Intensity Of Functional Groups Research Articles

HYDROGEN AND METHANE GAS CONTENT IN SYNGAS FROM THE PYROLYSIS OF MELALEUCA CAJUPUTI AND SHOREA WOOD

The increasing demand for energy and the depletion of fossil energy supplies require research to find renewable energy sources. Biomass is a very potential energy source and biomass gasification is a technique to produce syngas. Melaleuca Cajuputi (Gelam) and Shorea sp (Meranti) are one of the types wood plant that are widely available in Indonesia. This study aims to reveal the potential of biomass from swamp-growing plants, Melaleuca Cajuputi, and land-growing plants, Shorea, through a gasification process to produce syngas containing hydrogen and methane gas.
 Pyrolysis of biomass, Melaleuca Cajuputi and Shorea sawdust, using a fixed bed reactor at a temperature varying from 200 °C to 450 °C with a heating rate of 10 °C/minute for one hour. Hydrogen gas and methane gas resulting from pyrolysis were analyzed to determine the characteristics of the syngas produced. FTIR test was performed to support the experimental analysis.
 The experimental results show that Melaleuca Cajuputi wood has a lower peak FTIR intensity than Shorea wood. Melaleuca Cajuputi produces more hydrogen, while Shorea wood produces more methane gas. The highest hydrogen gas content was produced from Melaleuca Cajuputi and Shorea at temperatures of 315 °C at 1746 ppm and 1503 ppm at 367 °C respectively. Meanwhile, the highest methane gas content was produced by Shorea and Melaleuca Cajuputi wood, 200,000 ppm at 370 °C and 63,200 ppm at 318 °C respectively. The intensity of functional groups from biomass affects the gas produced from pyrolysis.

Iron-modified biochar reduces nitrogen loss and improves nitrogen retention in Luvisols by adsorption and microbial regulation

Nitrogen (N) loss poses a great threat to global environmental sustainability. The application of modified biochar is a novel strategy to improve soil nitrogen retention and alleviate the negative effects caused by N fertilizers. Therefore, in this study iron modified biochar was used as a soil amendment to investigate the potential mechanisms of N retention in Luvisols. The experiment comprised five treatments i.e., CK (control), 0.5 % BC, 1 % BC, 0.5 % FBC and 1 % FBC. Our results showed that the intensity of functional groups and surface structure of FBC was improved. The 1 % FBC treatment showed a significant increment in soil NO3−-N, dissolved organic nitrogen (DON), and total nitrogen (TN) content by 374.7 %, 51.9 %, and 14.4 %, respectively, compared with CK. The accumulation of N in cotton shoots and roots was increased by 28.6 % and 6.6 % with 1 % FBC addition. The application of FBC also stimulated the activities of soil enzymes related to C and N cycling i.e., β-glucosidase (βG), β-Cellobiohydrolase (CBH), and Leucine aminopeptidase (LAP). In the soil treated with FBC, a significant improvement in the structure and functions of the soil bacterial community was found. FBC addition altered the taxa involved in the N cycle by affecting soil chemical properties, especially for Achromobacte, Gemmatimonas, and Cyanobacteriales. In addition to direct adsorption, the regulation of FBC on organisms related to N-cycling also played an important role in soil nitrogen retention.

Environmental Hazard of Polypropylene from Disposable Face Masks Linked to the COVID-19 Pandemic and Its Possible Mitigation Techniques through a Green Approach

