Corrigendum: The presence of microplastics in commercial salts from different countries

This is the final version. Available from Springer Nature via the DOI in this recordThe article to which this is the corrigendum is in ORE at http://hdl.handle.net/10871/27394This corrects the article published in Scientific Reports Vol. 7, article 46173; published online: 06 April 2017; updated: 26 June 2017 DOI: 10.1038/srep46173

The presence of microplastics in commercial salts from different countries

This is the final version of the article. Available from Springer Nature via the DOI in this record.The corrigendum to this article is in ORE at http://hdl.handle.net/10871/34751The occurrence of microplastics (MPs) in saltwater bodies is relatively well studied, but nothing is known about their presence in most of the commercial salts that are widely consumed by humans across the globe. Here, we extracted MP-like particles larger than 149 μm from 17 salt brands originating from 8 different countries followed by the identification of their polymer composition using micro-Raman spectroscopy. Microplastics were absent in one brand while others contained between 1 to 10 MPs/Kg of salt. Out of the 72 extracted particles, 41.6% were plastic polymers, 23.6% were pigments, 5.50% were amorphous carbon, and 29.1% remained unidentified. The particle size (mean ± SD) was 515 ± 171 μm. The most common plastic polymers were polypropylene (40.0%) and polyethylene (33.3%). Fragments were the primary form of MPs (63.8%) followed by filaments (25.6%) and films (10.6%). According to our results, the low level of anthropogenic particles intake from the salts (maximum 37 particles per individual per annum) warrants negligible health impacts. However, to better understand the health risks associated with salt consumption, further development in extraction protocols are needed to isolate anthropogenic particles smaller than 149 μm

Optimization of process parameters for alkaline-catalyzed transesterification of palm oil using response surface methodology

Biodiesel (fatty acid methyl esters) was synthesized from direct transesterification of vegetable oils, where the corresponding triglycerides react with methanol in the presence of a suitable catalyst. The alkali catalysts are the most common catalyst used in biodiesel industry, because the process proves faster and the reaction conditions are moderate compared to the acid catalyst. In the present study, biodiesel production using heterogeneous alkaline-catalysed transesterification process (KOH supported on SBA 15) was proposed. The influence of reaction temperature x1 (50 – 90 oC), ratio of methanol to oil, x2 (6:1 – 14:1 mol/mol), amount of catalyst, x3 (1 – 5wt.%), and reaction time, x4 (2 – 6 h) to the reaction was studied. These four conditions were studied using design of experiment (DOE), based on four-variable central composite design (CCD) with α = 2. The process variables were optimised using the Response Surface Methodology (RSM) in obtaining the maximum yield of biodiesel. This method was also applied to determine the significance and interaction of the variables affecting the biodiesel production. The biodiesel produced in the experiment was analysed by gas chromatography, which considered five major fatty acid methyl esters. The optimal conditions of response were found to be 70 oC for reaction temperature, 11.6 wt/wt of ratio methanol to oil, 3.91wt.% of weight of catalyst and 5 h for reaction time with 93% of biodiesel yield for predicted value and 87.3% from experimental

Synthesis and Characterization of Nickel (II) Oxide/Gadolinium-Doped Ceria (NiO/GDC) Nanocomposites As a Potential Material for Anode Supported LT-SOFCs

In this study, Ni-GDC Nano-powder was synthesized via ion-exchange technique using sodium alginate as the templating material. Nanoparticles were obtained by controlling the calcination temperature. FE-SEM showed that the particle size of the grain decreased with the increase in the calcination temperature. Furthermore, pure NiO-GDC structure was obtained at the calcination temperature of 500 C with no secondary phase present which is evident through the compositional characterization performed including XRD, FTIR and TGA analysis. The usage of ion-exchange sol gel technique has shown promising results to overcome high polarization observed at low operating temperature

Grafted Copolymerized Chitosan and Its Applications as a Green Biopolymer

Chitosan is a linear polysaccharide that can be synthesized through the deacetylation of chitin, a naturally abundant biopolymer found in the exoskeleton of crustaceans. It has received a lot of attention because of important features such as biodegradability, biocompatibility and antibacterial and regenerative properties. These features render it useful as the basic building block in important applications such as adsorptive wastewater treatment, sustained drug delivery, gene therapy, and electrosensors. Grafting this polymer with different types of moieties enhances its properties in different ways, e.g., grafting polyethylene glycol (PEG) to chitosan increases its solubility, and subsequently tuning the percent content of PEG imparts thermoresponsivity to the hydrogel. In this chapter, different applications of grafted chitosan are outlined with respect to different types of moieties, cross-linking reagents, grafting techniques, and experimental parameters such as the pH and the percent concentration of polymers

Advanced Material for Pharmaceutical Removal from Wastewater

The 15 state-of-the-art review chapters contained in this book cover the recent advancements in the area of waste water, as well as the prospects about the future research and development of smart materials for the waste water applications ..

