Polyethylene Terephthalate Degradation by Microalga Chlorella vulgaris Along with Pretreatment

2020 ◽  
Vol 57 (3) ◽  
pp. 260-270
Author(s):  
Wajeeha Falah ◽  
Fu-Jia Chen ◽  
Bibi Saima Zeb ◽  
Malik Tahir Hayat ◽  
Qaisar Mahmood ◽  
...  

The current research explored the potential of microalgal species Chlorella vulgaris and Pretreatment to remediate plastic waste. It was concluded from the results that Pretreatment had a marked effect on the cracking and alteration of plastic polymer, which helped to grow microbial species on the cracked surface as evident by Compound Microscopy (CM), Scanning Electron Microscopy (SEM), and Fourier Transformed Infrared Spectroscopy (FTIR) analysis. FTIR data also supported the notion that in the absence of any pretreatment, the microbial species were not able to mediate plastic biodegradation efficiently as the nature of functional groups was different in the presence and absence of Pretreatment. GCMS analysis revealed that the microbial specie could produce the biodegradation products which were likely to be found in the structure of PET, including alkanes ester, fatty acids, benzoic acid, and aromatics and the most toxic product of biodegradation is Bis (2-Ethyl hexyl phthalate), which is the biodegradation product of toxic ingredient of plastics that is phthalic acid.

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1801
Author(s):  
Rafał Oliwa ◽  
Joanna Ryszkowska ◽  
Mariusz Oleksy ◽  
Monika Auguścik-Królikowska ◽  
Małgorzata Gzik ◽  
...  

We investigated the effect of the type and amount of expandable graphite (EG) and blackcurrant pomace (BCP) on the flammability, thermal stability, mechanical properties, physical, and chemical structure of viscoelastic polyurethane foams (VEF). For this purpose, the polyurethane foams containing EG, BCP, and EG with BCP were obtained. The content of EG varied in the range of 3–15 per hundred polyols (php), while the BCP content was 30 php. Based on the obtained results, it was found that the additional introduction of BCPs into EG-containing composites allows for an additive effect in improving the functional properties of viscoelastic polyurethane foams. As a result, the composite containing 30 php of BCP and 15 php of EG with the largest particle size and expanded volume shows the largest change in the studied parameters (hardness (H) = 2.65 kPa (+16.2%), limiting oxygen index (LOI) = 26% (+44.4%), and peak heat release rate (pHRR) = 15.5 kW/m2 (−87.4%)). In addition, this composite was characterized by the highest char yield (m600 = 17.9% (+44.1%)). In turn, the change in mechanical properties is related to a change in the physical and chemical structure of the foams as indicated by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis.


2013 ◽  
Vol 448-453 ◽  
pp. 3041-3045
Author(s):  
Fei Bi ◽  
Xiang Ting Dong ◽  
Jin Xian Wang ◽  
Gui Xia Liu ◽  
Wen Sheng Yu

PVP/[Y(NO3)3+Al (NO3)3] composite nanobelts were fabricated via electrospinning combined with sol-gel process and novel structure of Y3Al5O12(denoted as YAG for short) nanobelts have been obtained after calcination of the relevant composite nanobelts. The structural properties were characterized by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). XRD analysis indicated that the composite nanobelts were amorphous, and YAG nanobelts were cubic in structure with space group Ia3d. FTIR analysis manifested that pure YAG nanobelts were formed at 900oC. SEM analysis and histograms revealed that the width of the composite nanobelts and YAG nanobelts were 3.5 μm and 2.4 μm, and the thickness were 240 nm and 112 nm, respectively, under the 95% confidence level. The formation mechanism of YAG nanobelts was discussed in detail.


2017 ◽  
Vol 264 ◽  
pp. 148-151
Author(s):  
Amirah Hulwani Mohd Zain ◽  
Mohamad Kahar Ab Wahab

The effect of modified thermoplastic starch (TPS) with organic acid was studied. In presence of ascorbic acid (AATPS) and glycerol (GTPS) along with mechanical process, a native starch granule was transform into a continuous phase as shown by scanning electron microscopy (SEM). Reaction of ascorbic acid (AA) with starch induced to the formation of the ester bond, which improved moisture resistivity of TPS was proven by the determination degree of substitution (DS) and moisture absorption test. The formation of ester bond was identified by using FTIR analysis. The DS values were ranging from 0 to 0.052, respectively, with the increase of AA content.


2019 ◽  
Vol 14 ◽  
pp. 155892501984322 ◽  
Author(s):  
Chengbo Huang ◽  
Ying Liu ◽  
Zhiguang Li ◽  
Rong Li ◽  
Xuehong Ren ◽  
...  

