Electricity Generation From Dewatered Sludge Using Membrane-Less Microbial Fuel Cell

The membrane-less microbial fuel cell (ML-MFC) is an innovative renewable energy technology that becomes the alternative energy to overcome the global energy crisis. The ML-MFC operated electrochemically incorporate electrogenic bacteria (EB) acted as a biocatalyst in order to produce electricity. Dewatered sludge from three different wastewater treatment plant (A – IWK Kerian, B – IWK Butterworth and C – IWK Juru) were used as substrate in the ML-MFC. From the preliminary test sludge A showed a better performance compared to the others in term of nutrient composition, COD value and power generation. Then performance of the ML-MFC using sludge A was evaluated using one-factor-at-a-time (OFAT) method followed by response surface methodology (RSM) via Central Composite Design using a quadratic model. In the preliminary OFAT study, the highest voltage generation (852.7 mV) and COD removal (149.2 mg/L) were obtained when the pH 6.0, electrode distance (ED) 3 cm, moisture content (MC) 30 % (v/w), and temperature 35 °C. After incubation of the ML-MFC using optimum conditions suggested by the RSM (ED 3 cm, MC 32 % v/w, temperature 38 °C) the voltage (927.7 mV) and COD removal (170.8 mg/L) were successfully increased about 8.79 % and 14.47 %, respectively. This showed that optimization using RSM gave better results than the OFAT method and the maximum power density (41.31 mW/m2) was recorded. The scanning electron microscope (SEM) observation revealed the EB biofilm formation at the anode surface. The phylogenetic analysis of EB proved the presence of Pseudomonas and Bacillus subtilis species in the biofilm which actively boosted the electron transfer. The study also showed unstructured kinetic growth model, Logistic, describing well the growth behaviour of EB in the ML-MFC with high R2 value (0.991) and low RMSE (0.189). While the Leudeking-Piret like model for COD removal also performed well with R2 values recorded was 0.971 and had low RMSE value which was 0.203. The experimental data show that the Logistic and Leudeking-Piret-like model could best describe the growth of EB and COD removal in the ML-MFC. The parametric uncertainty analysis on COD removal was then assessed using the Monte Carlo simulation (stochastic variable) to determine probability distributions due to fluctuation and variation of kinetic model parameters. Result showed that based on 100,000 samples tested, the substrate removal (S) was ranged from 179.23 – 191.13 mg/L. Sensitivity analysis was also done to evaluate the impact of each kinetic parameter on the ML-MFC performance. It was found that ML-MFC performance highly depends on growth of EB present in the ML-MFC

Biosorption study of methylene blue (MB) and brilliant red remazol (BRR) by coconut dregs

Water pollution has become a major issue in many countries, including Malaysia. Malaysia is one of the countries that suffers from this detrimental influence on water resource sustainability. Adsorption has been discovered to be a cost-effective and efficient method of removing contaminants such as pigments, dyes, and metal impurities. Many biomass-based adsorbent materials have been successfully used for the removal of dyes from aqueous solutions. In this study, the potential use of coconut dregs as the new biosorbent for the removal of Methylene Blue (MB) (basic dye) and Brilliant Red Remazol (BRR) (acidic dye) was investigated. The effects of adsorption time, adsorbent dosage, pH, and initial dye concentration on coconut dregs adsorption for MB and BRR dye were investigated using 2-Level Factorial Design of Design-Expert 7.1.5. The results indicated that the amount of dye adsorbed on the coconut dregs increased with increasing dye concentration, adsorbent dosage, and adsorption time. However, both MB and BRR dyes favor different pH for the adsorption process. The adsorption capacity of MB dye increased with increasing pH, while the adsorption capacity of BRR dye increased with decreasing pH. Removal of MB was optimum at pH 11, contact time of 240 min, a dosage of 0.25 g adsorbent, and an initial dye concentration of 50 mg/L. Meanwhile, for BRR dye, the optimum condition was pH 2, contact time of 180 min, the dosage of 0.25 g adsorbent, and an initial dye concentration of 50 mg/L. The equilibrium data for both dyes fitted very well with the Langmuir Isotherm equation giving a maximum monolayer adsorption capacity as high as 5.7208 mg/g and 3.7636 mg/g for Methylene Blue Dye and Brilliant Red Remazol dye, respectively. This study shows that coconut dregs can be one of the potential and low-cost biosorbents for the treatment of industrial dyes soon

Bibliometric analysis on biobutanol production research trends from 2010-2022 using scopus database

