hydrothermal approach. Detailed characterizations were performed to examine the crystal structure, specific surface area, elementary composition, morphology, optical properties and also photoreforming activities. The deposition of carbon onto the exfoliated g–C3N4 structure shows enhanced surface area of 43.9 m2/g relative to bulk g–C3N4 (34 m2/g). Additionally, UV–vis DRS evidenced the enhancement of light absorption in the visible region. The adequacy of the fitted quadratic model was validated by values such as R–squared, F–value and p–value of 0.9922, 136.45 and

Co-cultures of different microorganisms are considered promising inocula for treating palm oil mill effluents (POME) and producing value-added bio-products (e.g., biofuels and fatty acid-derived materials). However, the efficiency of yeast-bacteria co-culture for microbial lipid production through bioremediation of wastewater remains a bottleneck. In this study, the performance of a co-culture for lipid accumulation through POME bioremediation was investigated using a yeast (Lipomyces starkeyi) and a bacterium (Bacillus cereus). A maximum biomass of 8.89 ± 0.33 g/L and lipid production of 2.27 ± 0.10 g/L were achieved by the co-culture inoculum, which were substantially higher than those of the monocultures. Besides, the co-culture inoculum attained a maximum chemical oxygen demand (COD) removal of 83.66 ± 1.9%, while the individual cultures of B. cereus and L. starkeyi obtained 74.35 ± 1.7% and 69.01 ± 2.3%, respectively. The bioremediation efficiency was confirmed by the seed germination index (GI) of Vigna radiata (Mung bean). It was observed that the co-culture inoculum had a higher GI compared to the untreated POME and even the monoculture-treated POME. We argue that the symbiotic association of a yeast-bacteria co-culture in POME could be an attractive approach for achieving maximum biomass as well as lipid production and simultaneous bioremediation of POME.

Graphitic carbon nitride (g-C3N4) has been well-known as an appealing semiconducting material for photocatalytic hydrogen production despite its restricted active sites and poor electronic properties. In this work, exfoliated g-C3N4 nanosheets were synthesised by chemical treatment of the bulk graphitic carbon nitride (gCN) and the nanosheets were further doped with CdO. The photocatalysts produced were extensively characterized by diverse analysis including XRD, BET, XPS, TEM, FESEM, UV-Vis spectroscopy and PL analysis. The BET surface area of CdO/exfoliated g-C3N4, 40.1 m2 g−1 was doubled in comparison to the exfoliated g-C3N4. Numerous electrochemical analyses such as Mott-Schottky, linear weep voltammetry and chronoamperometry were also performed in a standard photoelectrochemical system with three-electrode cell. The hydrothermally synthesised CdO/exfoliated g-C3N4 resulted higher amount of hydrogen evolution (145 μmol/g) for the photoreforming of aqueous formaldehyde than the CdO (20 μmol/g), bulk gCN (58 μmol/g) and exfoliated g-C3N4 (87 μmol/g). The excellent hydrogen production rate using CdO/exfoliated g-C3N4 nanocomposite could be ascribed by higher number of active sites as well as shorter path of the charge carries to the reaction surface. The anticipated Z-Scheme mechanism has demonstrated a synergistic impact between the CdO and exfoliated g-C3N4 where the organic compounds acting as hole scavenger as well as contribute protons, H+ for the effective hydrogen production. Thus, it is clearly confirmed that the newly formulated CdO/exfoliated g-C3N4 has an outstanding potentiality for environmental remediation and conversion sectors.

The present study was aimed to convert CO2 into methanol which not only addresses the potential solution for controlling the CO2 concentration level in the atmosphere but also offers an alternative approach for the production of renewable energy source. In this perspective, a hybrid photocatalyst, PANI@CuFe2O4 was synthesized, characterized and used as a photocathode for photoelectrocatalytic (PEC) reduction of CO2 to methanol in aqueous medium at an applied potential of −0.4 V vs NHE under visible light irradiation. The combination of PANI with CuFe2O4 greatly increased the PEC CO2 reduction to methanol owing to enhance the CO2 chemisorption capacity by the photocathode surface and at the same time facilitated the separation of photogenerated electron-hole (e−/h+) pairs. The incident photon to current efficiency (IPCE) and quantum efficiency (QE) for methanol formation in PEC CO2 reduction could be achieved as 7.1 and 24.0% respectively. The rate of formation of methanol in PEC CO2 reduction was found as 49.3 μmol g−1h−1 with 73% Faradaic efficiency. Compared to photocatalytic reaction, the PEC results demonstrated that the applied potential could effectively separate the photogenerated e−/h+ pairs and therefore, enhanced the PEC CO2 reduction activity of the hybrid photocatalyst.