The COVID-19 outbreak again underlined plastic items’ importance in our daily lives. The public has widely utilized disposable face masks constructed of polypropylene polymer materials as effective and inexpensive personal protective equipment (PPE) to inhibit virus transmission. The consequences of this have resulted in millions of tons of plastic garbage littering the environment due to inappropriate disposal and mismanagement. Surgical masks are among them, and this study aimed to assess the biodegrading efficiency of disposable face masks using Pseudomonas aeruginosa VJ 1. This work used a bacterial strain, Pseudomonas aeruginosa VJ 1, obtained from sewage water-contaminated surface soil in Tiruchirappalli, India, to investigate the biodegradation of polypropylene (PP) face masks. The mask pieces were incubated with Pseudomonas aeruginosa VJ 1 culture in three different solid and liquid media for 30 days at 37°C. Surface changes and variations in the intensity of functional groups and carbonyl index variations were confirmed using Field Emission Scanning Electron Microscopy (FE-SEM) and Fourier Transform Infrared Spectroscopy (FTIR) analysis to ensure microbial degradation (up to 5.37% weight reduction of PP films within 30 days). These findings show that Pseudomonas aeruginosa VJ 1 could be a good choice for biodegrading PP masks without harming our health or the environment. There is a need for a novel solution for the degradation of PP. The methods and strain presented here reveal the potential biodegrading agents of PP masks.

New insight into transformation of tetracycline in presence of Mn(II): Oxidation versus photolysis

Tetracycline (TC) and Mn(II) is a common antibiotic and metal ion respectively. Nevertheless, literatures involving in the effects of Mn(II) on TC transformation are still insufficient. In this study, the kinetic experiment, spectral analysis, complexation experiment and electrochemical analysis, theoretical calculation and products detection were carried out to probe into oxidation and photolysis of TC with Mn(II). Mn(II) greatly accelerated TC oxidation, preferably tending to complex with TC at O10 – O12 or O2 – O3 site. There were a TC-Mn(II)/TC-Mn(III) redox couple and electron transfer process. Conversely, Mn(II) inhibited photolysis of TC. The photolysis of excited TC could compete with energy dissipation reactions. The electron transfer and complexation reaction easily made excited TC energy transfer, thus slowing down photolysis process. During the TC transformation, the intensity of functional groups was significantly decreased. Simultaneously, the degradation pathways mainly included eight reactions. It is a very interesting and probably overlooked phenomenon, which identifies new transformation of TC with Mn(II). This study helps to further understand fate and environmental behavior of antibiotics and metal ion.

Hydrothermal Carbonization of Waste Sugarcane Bagasse for the Effective Removal of Emerging Contaminants from Aqueous Solution

Porous carbon spheres were fabricated from sugarcane bagasse using a sustainable hydrothermal carbonization process followed by alkali impregnation inert atmosphere activation. Developed spheres were technically analysed for their chemical science, structural morphology, texture, porosity with respect to size distribution, and thermal degradation. Spheres are functionally enriched with oxygenated groups showing amorphous nature portraying as a smooth surface. After activation, intensity of functional groups is reduced due to reduction reaction by KOH thereby yielding highly rich porous carbon. The active surface area developed on spheres is 111 m2 g-1 holding pores that are mesoporous in nature. Resistance to thermal exposure using TGA showed that decomposition of hemicelluloses followed by cellulose yielded aromatized carbon-rich skeleton through thermal degradation of carboxyl and hydroxyl groups. Developed carbon was found to be effective in removing Ciprofloxacin Hydrochloride from water with maximum adsorption capacity of 110.008 mg g-1. Mechanistic removal followed pseudo-second-order kinetics along with Freundlich mode of adsorption. The presence of carboxylic and hydroxyl groups in porous carbon favoured elimination of CPF from water. The development of HTC-derived carbon helped conserving the energy thereby reducing the cost requirement.

Biofilm mediated degradation of commercially available LDPE films by bacterial strains isolated from partially degraded plastic

AbstractBiodegradation is an attractive approach for the elimination of synthetic polymers, pervasively accumulated in natural environments and generating ecological problems. The present work investigated the degradation of low‐density polyethylene (PE) by three Bacillus sp., that is, ISJ36, ISJ38, and ISJ40. The degree of biodegradation was assessed by measuring hydrophobicity, viability, and total protein content of bacterial biofilm attached to the PE surface. Although all three bacterial strains were able to establish an active biofilm community on the PE surface, ISJ40 showed better affinity toward PE degradation than the other two. Bacterial colonization and physical changes on the PE surface were visualized by scanning electron microscopy. Fourier transform infrared spectroscopy analysis revealed alteration in the intensities of functional groups along with an increase in the carbonyl bond indexes. The study results suggest that the Bacillus strain ISJ40 can be used as a potential degrader for the eco‐friendly treatment of PE waste.

