Green and Sustainable Chemistry

Journal Information
ISSN / EISSN : 2160-6951 / 2160-696X
Current Publisher: Scientific Research Publishing, Inc. (10.4236)
Former Publisher:
Total articles ≅ 206
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Latest articles in this journal

Yutaka Okada, Ryuichi Maeda
Green and Sustainable Chemistry, Volume 11, pp 1-8; doi:10.4236/gsc.2021.111001

Abstract:
Microwave-assisted reactions are an environmentally friendly approach for synthesizing organic compounds. In this study, oximation of acetylferrocene and acetophenone was conducted under both microwave irradiation and conventional heating conditions. Acetylferrocene and acetophenone were subjected to oximation under the two conditions in various solvent mixtures, and the extent of conversion was determined by 1H nuclear magnetic resonance spectroscopy. Microwave irradiation was found to accelerate the rate of oximation of both acetylferrocene and acetophenone. Acceleration of the reaction under microwave irradiation was attributed to the efficient absorption of microwaves by the ferrocene nucleus.
Nurudeen Ishola Mohammed, Nassereldeen Ahmed Kabbashi, Zahangir Alam, Mohamed Elwathig S. Mirghani
Green and Sustainable Chemistry, Volume 11, pp 23-37; doi:10.4236/gsc.2021.111003

Abstract:
Cost of biodiesel is primarily because of factors such as the feedstock, production process and materials. Apparently, the final biodiesel product is a bit expensive compared to fossil diesel fuel. While non-food feedstock of high oil content such as Jatropha curcas has been proposed to reduce the cost due to the feedstock, a promising two-step approach of hydro-esterification can possibly offset the production cost for oil resource with high free fatty acids. Most importantly, optimization of the materials and process is expected to reduce wastage, enhance product purity and generate less wastewater. However, optimizing product generation has been dauntingly elusive because several parameters are needed to be considered holistically. In this study, Response Surface Methodology (RSM) was employed to optimize the yield and conversion of Jatropha biodiesel from J. curcas hydrolysate. An optimum Yield and conversion of 96% was achieved for both responses with an optimum temperature value of 60°C, 4 wt% for catalyst loading for 6 hrs reaction time. Findings imply that optimization study of Jatropha curcas hydrolysate for yield and conversion of fatty acid methyl esters using face centered central composite design of Design Expert 6.0.8 can ensure purity of product, conserve energy and reduce waste generation providing a significant frontier in biodiesel pricing.
Sujata Mandal, Sreekar B. Marpu, Roxana Hughes, Mohammad A. Omary, Sheldon Q. Shi
Green and Sustainable Chemistry, Volume 11, pp 28-38; doi:10.4236/gsc.2021.111004

Abstract:
A procedure for the green synthesis of silver nanoparticles (AgNPs) using Cannabis sativa (hemp plant) as a stabilizing media was developed and antibacterial activity was tested. Within 30 minutes of heating the mixture of silver nitrate and hemp extract, the formation of silver nanoparticles took place under the complete absence of a chemical reducing or an additional stabilizing agent. The so-formed AgNPs were characterized using different optical spectroscopy and electron microscopy techniques. The initial formation of AgNPs was established from UV-Vis data based on surface plasmon resonance (SPR) of AgNPs at ~417 nm. The exact size, shape, and elemental composition of AgNPs were established from ESEM images and EDS data. The antibacterial activity of these nanoparticles was studied on Gram-positive Staphylococcus aureus, and Gram-negative Escherichia coli following Disk diffusion and Minimum Inhibitory Concentration (MIC) tests. Results showed that the biosynthesis of silver nanoparticles using hemp extract could be a simple,inexpensive, and biocompatible method.
Helen Olayinka Ogunsuyi, Christiana Aanu Olawale
Green and Sustainable Chemistry, Volume 11, pp 59-71; doi:10.4236/gsc.2021.112006