Current research involved fabrication of cadmium oxide-graphitic carbon nitride (CdO/g-C3N4) nanocomposite and evaluation of their photocatalytic properties by physical and electrochemical analysis techniques. The X-ray diffraction (XRD) test demonstrated that the nanocomposite consists of graphite and monteponite phases. UV–Vis absorption and photoluminescence (PL) analysis clearly pointed out both the band gap reduction and inhibition in recombination rate of charge carriers. Based on the photoelectrochemical (PEC) analysis, linear sweep voltammetry (LSV) data demonstrated that CdO/g-C3N4 nanocomposite shows higher anodic current (0.57 mA/cm2) under light emission as compared to dark environment (0.02 mA/cm2). This study was also deliberated with proposed mechanism on photoreforming of wastewater reaction scheme.

As the global interest heading towards net zero emission by 2050, clean hydrogen production technologies becomes limelight among the research community. Besides, the generation of large quantity of industrial wastewaters creates huge dilemma and needs special attention. In this work, synthetic wastewater using formaldehyde (FA) as a model organic pollutant was utilized to produce hydrogen. The photocatalyst, CuO@exfoliated g-C

A series of fluorescence-containing indazole-fused ring systems were made with the support of g-C3N4/CuO as a catalyst via non-conventional (microwave) method. We have synthesized g-C3N4/CuO nanocomposites by mechanochemical process; further, its morphology and composition were studied using various instrumental techniques like Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). Also, we have synthesized pyrimido[1, 2-b] indazole-4-yl methanol motifs without any solvent in single-step methodology utilizing microwave irradiation. The pyrimido[1, 2-b] indazole-4-yl methanol motifs were optimized using response surface methodology (RSM). This preparation was effortlessly accessible, and the overview of the substrates was authorized. The pyrimidoindazole core structures exhibit the most remarkable photo physical properties. Most of the pyrimidoindazole scaffold appears in solvatochromism and excited with blue–green fluorescence shift while using ethyl acetate as solvent. This result indicates that synthesized pyrimidoindazole core motifs have prodigious potential as fluorophores which will help us to study several applications. Graphic abstract

The hybrid graphitic carbon nitride-cadmium oxide (g-C3N4/CdO) nanocomposite was fabricated using chemical precipitation and self-assembly method. The photocatalysts were characterised by XRD, XPS, FTIR, BET, TEM, FESEM, UV-Vis and PL spectroscopy. Based on the optical study, visible light harvesting was improved and the band gap of bulk g-C3N4 to hybrid g-C3N4/CdO nanocomposite was greatly reduced from 2.72 eV to 2.35 eV, signifying a better charge carrier mobility. The photocatalytic activity were further assessed by conducting rhodamine B (RhB) photodegradation reaction using visible light. An excellent dye removal efficiency of 96% was achieved when 1.5 g/L of hybrid g-C3N4/CdO nanocomposite was used with an initial concentration of 10 ppm for 120 min whereas only 66% of RhB was removed by bulk g-C3N4 within the same operating conditions. Besides, reusability tests were carried out and evidenced that hybrid g-C3N4/CdO nanocomposite can be recycled up to four times by retaining the degradation efficiency. The scavenging studies confirmed that the RhB photodegradation using hybrid g-C3N4/CdO nanocomposite was controlled by valance band h+ and O2− oxidation reactions. Conclusively, the inclusion of CdO onto g-C3N4 resulted in remarkable photocatalytic activity for dye degradation applications.

