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1.
BMC Chem ; 18(1): 107, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38816730

ABSTRACT

Star-like structural compounds were synthesized from different moles % of either dodecyl acrylate or triethylenetetramine using a one-pot commercial synthesis technique. The polymers that were created had various terminations. Fourier Transform Infrared (FTIR) spectroscopy and 1HNMR were used to verify the produced polymers' chemical composition with different terminations. Furthermore, by analysis of Dynamic Light Scattering (DLS), the size and distribution of the synthesised branched polymers were evaluated. Using a Gel-permeation chromatograph, the modified hyperbranched polymer's molecular weight, synthesized with various end points, were assessed. The unorganized structured prepared compounds with various molar feed ratios dodecyl acrylate: triethylenetetramine (DDA: TETA) was designed as A, B, C, D and E. Moreover, the synthesized additives function as viscosity index improvers (VII). As the concentration of polymeric additives increases, it leads to higher VI values. Similarly, with the increase in percentage of triethylenetetramine in the prepared hyperbranched polymers, the VI also increases. Notably, the most effective VI achieved is (E) = 212. It is noteworthy that all the synthesized hyperbranched polymers exhibited Newtonian behavior in the rheological study.

2.
Environ Sci Pollut Res Int ; 31(6): 8369-8386, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38172321

ABSTRACT

Different petroleum operations produce huge amount of oil sludge annually. For instance, US EPA estimates the annual sludge production of each US refinery of 30,000 tons, while the average oily sludge produced from petrochemical industries in China is estimated about 3 million tons per year. In the last year, our center could recover about 30,206 barrels of raw oil from 32,786 barrels of tank bottom sludge (TBS) for different petroleum companies. This sludge causes huge economic losses besides its negative environmental impacts. The accumulation of sludge in the tanks results in reducing the tanks' capacity for storing liquid crude, accelerating the corrosion of the tanks, delay in the production schedule, and disturbing the whole production operation. There are diverse treatment methodologies such as solvent treatment, addition of certain chemicals, and centrifuging. Of course, the environmental regulations and the overall cost limitations are very important in deciding the preferred applicable method(s). Although several works handled the problem of sludge deposition and treatment from different aspects, we intend to introduce a different work. First, composition, formation, types, and properties of TBS were reviewed. Then, environmental and economic problems caused by TBS were revised. At last, different methodologies applied for treatment of oily TBS to recover oil and safe disposal of hazardous remains were investigated focusing on the most straightforward and environmentally friendly protocols. It is expected that this review attracts the experts in petroleum chemistry, and other relevant fields and provides a comprehensive understanding of current sludge control and treatment research.


Subject(s)
Petroleum , Petroleum/analysis , Sewage , Oils , Solvents , China
3.
ACS Omega ; 8(4): 3872-3881, 2023 Jan 31.
Article in English | MEDLINE | ID: mdl-36743014

ABSTRACT

One of the most widely used plastics in the world's rapidly urbanizing population is polyethylene (PE). Globally, there is a growing demand for plastics. Polyethylene plastics do pollute and harm the environment. Although polyethylene is said to be nonbiodegradable, any chemical deterioration can take hundreds of years. This study intends to improve the crude oil property, precisely its pour point, by using polyethylene derived from waste products with magnetic nanoparticles (MNPs) and applying it to heavy and light crude oils. Forty crude oil samples were prepared by changing the PE additive concentration from 0.25 to 2% with 0-2.0% MNP concentration. Dynamic light scattering (DLS), gas chromatography, and photomicrographic techniques were employed during the study. DLS results revealed that nanoparticles of heavy (B) crude oil have bigger particle sizes than light (A) crude oil samples, and the overall distribution of the added nanoparticles was much better in light crude oil than in heavy crude oil. The photomicrographic results revealed that the treated samples using additives provided a significant wax crystal reduction compatible with the provided pour point results. The prepared sample of the treated light (A) crude oil provided a more extraordinary rheology performance than the heavy (B) crude oil. Moreover, prepared crude oil samples with PE additives and MNPs are effective as pour point depressants.