The main objective of this study was to develop antibacterial materials based on polyacrylonitrile for potential application in protective face masks to combat airborne pathogens. To achieve biocidal properties, 1-chloro-2, 2, 5, 5-tetramethyl-4-imidazolidinone as a kind of N-halamine was introduced into the polyacrylonitrile nanofibers by an electrospinning technique to form nanofibers by an electrospinning technique to form polyacrylonitrile/1-chloro-2, 2, 5, 5-tetramethyl-4-imidazolidinone-5% nanofibers. Scanning electron microscopy and Fourier transformed infrared spectroscopy were employed to characterize the structure of nanofibers. The antimicrobial efficacies of electrospinning nanofibers with 1-chloro-2, 2, 5, 5-tetramethyl-4-imidazolidinone against both Staphylococcus aureus and Escherichia coli O157:H7 were evaluated at different contact times. The antimicrobial efficacies against bioaerosol of S. aureus were also performed. The polyacrylonitrile/1-chloro-2, 2, 5, 5-tetramethyl-4-imidazolidinone-5% nanofibers possess excellent antimicrobial efficacies against bacteria bioaersol, and it has good air permeability.


2012 ◽  
Vol 488-489 ◽  
pp. 506-510 ◽  
Author(s):  
Sikander Rafiq ◽  
Zakaria Man ◽  
Abdulhalim Maulud ◽  
Nawshad Muhammad ◽  
Saikat Maitra

Composite membranes were prepared by incorporating inorganic silica nanoparticles into blends of polysulfone/polyimide (PSF/PI) membranes via sol-gel route. Morphological structures of the developed membranes were carried out by scanning electron microscopy (SEM). Spectroscopic analysis of the hybrid membranes were done by fourier transform infrared spectroscopy (FTIR) analysis. Differential scanning calorimetry (DSC) analysis shows that the glass transition temperature (Tg) increased from 209oC to 238oC in the hybrid membranes followed by thermogravimetric analysis (TGA) that showed significant improvement in thermal stability of the developed membranes.


2013 ◽  
Vol 295-298 ◽  
pp. 1547-1549 ◽  
Author(s):  
Zhi Qiang Ning

The composition and property of the boron mud is investigated by X-ray diffractometry (XRD), scanning electron microscope (SEM), thermogravimetry (TG), differential thermal analysis (DTA) and fourier transformed infrared spectroscopy (FITR). The mineral components of the boron mud are magnesite (MgCO3)、forsterite (Mg2SiO4)、hematite (Fe2O3)、dolomite (CaMg(CO3)2) and a small amount of magnesium sulfate and lizardite((Mg,Al)3[(Si,Fe)2O5](OH)4)). The decomposition reaction of the boron mud can be carried on at 400~600°C, and silicate of the boron mud can reaction with NaOH with the increase of temperature to about 1000°C.


1988 ◽  
Vol 66 (1) ◽  
pp. 125-129 ◽  
Author(s):  
E. Bermadinger ◽  
D. Grill ◽  
P. Golob

The difference in vigour between Picea abies (L.) Karst. and Abies alba Mill, in an area exposed to fine dust containing MgO is reflected in scanning electron microscope studies of the needle surfaces. The greater vitality of the silver fir is correlated with intact wax structures and a somewhat lower dust load. In contrast, the spruce reveals a marked effect on the epicuticular wax by a heavy fine-dust load. Possible causes and physiological consequences are discussed.


2017 ◽  
Vol 885 ◽  
pp. 123-128
Author(s):  
Mariann Kollár ◽  
Gabriella Zsoldos ◽  
Tamás Szabó ◽  
Kornél Szóda

Fourier Transformed Infrared Spectroscopy (FTIR) was used to study the effect of water immersion of guar gum, gelatin and pektin films. Animal-derived gelatin, citrus-derived pektin and natural guar gum made from guar seeds was used to manufacture thin films (using a 2% concentration starting solution) by casting. The biodegradable polymer films were immersed in distilled water before FTIR analysis to absorb water. The immersion time varied between 1 to 15 sec for not to make hydrocolloids, only observe swelling. After 20 sec the biofilms effectively dissolved in the distilled water.


2011 ◽  
Vol 36 (3) ◽  
pp. 293-303 ◽  
Author(s):  
AD Loguercio ◽  
D Salvalaggio ◽  
AE Piva ◽  
CA Klein-Júnior ◽  
M de LR Accorinte ◽  
...  

SUMMARY Objectives To evaluate the effect of adhesive temperature on the resin-dentin bond strength (μTBS), nanoleakage (NL), adhesive layer thickness (AL), and degree of conversion (DC) of ethanol/water- (SB) and acetone-based (PB) etch-and-rinse adhesive systems. Methods The bottles of the two adhesives were kept at each temperature (5°C, 20°C, 37°C, and 50°C) for 2 hours before application to demineralized dentin surfaces of 40 molars. Specimens were prepared for μTBS testing. Bonded sticks (0.8 mm2) were tested under tension (0.5 mm/min). Three bonded sticks from each tooth were immersed in silver nitrate and analyzed by scanning electron microscopy. The DC of the adhesives was evaluated by Fourier transformed infrared spectroscopy. Results Lower μTBS was observed for PB at 50°C. For SB, the μTBS values were similar for all temperatures. DC was higher at 50°C for PB. Higher NL and thicker AL were observed for both adhesives in the 5°C and 20°C groups compared to the 37°C and 50°C groups. The higher temperatures (37°C or 50°C) reduced the number of pores within the adhesive layer of both adhesive systems. Conclusions It could be useful to use an ethanol/water-based adhesive at 37°C or 50°C and an acetone-based adhesive at 37°C to improve adhesive performance.


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