Plastic injection moulding is widely used for manufacturing due to variety of plastic product. In this study, plastic part defects such as air bubble and gas mark defect are commonly occurs in thermoplastic part, specifically acrylonitrile butadiene styrene (ABS). In order to optimize the process parameters of injection moulding, design of experiment (DOE) with Response Surface Methodology (RSM) model was used. Process parameters such as melt temperature, mould temperature and injection pressure were selected for the DOE development. The experiments were conducted with melt temperature range from 200 °C to 240 °C, mould temperature from 60 °C to 80 °C and injection pressure from 90 to 99%. The result indicates that, all the selected parameters were significantly influence the rejection rate of the automotive ABS part. The optimum melt temperature, mould temperature and injection pressure were 220 °C, 70 °C and 98% respectively, in obtaining minimum rejection rate.

In this work, glycerol valorization into tartronic acid – one of the most valuable derivatives of glycerol – was reported over platinum supported on multi-walled carbon nanotubes (Pt/CNT) electroca...

Colloidal Mg(OH)2/MgO nanoparticles were successfully produced in glycerol medium in the presence of hydrazine and subsequently was characterized by XRD. The as-prepared colloidal suspension in glycerol was used for the glycerolysis reaction with palm oil succeeded by polyesterification reaction with phthalic anhydride to prepare the palm oil-based alkyd resin nanocomposite where the Mg(OH)2/MgO nanoparticles catalysed the reactions. The well-dispersion of Mg(OH)2/MgO nanoparticles in the reaction mixture formed a stable suspension which effectively elevated the rate of reaction of both alcoholysis and polyesterification as compared to conventional NaOH catalysed reactions. The optimum reaction condition of the catalysts was observed at 0.04 wt% of Mg(OH)2/MgO. Alkyd resin nanocomposite formation was verified through FTIR, 13C NMR and 1H NMR. The presence of the Mg(OH)2/MgO nanoparticles in the resin matrix significantly improved the antimicrobial activity as evidenced by Kirby–Bauer Method. Thereby, the formulation of Mg(OH)2/MgO nanoparticles in glycerol medium was proved to be an effective route as compared to traditional NaOH homogeneous base catalyzed system.

In the present paper, hetero-structured CdS–CuFe2O4 nanocomposite was synthesized by a facial method to convert CO2 to methanol in the photoelectrochemical (PEC) system. The synthesized catalysts were characterised by XRD, Raman spectroscopy, TEM, FESEM, EDX, XPS, UV–vis and PL spectroscopy. The CdS–CuFe2O4 photocatalyst showed ~6 times higher photocurrent compared to the CuFe2O4 at −0.35 V vs. NHE of bias potential under CO2 environment as revealed by chronoamperometry results. Incident photon to current efficiency (IPCE) for CuFe2O4 and CdS–CuFe2O4 at 470 nm were found as 7.28 and 12.09%, respectively which clearly indicates the proficiency of CdS–CuFe2O4 heterojunction to absorb the visible light resulting in e−/h+ generation and the charge transfer during PEC CO2 reduction. Products in aqueous and gas phases were analysed which confirmed the selective production of methanol with trace amounts of H2 and CO. The CdS–CuFe2O4 catalyst demonstrated 72% and 16.9% of Faradaic and quantum efficiencies, respectively in terms of methanol production where a methanol yield of 23.80 μmole/Lcm2 was achieved in CO2 saturated aqueous solution of NaHCO3 (0.1 M). Detailed investigation revealed that the conduction band (CB) of the CdS in the heterojunction catalyst could act as a CO2 reduction site by trapping photogenerated electrons from the highly photosensitive CuFe2O4 while the water oxidation could take place at the valance band (VB) of CuFe2O4.

