Addition Of Carbonaceous Materials Research Articles

New insights of anaerobic performance, antibiotic resistance gene removal, microbial community structure: applying graphite-based materials in wet anaerobic digestion

ABSTRACT The addition of carbonaceous materials into anaerobic digestion (AD) has gained widespread attention due to their significant effects on anaerobic performance and antibiotic resistance gene (ARG) removal. This study selected graphite, graphene, and graphene oxide (GO) as additives to investigate variations in AD performance, ARG removal, microbial community diversity and structure in wet AD systems. The results indicated that the addition of graphite-based materials in wet AD systems could increase degradation of solid organic matters by 0.91%-3.41% and utilization of soluble organic fractions by 10.43%-13.67%, but could not stimulate methane production. After the addition of graphite and graphene, ARG removal rates were effectively increased to 90.85% and 94.22%, respectively. However, the total ARG removal rate was reduced to 77.46% with the addition of GO. In addition, the microbial diversity in the wet AD process was enhanced with the addition of GO only, graphite and graphene led to a reduction in it. As for bacterial community, graphite and graphene increased the abundance of Thermotogae from 43.43% to 57.42% and 58.74%, while GO increased the abundance of Firmicute from 49.90% to 56.27%. For the archaeal community, the proportion of hydrogenotrophic methanogens was improved when adding each graphite-based material; however, only GO increased Methanosaeta that was acetoclastic methanogens. Finally, methanogens were found as the ARG host, and ARGs that belong to the same subtype might exist in the same host bacteria.

Preparation and Characterization of UV-LED Curable Acrylic Films Containing Biochar and/or Multiwalled Carbon Nanotubes: Effect of the Filler Loading on the Rheological, Thermal and Optical Properties.

UV-LED curable coatings represent an up-to-date attractive field due to the high curing efficiency even in the presence of high filler loadings, as well as to the absence of infrared wavelengths that may negatively impact on heat-sensitive substrates. The addition of carbonaceous materials, such as biochar (BC) and/or multiwalled carbon nanotubes (MWCNTs) could positively improve both the rheological and thermal properties. In this study we report on the synthesis and characterization of carbon-reinforced films containing nanometric (MWCNTs) and micrometric (BC) carbon-based materials. We analyze the rheological properties of the UV-LED curable dispersions, as well as the thermal and optical properties of the resulting films, establishing some correlations between filler dispersion/loading with the main observed properties.

Synthesis of micro carbonaceous material by pyrolysis of rubber wood and its effect on properties of urea-formaldehyde (UF) resin

Micro sized carbonaceous materials were synthesized by pyrolysis of rubber wood fibers and their dispersion in urea formaldehyde (UF) was investigated. The carbonaceous material reinforced in UF has been prepared with a weight concentration up to 5%. The uniform dispersion of the carbonaceous material in the UF was achieved by mechanical stirring. All resin hybrids were characterized by solution rheology, Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffractometry (XRD) while the dispersion of carbonaceous materials was analyzed by scanning electron microscopy (SEM). FTIR spectroscopy results showed that carbonaceous materials can make hydrogen bonds with UF resins. The X-ray-based measurement of the crystallinity index (CrI) indicated that carbonaceous material increased the crystallinity of UF resin, whereas the maximum value of CrI was observed at UF-1 i.e., 85.7%. Curing reactions were examined with differential scanning calorimetry (DSC), and it was observed that the curing temperature of UF resin is affected by the addition of carbonaceous materials. Thermo-gravimetric analysis (TGA) revealed that carbonaceous materials have little effect on the thermal stability of the resin. Wood particleboards were fabricated and their performance was measured. The internal bonding strength and the modulus of rupture were measured for the particle boards, and a maximum at a 1% weight concentration was observed. The formaldehyde content of particle boards decreased with the addition of carbonaceous materials. At a 1% weight concentration, a maximum reduction of formaldehyde content was obtained using the perforator method.

Improving the hydrogenation properties of AZ31-Mg alloys with different carbonaceous additives by high energy ball milling (HEBM) and equal channel angular pressing (ECAP)