The global demand for biofuels as an alternative energy source is on the rise due to the anticipated decline in fossil fuel (gasoline). Biobutanol, among various biofuels, has garnered significant attention for its advanced features and suitability as an alternative to fossil fuels. Recognizing the importance of understanding research issues and fostering collaborative networks, this bibliometric analysis focuses on synthesizing research trends in biobutanol production over the past 12 years. Examining 357 Scopus-indexed documents, the study shows that over 80% of relevant articles were published after 2010, indicating the recent emergence of literature in this field. Citation analysis identifies publishing trends dating back to 2010, highlighting leading scholars. In 2016, 47 publications in Chemical Engineering were attributed to the field, with Professor Sahaid authoring 12 publications, primarily affiliated with UKM. Chemical Engineering comprised the predominant subject area, with articles constituting 75.07% of total publications. Bioresource Technology was the primary source title, and the keyword Biobutanol was frequently associated with the research (92.16%). UKM led in institutional contributions with 12 publications, while India had the highest total publications at 17.65%, and Malaysia contributed 6.44%. The majority of publications (88.24%) originated from journal publications, and English was the predominant language, accounting for 96.64% of the publications. This paper underscores the recent surge in biobutanol research and the importance of collaborative efforts for further advancements

Characterization and kinetic studies of poly(Vinylidene fluoride-co-hexafluoropropylene) polymer inclusion membrane for the malachite green extraction

Textile industry effluent contains a high amount of toxic colorants. These dyes are car-cinogenic and threats to the environment and living beings. In this study, poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) was used as the based polymer for PIMs with bis-(2-ethylhexyl) phosphate (B2EHP) and dioctyl phthalate (DOP) as the carrier and plasticizer. The fabricated PIMs were employed to extract the cation dye (Malachite Green; MG) from the feeding phase. PIMs were also characterized by scanning electron microscopy (SEM), atomic force micro-scope (AFM), contact angle, water uptake, Fourier-transform infrared spectroscopy (FTIR) and ions exchange capacity. The performance of the PIMs was investigated under various conditions such as percentage of carrier and initial dye concentration. With permeability and flux values of 0.1188 cm/min and 1.1913 mg cm/min, PIM produced with 18% w/w PVDF-co-HFP, 21% w/w B2EHP, 1% w/w DOP and 40% w/w THF and was able to achieve more than 97% of MG extraction. The experimental data were then fitted with a pseudo-second-order (PSO) model, and the calculated R2 value was ~0.99. This shows that the data has a good fit with the PSO model. PIM is a potential alternative technology in textile industry effluent treatment; however, the right formulation is crucial for developing a highly efficient membrane

Characterisation of Calcium Carbonate Formed by Bacillus sphaericus Using Urea

Microbiologically induced calcium carbonate precipitation (MICCP) has emerged as rather promising green technology compares to conventional calcium carbonate process. Bacillus sphaericus LMG22557 is a superior MICCP-capable microorganism that can potentially utilise urea from diverse sources. This study focuses on maximising and characterising the calcium carbonate produced from fermentation of synthetic urea and waste urea from chicken manure. Morphologies of calcium carbonate attributed from fermentation of urea and precipitation by different calcium source were studied by microscopic observation, Fourier-Transform Infrared (FTIR) and X-Ray Diffraction (XRD). Precipitation from calcium chloride produced more vaterite while precipitation from calcium nitrate tetrahydrate produced pure calcite. Higher specific yield productivity (0.2502 mol/g cell/h) was achieved with 200 rpm and 40 g/L urea concentration. The growth of B. sphaericus in chicken manure solution was achievable but with very low yield of bicarbonate ions (less than 0.0008 mol/g cells/h). In brief, B. sphaericus is able to produce calcium carbonate from synthetic urea while further study is required for chicken manure to be used as substitute

Characterisation of calcium carbonate formed by Bacillus Sphaericus via fermentation of urea

Microbiologically induced calcium carbonate precipitation (MICCP) has emerged as rather promising green technology compares to conventional calcium carbonate process. Bacillus sphaericus LMG22557 is a superior MICCP-capable microorganism that can potentially utilise urea from diverse sources. This study focuses on maximising and characterising the calcium carbonate produced from fermentation of synthetic urea and waste urea from chicken manure. Morphologies of calcium carbonate attributed from fermentation of urea and precipitation by different calcium source were studied by microscopic observation, Fourier-Transform Infrared (FTIR) and X-Ray Diffraction (XRD). Precipitation from calcium chloride produced more vaterite while precipitation from calcium nitrate tetrahydrate produced pure calcite. Higher specific yield productivity (0.2502 mol/g cell/h) was achieved with 200 rpm and 40 g/L urea concentration. The growth of B. sphaericus in chicken manure solution was achievable but with very low yield of bicarbonate ions (less than 0.0008 mol/g cells/h). In brief, B. sphaericus is able to produce calcium carbonate from synthetic urea while further study is required for chicken manure to be used as substitute

Removal of Humic Acid Using 3-Methacryloxypropyl Trimethoxysilane Functionalized MWCNT Loaded TiO2/PES Hybrid Membrane