Nanocomposites synthesized by alternative approaches like biosynthetic methods are safer than those prepared by traditional chemical techniques. Further, this approach is both economically and environmentally feasible. In this study, we report an eco-friendly methodology for preparing cerium dioxide/molybdenum disulphide (CeO2/MoS2) nanocomposites. Moringa oleifera peel was used as the reducing/stabilizing agent for synthesizing CeO2 nanoparticles. The prepared nanocomposite were characterized using FT-IR analysis, SEM and EDAX analysis, TEM and SAED pattern analysis, X-Ray Diffraction Pattern, Zeta Potential, UV-Visible Diffuse Reflectance Spectra, X-Ray Photon Spectroscopy and Photoluminescence spectra. Particle size and morphology were characterized by TEM and SEM. The photocatalytic pursuit of CeO2/MoS2 was explored by the degradation of methyl violet (MV) under visible light irradiation. Our methodology proved to be 96.25% effective in the degradation of MV. Further, we used this Response Surface Methodology for enhancing the process factors like volume of photocatalyst, time for degradation and concentration of MV.

The present study demonstrates the effect of light irradiation on the esterification of oleic acid catalyzed by immobilized Pseudomonas cepacia lipase. The reaction rates of all the experiments under light irradiation were found to be higher than dark conditions. The kinetics of reactions supported the Ping‐Pong Bi‐Bi mechanism with dead end inhibition by both the alcohol and acid substrates. Moreover, circular dichroism (CD) spectroscopy was used to analyze the effect of light on lipase enzyme. The CD spectroscopic studies confirmed that the conformational changes in the secondary structure of the lipase enzyme increased the reaction rate of light‐illuminated experiments, which might have opened up the active sites of enzymes and thus, resulted in higher reaction rates compared to dark reactions. These results have successfully demonstrated that the light illumination positively influenced the rate of P. cepacia enzyme‐catalyzed esterification reactions.

The wastewater burden and increased energy demands have spurred interest in finding possible solutions that could concomitantly address both issues. Microbial lipid production, together with the bioremediation of wastewater, could be a promising solution to address both problems. In this context, the present study was designed to evaluate the potential of Bacillus cereus (B. cereus) for accumulating microbial lipids through the bioremediation of palm oil mill effluent (POME) in batch mode fermentation. Different dilutions of POME media (25%, 50%, 75%, and 100%) were used to determine the optimum POME concentration for enabling the maximum yield of biomass and maximum lipid production. The 50% (v/v) POME was found to have potential for the highest biomass growth (8.09 g/L) and lipid accumulation (1.46 g/L), with a lipid content of 18.04% (dry weight basis). B. cereus accumulated a higher biomass and lipid content than other bacterial strains, such as Rhodococcus opacus and Pseudomonas aeruginosa, under similar conditions. On the other hand, the degree of bioremediation was assessed by evaluating several wastewater parameters and determining the seed germination index (GI) of Vigna radiata. POME treated with B. cereus displayed higher GI values than the untreated samples due to the significant remediation of detrimental organics present in the POME. This finding was further confirmed by the substantial reduction in pollution load, particularly in chemical oxygen demand (COD) and biochemical oxygen demand (BOD) for 50% POME, thus demonstrating removal efficiencies of 79.35% and 72.65%, respectively. Therefore, the results of this study suggest that B. cereus cultivation in POME could be a promising technique for attaining higher biomass growth and lipid production in conjunction with the bioremediation of POME. The approach of achieving dual objectives that is utilized in the present study provides a novel strategy for palm oil millers.

In the present study, the applicability of electroporation (EP) has been investigated as a pretreatment method for enriching hydrogen producers and eliminating hydrogen consumers in anaerobic sludge (AS). Citrus wastewater was used as a feed source for biohydrogen production. Different treatment intensities (TI) of EP for 0.5 min (TI = 30 kWh/m3), 1 min (TI = 60 kWh/m3), and 2 min (TI = 120 kWh/m3) were employed to observe the effects of EP on the microbial community of AS. Furthermore, sonication with a probe, sonication in a bath, and heat-shock pretreatments were also conducted to compare the hydrogen yield with EP. The cell inactivation was evaluated and visualized using colony-forming units (CFU) and field emission scanning electron microscopy (FESEM), respectively. Among the different TIs, the TI of 60 kWh/m3 achieved higher methanogen inactivation with maximum hydrogen (896 mL) production compared to other EP pretreatments after 180 h of dark fermentation. In comparison with other pretreatments, the highest hydrogen production of 896 mL was achieved with EP treatment, followed by sonication with a probe (678 mL) and sonication in a bath (563 mL). The heat-shock pretreatment exhibited the lowest ultimate hydrogen production of 545 mL among the four different methods applied in this study. The outcome of this study suggests that EP is a promising technique for pretreating mixed cultures for the enhanced production of biohydrogen.

