A Freestanding Chitin-Derived Hierarchical Nanocomposite for Developing Electrodes in Future Supercapacitor Industry

Crustacean cuticles are receiving extensive attention for its potential in developing environmentally friendly and high energy density electrodes for supercapacitor applications. In the current work, the demineralized tergite cuticle of mantis shrimp was employed as a precursor for the fabrication porous biochar. The structural benefits of the cuticle, including the hierarchical nanofiber networks, and the interpenetrating pore systems were maximumly retained, providing a high carbon content and specific surface area scaffold. Graphene oxide sheets were deposited across the biochar through the pore canal systems to further increase the conductivity of the biochar, forming a novel freestanding carbon composite. Throughout the modification process, the material products were examined by a range of methods, which showed desired structural, chemical and functional properties. Our work demonstrates that high performance carbon materials can be manufactured using a simple and green process to realize the great potential in energy storage applications.

A Novel Approach to Charcoal Fine Waste: Sustainable Use as Filling of Polymeric Matrices

This study aims to evaluate charcoal fines as potential reinforcing agents in biocomposites. Charcoal has both high carbon content and surface area depending on the manufacturing temperatures. Charcoal is a common residue in the coal industry that we propose using it to reinforce filling agents in several matrices in order to add value to this residue. This study investigated charcoal fines when using three pyrolysis temperatures (400, 600, and 800°C) to identify the most suitable charcoal to be used as raw materials in producing carbon biocomposites. We evaluated apparent density, porosity, morphology, and immediate chemical composition, and then performed a Fourier-transform infrared spectroscopy (FTIR) and an X-ray photoelectron spectroscopy (XPS). Charcoal fines produced at 800°C showed promising results as a polymeric matrix filling due to their higher porosity (81.08%), fixed carbon content (96.77%), and hydrophobicity.

High Temperature Continuous Gas Purification and Graphitization System and Process for Carbon Particulate Materials

With the continuous development of modern science and technology, more and more new materials have been applied to production and life. As a new material, carbon granular material is made of carbon, graphite materials and other various raw materials with high carbon content through a series of processing technologies. China is one of the most widely used carbon materials in the world. The purpose of this paper is to optimize and enhance the application effect of carbon materials and promote the construction of a new economic model of energy conservation and emission reduction in China. The specific research is as follows:

Characteristics and agrarian properties of biochar derived from pyrolysis and co-pyrolysis of rubberwood sawdust and sewage sludge for further application to soil improvement

This study investigated the characteristics of biochars derived from pyrolysis of rubberwood sawdust and sewage sludge, and co-pyrolysis of these feedstocks at the ratios of 50:50 and 75:25. All feedstocks were pyrolyzed at 550°C in slow pyrolysis with a moving bed pyrolysis reactor. Then, the investigated characteristics of biochar samples were determined and are reported. The rubberwood sawdust biochar (RWSB) had a higher in carbon content (86.70 wt%) and was lower in oxygen content (7.89 wt%), while sewage sludge biochar (SSB) had a higher ash content (65.61 w%) and a low carbon content (24.27 wt%). The weight losses of biochars were observed in TGA while the DTG graphs show degradation rate of biochar produced in pyrolysis specific conditions. RWSB had a lower content of Si, Fe, K, Na and P than SSB as observed by XRF. The pH of RWSB, SSB and the blends (50:50, 75:25) of biochars was in the range 8.41–10.02. High carbon content of the biochar confirms potential for its use in carbon sequestration. The large pore volumes and specific surface areas of biochars were found by SEM and BET. The available functional groups in biochars were C–O, C = C, and C–H as confirmed by FTIR. Water holding capacity (WHC) and water releasing ability (WRA) of RWSB, SSB, and the blends (50:50 and 75:25) of biochars were 1.01–3.08 (mL/g) and 1.19–52.42 (wt%), respectively. In this study, our results show that blending woody and non-woody based biochars can help address nonpoint source contaminants in environment. So, these all findings should develop as tune to parameters of thermal degradation of biomass and bio-biowaste with sustain and eco-friendly biochar production.

Organic Matter and Associated Minerals on the Dwarf Planet Ceres

Ceres is the largest object in the main belt and it is also the most water-rich body in the inner solar system besides the Earth. The discoveries made by the Dawn Mission revealed that the composition of Ceres includes organic material, with a component of carbon globally present and also a high quantity of localized aliphatic organics in specific areas. The inferred mineralogy of Ceres indicates the long-term activity of a large body of liquid water that produced the alteration minerals discovered on its surface, including ammonia-bearing minerals. To explain the presence of ammonium in the phyllosilicates, Ceres must have accreted organic matter, ammonia, water and carbon present in the protoplanetary formation region. It is conceivable that Ceres may have also processed and transformed its own original organic matter that could have been modified by the pervasive hydrothermal alteration. The coexistence of phyllosilicates, magnetite, carbonates, salts, organics and a high carbon content point to rock–water alteration playing an important role in promoting widespread carbon occurrence.