4.
ACS Omega ; 6(47): 31926-31934, 2021 Nov 30.
Article in English | MEDLINE | ID: mdl-34870015

ABSTRACT

Sustainability metrics have been established that cover the economic, social, and environmental aspects of human activities. Reduce, reuse, and recycle (3R) strategy targets solid waste management in the waste generation sectors. The purpose of this work is to study the possibility of using various plastic wastes containing high-density polyethylene (HDPE) and high-density polyethylene nanoclay (PMON) as polymer additives to modify lubricating oil. The structure of these additives was elucidated by Fourier transform infrared (FTIR) spectra, and the particle size of PMON was determined by dynamic light scattering (DLS). The thermal stability of HDPE and nanoclay HDPE (PMON) was studied, which showed higher thermal stability, and these additives completed degradation above 500 °C. The performance of HDPE and nanoclay HDPE (PMON) in lubricating oil was evaluated as pour point depressants by standard ASTM methods. The results showed that the efficiency of these additives increases with the decrease in the dose of these additives and lubricating oil treated with HDPE at 0.25% dosage lowers PPT to -30 °C, while lubricating oil treated with nanoclay HDPE (PMON7) at 0.25% dosage reduces PPT to -36 °C. Photomicrographic analysis was conducted to study accumulations and modifications in the wax crystal morphology in lube oil without and with HDPE and nanoclay HDPE (PMON7). Photomicrographs revealed that wax morphology changes due to effective pour point depressants on crystal growth.

5.
Materials (Basel) ; 13(21)2020 Oct 30.
Article in English | MEDLINE | ID: mdl-33143385

ABSTRACT

There is a pressing demand to synthesize polymers that have antibacterial and antifungal properties. The aim of this study was to synthesize a crosslinked hydrophilic terpolymer with acrylamide, acrylonitrile, acrylic acid, acrylamido-2-methylpropane sulphonic acid and ethylene glycol dimethacrylate as a crosslinker. The chemical structure and thermal stability of the prepared cross-linked terpolymers were confirmed by spectroscopic and thermal analyses. Moreover, the swelling experiments were performed to investigate their swelling capacity. Furthermore, the efficiency of the synthesized cross-linked polymer gels was assessed as an antimicrobial agent against Gram-positive, Gram-negative bacteria and fungal strains. The synthesized polymers showed broad inhibition effect, with more antibacterial activity by the AM4 polymer sample containing high percentage of acrylonitrile monomer in the prepared terpolymers (4 mol ratio of acrylic acid: 1 mol ratio of acrylamide: 16 mole ratio of acrylonitrile against Gram negative bacterial strain), while sample M3 terpolymer (1 mol ratio of acrylamide: 1 mole ratio acrylonitrile: 3 mole ratio of acrylamido-2-methylpropane sulphonic acid) showed a promising anti-fungal activity.

6.
Materials (Basel) ; 12(21)2019 Nov 03.
Article in English | MEDLINE | ID: mdl-31684135

ABSTRACT

In the past few years, the development of hydrogel properties has led to the emergence of nanocomposite hydrogels that have unique properties that allow them to be used in various different fields and applications such as drug delivery, adsorption soil containing, tissue engineering, wound dressing, and especially antimicrobial applications. Thus, this study was conducted in order to fabricate a novel crosslinked terpolymer nanocomposite hydrogel using the free radical copolymerization method based on the usage of 2-acrylamido-2-methylpropane sulfonic acid (AMPS), acrylamide (AAm), acrylonitrile (AN), and acrylic acid (AA) monomers and iron oxide (Fe3O4) magnetic nanoparticles and using benzoyl peroxide as an initiator and ethylene glycol dimethacrylate (EGDMA) as a crosslinker. The structure of the synthesized composite was confirmed using Fourier transform infrared (FTIR) spectroscopy and x-ray powder diffraction (XRD) measurements. Furthermore, the surface morphology and the magnetic nanoparticle distributions were determined by scanning electron microscopy (SEM) measurement. In addition, the swelling capacity of the hydrogel nanocomposite was measured using the swelling test. Lastly, the efficiency of the produced composite was evaluated as an antimicrobial agent for Gram-positive and Gram-negative bacterial strains and a fungal strain.

7.
Molecules ; 18(1): 190-203, 2012 Dec 24.
Article in English | MEDLINE | ID: mdl-23262448

ABSTRACT

Nanogels of a binary system of carboxymethyl chitosan (CMCh) and poly- (vinyl alcohol) PVA, were successfully synthesized by a novel in situ process. They were also characterized by various analytical tools like Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and X-ray diffraction (XRD). They were studied for their unique swelling properties in water and different pH solutions. They were also investigated for their great ability to capture or isolate bacteria and fungi from aquatic environments.


Subject(s)
Anti-Infective Agents/chemistry , Chitosan/analogs & derivatives , Gels/chemical synthesis , Nanostructures/chemistry , Anti-Infective Agents/chemical synthesis , Aspergillus flavus/drug effects , Candida albicans/drug effects , Chitosan/chemical synthesis , Escherichia coli/drug effects , Microscopy, Electron, Transmission , Polyvinyl Alcohol/chemical synthesis , Spectrophotometry, Infrared , Spectroscopy, Fourier Transform Infrared , Staphylococcus aureus/drug effects , X-Ray Diffraction
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