Abstract:
This study investigated the viability of post-harvested plantain biomass as a promising feedstock for the production of Bioethanol. The properties of the derived bio-ethanol were determined to examine its suitability as a promising and sustainable alternative to petroleum-based ethanol The research revealed that Plantain biomass is made up of Lignocellulosic contents such as extractive, Lignin, cellulose, hemicelluloses, ash and moisture in different proportions. The different parts of the biomass such as the flower, stem and leaves were hydrolyzed using H2SO4. Optimum hydrolysis conditions of 6%w/v acid concentration, 30 min contact time and 80°C working temperature were established for Plantain stem and flower. However, hydrolysis of Plantain leaves was at the best under the experimental conditions of acid concentration (10% w/v), contact time (120 min) and temperature (120°C). The highest yield of the bio-ethanol produced was obtained from Plantain stem biomass with a record of 8.04% followed by Plantain flower with a yield of 7.73% and 757% from Plantain leaves The hydrolyzate was fermented using Baker’s yeast (Saccharomyces cerevisiae) at a room temperature of 25°C and pH of 4.5 for 4 D. The structural determination of the derived bioethanol was conducted using FT-IR analysis and the fuel properties were found to be consistent with those of the conventional ethanol. The SEM analysis conducted on the post hydrolysed biomass confirmed the effectiveness of the hydrolysis scheme adopted as evident on the surface morphology of the biomass. This study confirmed the viability of Plantain biomass as promising feedstock for Bio-ethanol production under the established hydrolysis conditions.
Aristide H. W. Nakavoua, Guy Crépin Enoua, Stéphanie Manhan-Iniangas, Pierre Chalard, Gilles Figuérédo
Green and Sustainable Chemistry, Volume 11, pp 49-58; doi:10.4236/gsc.2021.112005

Abstract:
Skin aging is a process most often attributed to UV [1] and also to the use of creams and other cosmetic products low in antioxidant compounds [2]. Photochemically stable pepo Cucurbita oil can be used as an exogenous cosmetic supplement due to its high antioxidant content. Incorporated in an agar, media containing a synthetic melanin solution with added pumpkin oil are subjected to UV light, the aging thus modeled is followed by the measurement of photoresistance values correlated with chemical and spectrophotometric analyses. This study confirms that pumpkin oil is highly effective in protecting the skin, especially the most sensitive skins such as babies’ skin [3] by reinforcing the action of melanin and also that of albinos without melanin. Indeed its SPF (Significant Sun Protection Factor) index estimated during this work is very consistent, i.e. more than 22% of UVB (280 - 315 nm) radiations are suppressed.
Hiromu Okada, Chao Zhao, Yusuke Mizuta, Katsumi Yoshino, Ryuichi Sugimoto
Green and Sustainable Chemistry, Volume 11, pp 9-22; doi:10.4236/gsc.2021.111002

Abstract:
Methyl methacrylate (MMA) was successfully grafted onto cellulose nanofibers (CNFs) at room temperature in an emulsion system using a diethyl(1,10-phenanthroline N1,N10)zinc(II) complex (Phen-DEZ) with oxygen as the radical initiator. The effects of reaction temperature, initiator concentration, and monomer content on the grafting reaction were investigated. The molecular weight of the non-grafted PMMA, which was produced during graft polymerization, was more than 1 million, as determined by size exclusion chromatography. The PMMA-grafted CNFs were analyzed by Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy, which confirmed the grafting of PMMA on the nanofiber surface. The study presents a strategy for the grafting of high-molecular weight PMMA onto CNFs in an emulsion system using Phen-DEZ and O2.
Mohammad A. Aldoasri, Sawsan S. Darwish, Mahmoud A. Adam, Nagib A. Elmarzugi, Sayed M. Ahmed
Green and Sustainable Chemistry, Volume 10, pp 72-90; doi:10.4236/gsc.2020.103006

Abstract:
This part of study represents the applied study; which is a continuation of the experimental study that was carried out in part 1 [1]. The experimental study in part 1 focused on evaluation of the effectiveness of Montmorillonite clay, calcium carbonate, and silicon dioxide nanoparticles for enhancing the performances of epoxy adhesives used in re-assembly of archaeological massive limestones. Based on the obtained results in part 1, the choice fell on epoxy-clay nanocomposites as the best re-assembly adhesive material reinforced with Stainless Steel to conduct the applied study project. The current applied study that represents a big project was carried out on 3 archaeological pharaonic massive limestones discovered separately in Ain Shams (Heliopolis) archaeological area in Egypt. The methodology included an accurate archaeological study, followed by analytical, and then the restoration and reassembly process. Firstly; in order to prove whether these artifacts are complementary to each other or not, then with a view to re-assembly and conserving these artifacts in the form of one stone block to be ready for museum display. Referred to the comprehensive archaeological and analytical study of the mentioned archeological stones, the results confirmed that, these stone pieces, in the original were one piece, therefore, it is possible to regrouping again to become one block complementary to each other, and this is what was done in this study.
Alang Michael Bong, Ndikontar Maurice Kor, Peter T. Ndifon
Green and Sustainable Chemistry, Volume 10, pp 57-71; doi:10.4236/gsc.2020.103005