Photoelectrocatalytic reduction of CO2 into valuable products can provide energy in a sustainable way with leveling off of the concentration of CO2 in our environment. In this study, graphene oxide (GO) incorporated with copper ferrite (CuFe2O4) has been employed to enhance photoelectrocatalytic CO2 reduction under visible light. The TEM and XPS characterization indicated a strong interaction between the CuFe2O4 and GO in the hybrid catalyst. The GO incorporation reduced the e–/h+ recombination in the hybrid catalyst by trapping the photoexcited electrons from CuFe2O4 leading to high methanol yield of 28.8 μmol L–1 cm–2 at 20.5% quantum efficiency. The incident photon current efficiency (IPCE) and Faradaic efficiency for methanol formation were observed as 8.02% and 87%, respectively. The results showed that the photoelectrocatalytic activity for CO2 reduction can be improved by incorporating GO with CuFe2O4, and it provides a universal platform to fabricate GO–CuFe2O4 based hybrid photocatalyst with prom...

In this work, palm kernel meal (PKM) and palm shell (PS) were studied as a filler for wood adhesive formulations and their efficiency was compared with existing industrial flour (IF). Melamine urea formaldehyde (MUF) was used as resin for formulating the wood adhesives. The effects of the natural fillers (PKM and PS) on shear strength and formaldehyde emission of plywood were analyzed. The optimum hot press temperature and time were found to be 125 °C and 150 s, respectively. Both PKM and IF influenced the shear strength and formaldehyde emission characteristics, with the optimum concentration of filler being within the range of 13% to 18%. The physico-chemical interaction between the wood, resin and filler was investigated using Fourier transform infrared spectroscopy (FTIR) and the interactions among C˭O groups on PKM and N‒H, O‒H groups on wood and MUF were identified. Apart from the bonding strength, the mechanical interlocking between adhesive and wood was found to be very important for adhesive performance which was dependent on the viscosity of the adhesive which in turn was controlled by the filler concentration. The wood –adhesive interface was examined using light microscopy (LM).

Effective vaccine against SARS-CoV-2 is the utmost importance in the current world. More than 1 million deaths are accounted for relevant pandemic disease COVID-19. Recent data showed that D614G genotype of the virus is highly infectious and responsible for almost all infection for 2nd wave. Despite of multiple vaccine development initiatives, there are currently no report that has addressed this critical variant D614G as vaccine candidate. Here we report the development of an mRNA-LNP vaccine considering the D614G variant and characterization of the vaccine in preclinical trial. The surface plasmon resonance (SPR) data with spike protein as probe and competitive neutralization with RBD and S2 domain revealed that immunization generated specific antibody pools against the whole extracellular domain (RBD and S2) of the spike protein. The anti-sera and purified IgGs from immunized mice on day 7 and 14 neutralized SARS-CoV-2 pseudovirus in ACE2-expressing HEK293 cells in a dose dependent manner. Importantly, immunization protected mice lungs from pseudovirus entry and cytopathy. The immunologic responses have been implicated by a balanced and stable population of CD4+ cells with a Th1 bias. The IgG2a to IgG1 and (IgG2a+IgG2b) to (IgG1+IgG3) ratios were found 1±0.2 and 1.24±0.1, respectively. These values are comparatively higher than relevant values for other published SARS-CoV-2 vaccine in development,1, 2 and suggesting higher viral clearance capacity for our vaccine. The data suggested great promise for immediate translation of the technology to the clinic.