In this study, the hydrogen storage performance of commercial AZ31-Mg alloys combined with various allotropes of carbon was investigated and the microstructural modifications with respect to plastic deformation and high energy milling techniques investigated, with the aim of obtaining enhanced hydrogen storage efficiency. The hydrogen storage performance of alloys prepared with different weight ratios of carbonaceous materials as a catalyst was monitored in order to explore the effective improvement in hydrogen storage performance through microstructural modification. Additionally, the effects of different processing methods such as equal channel angular pressing (ECAP) and high energy ball milling (HEBM) were also observed. AZ31 Mg based composites with various carbon additives were produced through gravity resistance casting and their micrographic structures examined through optical Microscopy (OM), X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The average particle size distributions of the sample powders were also measured. The rate of hydrogenation kinetics was calculated by a Sievert's type apparatus. Significant enhancement of the hydrogenation performance was obtained with the addition of carbonaceous materials. Overall, the hydrogen storage performance after ECAP deformation of the AZ31-3CB (carbon Black) composite showed a gain in the maximum capacity of 6.72 ± 0.05 wt%. Similar, after milling of the AZ31-3G (Graphene) composite materials, a maximum potential capacity of 6.83 ± 0.04 wt% was attained within 792 ± 144.34 s, with desorption of the entire H2 content in 143.2 ± 26.09 s. The obtained results revealed significant improvement in the hydrogen storage capacity of AZ31-Mg alloys with the addition of carbon materials and with respect to plastic deformation and milling techniques.

Exploring the main function of reduced graphene oxide nano-flakes in a nickel cobalt sulfide counter electrode for dye-sensitized solar cell

Abstract Addition of carbonaceous materials into transition metal sulfide counter electrode (CE) of a dye-sensitized solar cell (DSSC) is a common method to improve the performance of the CE and consequent photovoltaic performance. This improvement is almost without exception attributed to the improvement of overall conductivity after the carbonaceous material addition; however, the root function of these carbonaceous materials in promoting the solar cell efficiency is seldom discussed. In this study, highly crystallized nickel cobalt sulfide (NCS) micro-particles were mixed with a small portion of home-made reduced graphene oxide (rGO) nano-flakes. This NCS/rGO hybrid is subjected to extensive characterizations including X-ray diffraction, Raman spectroscopy, field emission scanning microscopy and electrochemical impedance spectroscopy. It is found that the rGO acts bi-functionally including a co-catalyst in accelerating the tri-iodide reduction for the main NCS catalysts, conductivity promotor to decrease the series resistance of the CE. Proved by electrochemical impedance spectroscopy, it is confirmed that the decrease in series resistance is less insignificant than that in charge transfer resistance, indicating rGO functions more profoundly as a co-catalyst than as a conductivity promotor. Moreover, an argument to highlight the requirement of a CE in a dim-light optimized DSSC is also proposed.

Copper ions removal from liquid phase by polyethersulfone (PES) membranes functionalized by introduction of carbonaceous materials

The method of synthesis of polymeric membranes based on polyethersulfone (PES) and modified by addition of carbonaceous materials (char or activated carbon) is presented and their potential application for removal of copper ions from liquid phase are examined. The addition of carbon brings about changes in the content of the surface oxygen group but has no significant effect on the chemical character of the groups, and acidic groups dominate. After filtration of a copper solution the total content of surface oxides considerably increases but the acidic groups remain dominant. Modification of PES membrane by addition of carbonaceous materials was found to strongly increase the membrane effectiveness in copper ions removal. The membrane with addition of char is the most effective at low copper concentrations, while the membrane with addition of activated carbon is the best at high concentrations of copper ions.

Thermal detoxification of hazardous metal sludge by applied electromagnetic energy

Industrial wastewater sludge was treated by microwave processes to enhance the stabilization of laden copper. The effects of additives, processing time, microwave adsorbents, moisture content, reaction atmosphere, and cooling gas were investigated. The stabilization results were significantly enhanced by metal powder additives, prolonged microwave processing time, proper moisture content, the addition of carbonaceous materials, and a reaction environment with inert gas. It was also found that the moisture content would increase the homogeneity of applied microwave energy, and thus achieve a better overall efficiency between stabilizing agents and copper. The added metal powders may reduce Cu(II) to Cu(0) in the sludge or TCLP. The resulting thermal energy of microwave radiation, and microarcing process and the oxidation heat of Al powder may also assist the transformation of Cu(II) into CuO and CuAl 2O 4 phases. Part of the sludge was vitrified within inert gas environment when the processing time was longer than 18 min and active carbon dosage was more than 3 g. Reduction reactions also occurred in the hybrid microwave processes, leading to the reduction of sulfates and metal ions, and the formation of Cu 2S and FeS. Moreover, the microwave radiation can also enhance the feasibility of co-treating of inorganic and organic solid waste.

ペレット焼成プロセスにおける炭材内装技術の開発

ペレット焼成プロセスにおける炭材内装技術の開発

(391)塩素処理による窯業原材料脱鉄精製の研究(第3報)陶磁器原料脱鉄の際の炭素質物添加の効果

(391)塩素処理による窯業原材料脱鉄精製の研究(第3報)陶磁器原料脱鉄の際の炭素質物添加の効果