Characteristics investigation on biofilm formation and biodegradation activities of Pseudomonas aeruginosa strain ISJ14 colonizing low density polyethylene (LDPE) surface

The accelerated population and industrial development have caused an extensive increase in the use of plastic products. Since polyethylene degrades slowly generating poisonous compounds, therefore, elimination of plastic from the environment is the prerequisite requirement today. Biodegradation of plastics seems to be a convenient and effective method to curb this problem. In view of this, the present study focuses on LDPE degradation capability of bacterial strain Pseudomonas aeruginosa ISJ14 (Accession No. MG554742) isolated from waste dump sites. Further, the stability of 16S rDNA of the isolate was determined by applying bioinformatics tools. For biodegradation studies, the polyethylene films were incubated with the culture of P. aeruginosa ISJ14 in two different growth medium namely Bushnell Hass broth (BHM) and Minimal Salt medium (MSM) for 60 days at 37 °C on 180 rpm. In addition, hydrophobicity and viability of bacterial isolate along with quantification of total protein content was also done. The microbial degradation was confirmed by surface modification and formation of fissures on polyethylene surface along with the variation in the intensity of functional groups as well as an increase in the carbonyl index using field emission scanning electron microscopy (Fe-SEM) and Fourier transform infrared spectrophotometry (FTIR). These results indicate that P. aeruginosa strain ISJ14 can prove to be a suitable candidate for LDPE waste treatment without causing any harm to our health or environment.

Functionalization of Rice Husks with Ortho-Phosphoric Acid Enhanced Adsorptive Capacity for Anionic Dye Removal

Rice husk is a biodegradable polymer which is quite abundant. However, its low adsorption capacity has limited its use as an adsorbent. This study has described the adsorption of methyl orange (MO) on rice husk (RH) and its H3PO4-functionalized derivative (FRH). Both adsorbents were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and Energy Dispersive X-ray (EDX). Spectra data showed shifts and reduction in intensities of functional groups in addition to appearance of a peak at 963 cm−1 in FRH. SEM and EDX images revealed changes in surface morphology with rougher cavities and increased percentage of carbon content that could influence adsorptive properties. Effects of pH, contact time, MO concentrations, adsorbent dosage, and temperatures on adsorption processes were studied. Adsorptive uptake of MO was maximum at pH 2.0 for RH, pH 5.0 for FRH, and was found to increase with increase in contact time, dosage and concentration. Langmuir isotherm was the most favourable to describe the adsorption process for RH whereas Freundlich was the most appropriate for FRH. The maximum monolayer adsorption capacity improved from 28.7 (RH) to 177.4 mgg−1 (FRH). Energies of adsorption (4.5 and 3.6 kJmol−1) indicated a physiosorption removal of MO. Pseudo second order kinetics best described the adsorption process. Both adsorption processes were spontaneous, while it was exothermic for RH, it was endothermic for FRH. Functionalization with H3PO4 enhanced the adsorptive capacity of rice husk by 519%.

Biodegradation of weathered polystyrene films in seawater microcosms

A microcosm experiment was conducted at two phases in order to investigate the ability of indigenous consortia alone or bioaugmented to degrade weathered polystyrene (PS) films under simulated marine conditions. Viable populations were developed on PS surfaces in a time dependent way towards convergent biofilm communities, enriched with hydrocarbon and xenobiotics degradation genes. Members of Alphaproteobacteria and Gammaproteobacteria were highly enriched in the acclimated plastic associated assemblages while the abundance of plastic associated genera was significantly increased in the acclimated indigenous communities. Both tailored consortia efficiently reduced the weight of PS films. Concerning the molecular weight distribution, a decrease in the number-average molecular weight of films subjected to microbial treatment was observed. Moreover, alteration in the intensity of functional groups was noticed with Fourier transform infrared spectrophotometry (FTIR) along with signs of bio-erosion on the PS surface. The results suggest that acclimated marine populations are capable of degrading weathered PS pieces.