Abstract:
This paper reports a field survey undertaken to determine the availability of raw material for palm kernel oil commercial production for industrial applications. Both industrial and artisanal wastes from palm kernel oil production were also surveyed as raw material (palm kernel seeds) for green energy production. Results of the field study show that 22% of palm kernel seeds (which represents tons of waste) resulting from palm oil processing plants are dumped while at the artisanal level, 80% of palm kernel seed waste is dumped. Analysis of field study data shows that large amounts of waste palm kernel seeds are available to enable large scale production of palm kernel oil (PKO) for desirable industrial applications in green energy production. The paper also reports on the physical and chemical properties of Cameroon palm kernel oil (PKO). Palm kernel oil was extracted using mechanical press and solvent extraction. The palm kernel oil (PKO) from Cameroon was analyzed by standard physico-chemical methods. Results of the physical measurements show a specific gravity of PKO of 0.92 kg/L, viscosity of 26.03 cSt and at 5.93 cSt at 40°C and 100°C respectively, viscosity index of 185, pour point of 20°C, cloud point of 29°C, flash point of 200°C, aniline point of 105°F, diesel index of 23, cetane number of 27 and ASTM (American Standards for Testing and Materials) color of less than 2.5. Results of chemical analyses showed an acid value of 17.95 mg KOH/g, free fatty acid (FFA) content of 8.98 mg KOH/g, iodine value of 2.10 mg I2/g, peroxide value of 2.10 meq/kg, ester value of 123.0 mg KOH/g, hydroxyl value of 93.4 mg OH/g, saponification value of 140.95 mg KOH/g and a sulfur content of 0.016% w/v, signifying low sulfur content. Gas chromatography-mass spectrometry (GC-MS) showed the palm kernel oil to be predominantly made up of glycerides of various fatty acids with higher proportions of C12 to C16 fatty acid residues. Cameroon PKO therefore has a broad spectrum of industrial applications by virtue of its rich physical and chemical properties.
Shoko Suzuki, Hiroyuki Ito, Motoyoshi Noike, Shinji Ishizuka, Risehiro Nonaka, Kenji Funaki, Takeshi Kodama, Shujiro Sakaki, Tomomichi Nishino, Mina Ito, et al.
Green and Sustainable Chemistry, Volume 10, pp 1-17; doi:10.4236/gsc.2020.101001

Abstract:
Recently, the development of environmentally friendly syntheses of imine derivatives, which were attracting great attention for their reactivity and structure in various fields, progressed rapidly because the concept of green chemistry had deeply penetrated into society. In our previous work, we had reported new synthetic methods of imine derivatives using some active amines under solvent- and catalyst-free reaction conditions. This synthetic reaction proceeded smoothly and target compounds were obtained in excellent yields. In this system, when less reactive amines were used as substrates, the synthetic reaction was not finished in the short reaction time, and the corresponding compounds were given in moderate yields. In order to solve this point, we tried to improve the reaction conditions of this method. Through this improvement, it was found that pure target compounds could be obtained in excellent yields by using 1.1 equivalents of less reactive amines to aldehydes and extending the reaction time compared with our previous work. In this paper, we will introduce the detail of this study, and also report the result of the investigation of the reaction property by computational chemistry.
Mohammad A. Aldosari, Sawsan S. Darwish, Mahmoud A. Adam, Nagib A. Elmarzugi, Sayed M. Ahmed
Green and Sustainable Chemistry, Volume 10, pp 24-38; doi:10.4236/gsc.2020.101003

Abstract:
Massive limestones were used in construction of ancient Egyptian tombs, temples, obelisks and other sculptures. These stones are always exposed to physico-mechanical deterioration and destructive forces, leading to partial or total collapse. The task of reassembling this type of artifacts represents a big challenge for the conservators. Recently, the researchers are turning to new technologies to improve the properties of traditional adhesive materials and techniques used in re-assembly of broken massive stones. The epoxy resins are used extensively in stone conservation and re-assembly of broken stones because of their outstanding mechanical properties. The adding of nanoparticles to polymeric adhesives at low percentages may lead to substantial improvements of their mechanical performances in structural joints and massive objects. The aim of this study is to evaluate the effectiveness of montmorillonite clay, calcium carbonate, and silicon dioxide nanoparticles for enhancing the performances of epoxy adhesives used in re-assembly of archaeological massive limestones. Scanning electron microscopy (SEM) was employed in order to investigate the morphology of the prepared nanocomposites, and the distribution of nanoparticles inside the composites. Artificial aging, tensile, compressive, and elongation strength tests were used to evaluate the efficiency of epoxy-nanocomposites. The results showed that the epoxy-clay nanocomposites exhibited superior tensile, compressive, and elongation strength, in addition to improving the mechanical properties of stone joints.
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