Synthesis and Characterization of Nanocrystalline NiO-GDC via sodium alginate- mediated ionic sol gel method

In this study, nanocrystalline nickel oxide gadolinium-doped ceria (NiO-GDC) powder was synthesized using an ionic sol-gel method. The effects of calcination time and temperature on the particle size and the physiochemical properties of nanocrystalline NiO-GDC are presented in this paper. Using this method, gel beads were formed by contacting sodium alginate solution as the gelling template and metal (gadolinium/cerium/Ni) nitrates as the precursor. The obtained nanocrystallites were characterized using Field Emission Scanning Electron Microscopy, powder X-ray diffraction, energy dispersive X-ray spectroscopy, thermo gravimetric analysis, nitrogen adsorption/desorption analysis, and Fourier transform infrared spectroscopy. It was observed that the increasing calcination temperature had affected both the particle size and the surface area of the NiO-GDC, whereas the increasing calcination time had only impacted the size of the particles. The smallest mesoporous nanocrystalline NiO-GDC powder (12.1225 ± 0.005 m2/g surface area), composed of cubic GDC (5.18 nm crystallite size) and cubic NiO (7.99 nm crystallite size) were synthesized at a calcination temperature of 500 °C for 2 hours. This study hopes to inspire more researches on the ionic-gelation method for synthesizing other metal nanostructures as well as other reaction parameters

Adsorption Mechanism of Microcrystalline Cellulose as Green Adsorbent for the Removal of Cationic Methylene Blue Dye

The adsorption mechanism of pure cellulose is yet to be explored. Thus, in this study, the adsorption mechanism of Microcrystalline Cellulose (MCC), a polysaccharide which is renewable, low cost and non-toxic, was studied on the adsorption of model dye Methylene blue (MB). It was found that the main adsorption mechanism of MB on MCC was due to the electrostatic attraction between the positively charged MB dye and negatively charged MCC. Thus, physical adsorption was the dominant effect, since electrostatic attraction is categorized as physical adsorption. This was verified by Dubinin-Radushkevich isotherm, whereby mean free energy adsorption value was found to be less than 8 kJ/mol. The values of Gibbs free energy for thermodynamics studies were found to be within the range of -20 kJ/mol and 0 kJ/mol, which also indicated physical adsorption. It was due to the electrostatic attraction as adsorption mechanism of this adsorption process which resulted rapid adsorption of MB dye. It was found that equilibrium dye concentration was achieved between 1-3 minutes, depending on the adsorption temperature. The rapid adsorption, as compared to a lot of materials, showed the potential of MCC as the future of green adsorbent. The adsorption of Methylene Blue on MCC fitted well in Langmuir Isotherm, with R2 values of higher than 0.99, while fitted moderately in Freundlich Isotherm, with R2 values between 0.9224 and 0.9223. Comparatively, the adsorption of MB on MCC fitted best Langmuir Isotherm as compared to Freundlich Isotherm which monolayer adsorption occurred at the homogenous surface of MCC. This also indicated adsorbed MB molecules do not interact with each other at neighboring adsorption sites. The maximum adsorption capacity calculated from Langmuir Isotherm was found to be 4.95 mg/g. Despite the potential of MCC as green adsorbent, the challenge of low adsorption capacity has to be addressed in the future

Ionic–gelation synthesis of gadolinium doped ceria (Ce0.8Gd0.2O1.90) nanocomposite powder using sodium-alginate

Nanocomposite powders of gadolinium-doped ceria (GDC, Ce0.8Gd0.2O1.9) were synthesized via thermal treatment of the gel formed by contacting ionic solutions of sodium alginate as the jelling template and metal (gadolinium/cerium) nitrates as the starting material. The influence of calcination temperature and sodium alginate loading fraction on the properties of the synthesized GDC nanocomposite powders was investigated. Characterization was performed by energy dispersive X-ray spectroscopy, powder X-ray diffraction, thermogravimetric analysis, Field Emission Scanning Electron Microscopy, Fourier transformed infrared spectroscopy and nitrogen adsorption/desorption analysis. It was observed that the particle size and the surface area of the produced GDC nanocomposite powders are dominantly controlled by the calcination temperature, while the effect of sodium alginate loading fraction is limited by the range of the calcination temperature. In this study, the smallest mesoporous GDC nanocomposite powder with cubic fluorite structure (8 nm crystallite size and 3.05 ± 0.005 m2/g surface area) was synthesized using 2 wt. % of sodium alginate at a calcination temperature of 550 °C (for 4 h).The results of this study could help to perceive the influence of the basic processing variables on the particle size and the other physiochemical properties of GDC nanocomposite powders produced by the ionic-gelation method

Current status and policies on biodiesel industry in Malaysia as the world's leading producer of palm oil

This article discusses current status of palm oil-based biodiesel industry in Malaysia, the policies introduced and strategies for its implementation. Due to renewability, high production rate, technical feasibility and role in reducing greenhouse gases (GHG) emission, palm oil is in the right position to supply the energy needs by the incorporation into the diesel supply. As a leading producer of palm oil, Malaysia has embarked on a comprehensive palm biofuel program since 1982. It has successfully established the use of palm biodiesel blend (B5) as a suitable fuel for the transport and industrial sectors through the introduction of the National Biofuel Policy. The current scenario of biodiesel program in Malaysia, as well as biofuel policies with respect to its use, technology, export, environmental issues and implementation aspects are thoroughly discussed. The roles of the policy towards the prosperity of the stakeholders, oil price and the reduction of greenhouse gasses are also highlighted.Palm oil-based biodiesel Malaysian status National policy