In the present paper, the potentiality of integrating microbial fuel cells (MFCs) with a photocatalytic reactor to maximize the wastewater treatment efficiency with concurrent power generation was explored. Dimethyl phthalate (DMP) and acetic acid (AA) were the employed substrate and the co-substrate, respectively, using Pseudomonas aeruginosa as a biocatalyst. MFCs operated by single substrate showed the maximum power generation of 0.75–3.84 W m−3 whereas an addition of AA as the co-substrate yielded 3–12 fold higher power generation. Pseudomonas aeruginosa produced phenazine-1-carboxylic acid in DMP-fed MFC as the metabolite whereas AA along with DMP yielded pyocyanin which reduced the charge transfer resistance. Chemical oxygen demand (COD) removal efficiency in the MFCs was circa 62% after 11 days of operation. Thereafter, it further increased albeit with a drastic reduction in power generation. Subsequently, the MFC anolyte was treated in a photocatalytic reactor under visible light irradiation and catalyzed by CuO-gC3N4. The performance of photocatalytic reactor was evaluated, with COD and total organic carbon (TOC) removal efficiency of 88% and 86% after 200 min of light irradiation. The present work suggests that the MFC can be integrated with photocatalysis as a sustainable wastewater treatment method with concurrent power generation.

Microalgal biofuels are considered as one of the most promising substitutes to the nonrenewable fossil fuels. However, the efficient recovery of microalgal lipids is emergent for the overall process economics and sustainability. The conventional lipid extraction technique entails direct use of organic solvents to liberate the intracellular lipids, thus making the extraction process more time-consuming and less eco-friendly. Furthermore, the efficiency of extraction process is affected by several problems, such as the rigid structure and composition of microalgal cell walls, the water content of biomass, the limited accessibility of lipids, the reduced mass transfer, and the formation of stable emulsions. Various modifications (e.g., use of green solvents, direct transesterification, pretreatment for disrupting microalgal cells, etc.) to conventional lipid extraction have been proposed to mitigate the problems associated with lipid extraction. Among them, the pretreatment approach (i.e., mechanical, chemical, biological cell disruption) in combination with solvent-based extraction would be a promising approach to address the problems during lipid extraction. Therefore, intensive research, review, and analysis are required to understand the challenges in lipid extraction and to develop a useful extraction process in terms of biomass status (dry/wet), solvent use, lipid yield, extraction time, and scalability. In this chapter, we have reviewed the composition and possible applications of microalgal lipids with the main challenges in their extraction process. Furthermore, the advantages and limitations of several pretreatment methods for cell disruption have been comprehensively discussed.

The depletion of nonrenewable energy sources drives the exploration for renewable energy sources as an alternation route of energy generation. Hence, in the past decade, research efforts have been employed to explore potential renewable energy sources utilizing waste biomass. Anaerobic digestion (AD) is considered as an efficient technique to treat different kinds of wastes such as agricultural, industrial, and food wastes to produce renewable energy. Until now, two predominant fermentation processes, namely submerge or liquid-state anaerobic fermentation (LSAF) and dry or solid-state anaerobic fermentation (SSAF) have been implemented to extract energy from waste biomass. Nowadays, SSAF is claimed to be more advantageous than LSAF for a number of reasons including its comparatively smaller reactor volume, lower energy requirements for heating, minimal material handling, and lower total parasitic energy loss. Due to its low moisture content, the digestate of SSAF can be used as fertilizer or pelletized fuel, which is much easier to handle than the effluent from LSAF. However, for enhancing the performance of dry AD processes, a suitable reactor needs to be designed so that the maximum amount of substrate could be fermented, to make the technology more economically viable. Therefore this chapter is aimed at discussing the different kinds of bioreactors along with their potential benefits, challenges, and limitations, which have been explored recently for biogas production through dry fermentation.

This paper presents the performance of air-cathode microbial fuel cell (AC-MFC) treating the petrochemical wastewater (PCW) from acrylic acid plant. The wastewater which is typically incinerated and possesses very high chemical oxygen demand (COD) due to presence of acrylic acid along with other organic acids. The goal of the present study is to evaluate the viability of treating the wastewater using yeast (Saccharomyces cerevisiae) as biocatalyst in AC-MFC for simultaneous treatment of wastewater and electricity generation. This study demonstrates that Saccharomyces cerevisiae could function as a good biocatalyst producing high power density of 0.24 W/m3 using PCW with an initial COD of 26,000 mg/L. The COD removal efficiency and the columbic efficiency (CE) were found as 38% and 23.6% respectively. The electron transfer process across the electrode/biofilm/solution interface was analyzed by electrochemical impedance spectroscopy (EIS). The present work demonstrates the potential of MFC for the treatment of acrylic acid plant PCW using Saccharomyces cerevisiae as biocatalyst.