In the present work, a highly efficient mixed matrix membrane (MMM) for humic acid (HA) removal was developed. Multiwalled carbon nanotubes (MWCNTs) were functionalized in the presence of 3-methacryloxypropyl trimethoxysilane using the co-condensation method and were subsequently loaded with TiO2 (prepared via the sol–gel route). The as-prepared material was then incorporated into a PES polymer solution to prepare a fMWCNT-TiO2/PES hybrid membrane via non-solvent induced phase inversion. The microstructure of the membrane was characterized using Fourier transform infrared spectroscopy, atomic force microscopy, scanning electron microscopy, water contact angle, thickness, porosity, and pore size. The fMWCNT-TiO2/PES hybrid membrane was tested for the removal of HA and antifouling performance. The results show that the surface hydrophilicity of the membranes was greatly improved upon the addition of the fMWCNT-TiO2 particles. The results show that 92% of HA was effectively removed after 1 h of filtration. In comparison with pristine membrane, the incorporation of fMWCNT-TiO2 nanoparticles led to enhanced pure water flux (99.05 L/m2 h), permeate flux (62.01 L/m2 h), higher HA rejection (92%), and antifouling improvement (RFR: 37.40%, FRR: 86.02%). Thus, the fMWCNT-TiO2/PES hybrid membrane is considered to be a great potential membrane for the improvement of ultrafiltration membranes

Medium optimization for biobutanol production from palm kernel Cake (PKC) hydrolysate by clostridium saccharoperbutylacetonicum N1-4

The study aims to optimize the medium composition for biobutanol production using a Palm Kernel Cake (PKC) hydrolysate by Clostridium saccharoperbutylacetonicum N1-4. Various nutrient factors affecting biobutanol production were screened using the Plackett-Burman design. These factors included: NH4 NO3 , KH2 PO4 , K2 HPO4 , MgSO4 .7H2 O, MnSO4 .7H2 O, FeSO4 .7H2 O, yeast extract, cysteine, PABA, biotin, and thiamin. The results were analyzed by an analysis of variance (ANOVA), which showed that cysteine (P=0.008), NH4 NO3 (P=0.011) dan yeast extract (P=0.036) had significant effects on biobutanol production. The established model from the ANOVA analysis had a significant value of Pmodel>F = 0.0299 with an F-value of 32.82 which explains that the factors can explain in detail the variation in the data about the average and the interpretation is true with an R2 value of 0.993. The estimated maximum biobutanol production was 10.56 g/L, whereas the optimized medium produced 15.49 g/L of biobutanol. Process optimizations with optimum concentration of cysteine, NH4 NO3, and yeast extract have produced 21.33 g/L biobutanol which is a 37.7% improvement from the non-optimized medium. The findings show that PKC hydrolysate with the addition of optimal concentrations of the three types of medium namely, cysteine (0.15 g/L), NH4 NO3 (0.50 g/L), and yeast extract (1.5 g/L) during ABE fermentation, yielded a maximum biobutanol concentration of 21.33 g/L. Therefore, the results of this study provide good indications for promoting PKC hydrolysate as a new source of novel substrates with great potential in producing high biobutanol through ABE fermentation by C. saccharoperbutylacetonicum N1-4

Eliciting researchers’ behaviour as the foundation of research data management service development

Background. Research data management (RDM) has become an important activity in universities, for researchers to fulfil funding agencies’ and journal publication requirements, and to promote open science practices. Academic libraries have been identified as the locations to base RDM services. However, to develop effective RDM services, an understanding of RDM from the researchers’ perspectives is needed, including how researchers manage their research data.Published versio

The role of RhoH in TCR signalling and its involvement in diseases

As an atypical member of the Rho family small GTPases, RhoH shares less than 50% sequence similarity with other members, and its expression is commonly observed in the haematopoietic lineage. To date, RhoH function was observed in regulating T cell receptor signalling, and less is known in other haematopoietic cells. Its activation may not rely on the standard GDP/GTP cycling of small G proteins and is thought to be constitutively active because critical amino acids involved in GTP hydrolysis are absent. Alternatively, its activation can be regulated by other types of regulation, including lysosomal degradation, somatic mutation and transcriptional repressor, which also results in an altered protein expression. Aberrant protein expression of RhoH has been implicated not only in B cell malignancies but also in immune-related diseases, such as primary immunodeficiencies, systemic lupus erythematosus and psoriasis, wherein its involvement may provide the link between immune-related diseases and cancer. RhoH association with these diseases involves several other players, including its interacting partner, ZAP−70; activation regulators, Vav1 and RhoGDI and other small GTPases, such as RhoA, Rac1 and Cdc42. As such, RhoH and its associated proteins are potential attack points, especially in the treatment of cancer and immune-related diseases