BIOGEOCHEMICAL AND MECHANICAL CHARACTERIZATION OF THE LANDFILL FRACTION GENERATED BY MECHANICAL WASTE SORTING

As the resource recovery from mixed waste streams are performed, new mixed waste streams are generated. Some of these waste streams does not fit well to existing waste management options, for example, they may hold a to low heating value to sustain combustion and they may have a too high carbon content to be accepted at non-hazardous landfills. Also various health and pollution risks may arise as well as practical handling issues due to the physical properties of such wastes. One such waste is the under sieve fraction generated when recovering metals and fuel from mixed waste streams using mechanical and magnetic separation tools. Such mechanical sorting is typically used for mixed wastes of different properties and particle sizes, such as houshold bulky wastes, construction and demolition waste, and at landfill mining materials. In this work, we examine the properties of one case of mechanical sorting of bulky wastes, including construction and demolition wastes. We analyse a broad spectrum of chemical, physical, and mechanical properties as well as some biological. Based on the data we develop recommendations for landfilling, what potential problems might arise and how to counteract them.

Mesofauna at the Soil-Scree Interface in a Deep Karst Environment

The community patterns of Collembola (Hexapoda) were studied at two sites along a microclimatically inversed scree slope in a deep karst valley in the Western Carpathians, Slovakia, in warm and cold periods of the year, respectively. Significantly lower average temperatures in the scree profile were noted at the gorge bottom in both periods, meaning that the site in the lower part of the scree, near the bank of creek, was considerably colder and wetter compared to the warmer and drier site at upper part of the scree slope. Relatively high diversity of Collembola was observed at two fieldwork scree sites, where cold-adapted species, considered climatic relicts, showed considerable abundance. The gorge bottom, with a cold and wet microclimate and high carbon content even in the deeper MSS horizons, provided suitable environmental conditions for numerous psychrophilic and subterranean species. Ecological groups such as trogloxenes and subtroglophiles showed decreasing trends of abundance with depth, in contrast to eutroglophiles and a troglobiont showing an opposite distributional pattern at scree sites in both periods. Our study documented that in terms of soil and subterranean mesofauna, colluvial screes of deep karst gorges represent (1) a transition zone between the surface and the deep subterranean environment, and (2) important climate change refugia.

Effect of Temperature on Calorific Value of Pyrolyzed Empty Fruit Bunch (Efb) Derived Biochar

The residues from the oil palm industry are the main contributors to biomass waste in Malaysia, and these wastes require extra attention with respect to handling. A survey of the literature indicates that most of them are handled with unsatisfactory practices that negatively impact the environment. Therefore, it is very important that they be utilized for more beneficial purposes, particularly in the context of the development of biofuels via pyrolysis technology. Due to its high carbon content, rich in lignin and low cost, empty fruit bunch (EFB) shows potential to be a good precursor for the production of biochar. The pyrolysis temperature greatly affects biochar properties and its potential usage. Many researches work on biochar have been carried out to assess its potential by investigating its characteristics. The most common thermochemical technique to produce biochar is pyrolysis, during which the organic components are decomposed at adjustable temperature in a nitrogen-limited atmosphere. The focus of this study is to identify the effect of temperature (300, 350, 400, 450 and 500 °C) on calorific value of pyrolyzed EFB derived biochar. Eight experimental runs were conducted. The results were completely analyzed by Analysis of Variance (ANOVA). The model was statistically significant. The factor studied which temperature was significant with p-values < 0.0001. The value of R2 was 0.9633 which indicated that the temperature showed high correlation to the calorific value of biochar from EFB pyrolysis process. A quadratic model equation was developed and employed to predict the highest theoretical calorific value. The maximum biochar calorific value was achieved at pyrolysis temperature of 500 °C. Char yield was obtained highest at 300°C around 53.36 wt% and started to decrease as temperature increase. Result of this experiment revealed that the calorific value of biochar increases as the temperature increases while the yield percentage of biochar decreases as the temperature increases. The yield of biochar decreases with temperature because of the secondary tar reactions of the volatiles, such as thermal cracking, that favors the increase of gas yield.

Microstructure and Properties of SLM High Speed Steel

Selective laser melting (SLM) is a commonly used laser powder bed technique where the final properties are influenced by many different powder related properties, such as particle size distribution, chemical composition and flowability. In applications where high hardness, wear resistance, strength and good heat properties are required, high speed steels (HSS) are widely used today. HSS has high carbon content and are therefore considered as unweldable. The rapidly growing implementation of AM technologies has led to a growing range of new applications and demands for new alloys and properties. The interest in being able to manufacture HSS by SLM without cracking is therefore increasing. In SLM, it is possible to preheat the base plate to a few hundred degrees Celsius which has been used for HSS and proved successful due to reduced thermal gradients. In this study, the properties of SLM produced high speed steel PEARL Micro&reg;2012 with a carbon content of 0.61 wt.-% have been investigated and compared to those of a forged and rolled PM-HIP counterpart ASP&reg;2012.