The interspecies interactions in microbial communities are very complex, rendering identification of synergistic or antagonistic relationships very difficult; however, understanding the mutualistic relationship between the microbes is exigent to gain deeper insight into their performance in wastewater fed microbial fuel cells (MFCs). In the present study, we aimed to explore the ecological networks between the microorganisms in a defined coculture system comprising with Pseudomonas aeruginosa (P. aeruginosa) and Klebsiella variicola (K. variicola). The coculture showed around 3 times higher current density in MFCs compared with either of these two bacteria alone. Metabolite analysis demonstrated that the fermentative metabolite (1,3-propanediol) produced by K. variicola stimulated the P. aeruginosa to produce a higher amount of pyocyanin through synergistic interactions, leading to the enhancement in the performance of coculture MFCs fed with palm oil mill effluent (POME). This study proves that the metab...

Although exogenous mediators can distinctly enhance the performance of yeast driven microbial fuel cell (MFC), the possibility of mediator’s toxicity, environmental risk, and cost are the main challenges facing toward its application in MFCs. Therefore, the use of naturally produced electron shuttles for unmediated yeast would be of great interest since it can solve most of the above-mentioned problems. The present study is to investigate the possibility of the use of electron shuttle producing bacteria Klebsiella pneumonia (K. pneumonia) to boost up the performance of yeast Lipomyces starkeyi (L. starkeyi) driven MFC. The MFCs inoculated with L. starkeyi and K. pneumoniae coculture achieved a maximum power density of 12.87 W/m3 which is about 3 and 6 times higher than that of MFC solely inoculated with pure yeast and bacteria, respectively, demonstrating that the yeast cells have successfully utilized the reduced electron shuttles excreted by the bacteria. The occurrence of the mutualistic interactions w...

Palm oil based alkyd resin was prepared by alcoholysis–polyesterification reaction over hetero-homo catalytic system comprised of CuO nanoparticle and NaOH. In this work, CuO nano-sol was synthesized in glycerol at ambient condition via a chemical reduction method and successively used in alkyd resin preparation. The formation of CuO nanoparticle was monitored by X-ray absorption near edge structure spectroscopy (XANES) where a ‘red colour sol’ was detected. During the alkyd resin preparation, the catalytic behaviour of CuO nanoparticle was recorded by using titration method. The formation of the alkyd was confirmed by FTIR. The antibacterial behaviour of the additive was verified by Kirby–Bauer method and found that alkyd with CuO nanoparticle presented better antibacterial performance.

Biohydrogen production from different types of waste biomass using mixed culture inoculum has been an active research area in recent years. Several emerging techniques has been studied targeting to achieve higher efficiency and competitive hydrogen production through the dark fermentation. However, the production of biohydrogen from complex waste biomass meets the setback of lower final product yield due to the low substrate degradation rate. Besides, hydrogen consuming microbes in the mixed culture impede the rate of biohydrogen production. Thus, the waste biomass substrate and microbial inoculum are highly required to pretreat for enhancing system performance. With the aim to gain deeper insight into waste biomass and inoculum pretreatment techniques, this review compiles recently practiced pretreatment techniques with their limitations. The major challenges of these methods and few strategies to overcome these limitations with future directions are discussed in this review. Moreover, the efficiency of a potential nonconventional pretreatment technique such as electroporation (EP) over traditional techniques to degrade the complex waste biomass and reduce the load of hydrogen consuming microbes in the mixed culture consortium was reviewed. This review argued to provide a deeper insight to develop an efficient pretreatment technique by combining traditional techniques and EP for enhancing mixed culture driven biomass-based hydrogen production.