Identification of Carbon Dots in Waste Cooking Oil

We found carbon dots (C-Dots) in waste cooking oil. The C-Dots were formed as result of heating process. The Heating process caused carbon chains on waste oil were cut off and suffered rearrangements (polymerization) of carbon chains that accompanied with the process of carbonization. Luminescence C-Dots were observed while C-Dots on waste oil was irradiated by UV Light and the emissions were radiated in the visible light area which looks yellow-greenish color. The Heating process with different temperatures caused changes in the structure and the band gap energy. Structural changes were observed from the FTIR spectrum where the intensity of functional groups C ⎯ OH, C ⎯ H and C = O on a degraded waste oil. While the band gap energy of C-Dots displaces due to hydrothermal processes with different heating temperature. The Band gap energy shifted from 0.5 eV to 2 eV at 300οC of heating temperature. This study shows that we found an alternative raw material for luminescence materials.

Impacts of Aging and Chemical Cleaning on the Properties and Performance of Ultrafiltration Membranes in Potable Water Treatment

The impacts of aging and chemical cleaning on the properties and performance of ultrafiltration membranes in potable water treatment were investigated using membrane samples from a full-scale water filtration plant. A range of analytical tools were employed to characterize various membrane attributes, encompassing flux, tensile strength, morphology, surface resident functional groups, and both organic and inorganic foulants. The results of laboratory experiments that simulated chemical cleaning sequences were consistent with those observed in the full-scale water filtration plant, in terms of their effects on the properties of the membranes. It was revealed that aging played a significant role in the deterioration of the tensile strength of the membrane media, as well as the degradation of the intensity of surface resident functional groups, which led to the accumulation of foulants. While cleaning with hypochlorite resulted in a decrease of membrane tensile strength, identical cleaning with citric acid had no such effect. The degradation of membrane tensile strength may be correlated to a decrease in the intensities of functional groups as measured by Fourier transform infrared spectroscopy (FTIR). These results suggest that the concentration of hypochlorite and the cleaning duration should both be minimized to reduce their negative impacts on membrane properties.

Effect of SHI on dielectric and magnetic properties of metal oxide/PMMA nanocomposites

Magnetic nanoparticles embedded in polymer matrices have excellent potential for electromagnetic device applications like electromagnetic interference suppression, etc. The NiO nanoparticles were synthesized by simple method. These nanoparticles were dispersed in PMMA matrix and films were prepared by casting method with varying concentrations of nickel oxide nanoparticles. These films were irradiated with 50 MeV Li +3 ions at a fluence of 5 × 10 12 ions/cm 2. AC electrical properties of pristine and irradiated samples were studied in wide frequency range. Dependence of dielectric properties on frequency, ion beam fluence and filler concentration was studied. The results reveal the enhancement in dielectric properties after doping nanoparticles and also upon irradiation, which is also corroborated with field-cooled–zero-field-cooled (FC–ZFC) susceptibility measurement in which magnetization is increased upon irradiation. The Fourier transform infrared (FTIR) spectroscopy analysis revealed the change in the intensity of functional groups after irradiation. Average surface roughness observed to change with filler concentration and also with the irradiation fluence as obtained from AFM analysis.

AC electrical properties of proton irradiated EVA films

MeV ions passing through polymeric films modify their electrical, optical and thermal properties and these changes are related to changes in the chemical structure of the polymers. Ethylene vinyl acetate (EVA) films were irradiated with 3 MeV proton beam at different fluences of 1013, 1014 and 1015 ions/cm2. AC electrical properties of pristine and irradiated samples were studied in the frequency range 100 Hz to 100 kHz by means of an LCR meter. There is an exponential increase in conductivity with log frequency and conductivity increases as fluence increases. The dielectric loss/constant is observed to change with the fluence. FTIR spectra reveals significant change in intensities of functional groups at a fluence of 1015 ions/cm2 due to scissioning of polymer chains.