scholarly journals Self-Stabilized Precipitation Polymerization and Its Application

Research ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Zhenjie Liu ◽  
Dong Chen ◽  
Jinfang Zhang ◽  
Haodong Liao ◽  
Yanzhao Chen ◽  
...  
Keyword(s):  
Polymeric Nanoparticles ◽  
Reaction Medium ◽  
Value Added ◽  
Nucleation And Growth ◽  
Huge Amount ◽  
Uniform Size ◽  
Synthetic Strategy ◽  
Heterogeneous Polymerization ◽  
Supernatant Liquid ◽  
Polymerization Method

An effective, value-added use of the large amounts of olefinic compounds produced in the processing of petroleum, aside from ethylene and propylene, has been a long outstanding challenge. Here, we developed a novel heterogeneous polymerization method, beyond emulsion/dispersion/suspension, termed self-stabilized precipitation (2SP) polymerization, which involves the nucleation and growth of nanoparticles (NPs) of a well-defined size without the use of any stabilizers and multifunctional monomers (crosslinker). This technique leads to two revolutionary advances: (1) the generation of functional copolymer particles from single olefinic monomer or complex olefinic mixtures (including C4/C5/C9 fractions) in large quantities, which open a new way to transform huge amount of unused olefinic compounds in C4/C5/C9 fractions into valuable copolymers, and (2) the resultant polymeric NPs possess a self-limiting size and narrow size distribution, therefore being one of the most simple, efficient, and green strategies to produce uniform, size-tunable, and functional polymeric nanoparticles. More importantly, the separation of the NPs from the reaction medium is simple and the supernatant liquid can be reused; hence this new synthetic strategy has great potential for industrial production.

scholarly journals Optimization of Synthetic Media Composition for Kluyveromyces marxianus Fed-Batch Cultivation

Fermentation ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 62
Author(s):  
Konstantins Dubencovs ◽  
Janis Liepins ◽  
Arturs Suleiko ◽  
Anastasija Suleiko ◽  
Reinis Vangravs ◽  
...  
Keyword(s):  
Kluyveromyces Marxianus ◽  
Reaction Medium ◽  
Value Added ◽  
Batch Cultivation ◽  
Batch Processes ◽  
Biomass Growth ◽  
High Cell ◽  
Media Composition ◽  
Fed Batch ◽  
Fed Batch Cultivation

The Kluyveromyces marxianus yeast recently has gained considerable attention due to its applicability in high-value-added product manufacturing. In order to intensify the biosynthesis rate of a target product, reaching high biomass concentrations in the reaction medium is mandatory. Fed-batch processes are an attractive and efficient way how to achieve high cell densities. However, depending on the physiology of the particular microbial strain, an optimal media composition should be used to avoid by-product synthesis and, subsequently, a decrease in overall process effi-ciency. Thus, the aim of the present study was to optimise the synthetic growth medium and feeding solution compositions (in terms of carbon, nitrogen, phosphorous, magnesium, and calcium concentrations) for high cell density K. marxianus fed‑batch cultivations. Additionally, the biomass yields from the vitamin mixture and other macro/microelements were identified. A model predictive control algorithm was successfully applied for a fed-batch cultivation control. Biomass growth and substrate consumption kinetics were compared with the mathematical model predictions. Finally, 2‑phenylethanol biosynthesis was induced and its productivity was estimated. The determined optimal macronutrient ratio for K. marxianus biomass growth was identified as C:N:P = 1:0.07:0.011. The maximal attained yeast biomass concentration was close to 70 g·L-1 and the 2-PE biosynthesis rate was 0.372 g·L−1·h−1, with a yield of 74% from 2-phenylalanine.

Combinatorial synthesis of soluble conjugated polymeric nanoparticles and tunable multicolour fluorescence sensing

2017 ◽  
Vol 8 (37) ◽  
pp. 5734-5740 ◽  
Author(s):  
Peng Zhao ◽  
Yanan Dai ◽  
Yusen Wu ◽  
Lili Wang ◽  
Binlei Huang ◽  
...  
Keyword(s):  
Polymeric Nanoparticles ◽  
Combinatorial Synthesis ◽  
Fluorescence Sensing ◽  
Polymerization Method

Combinatorial polymerization method has been exploited to prepare a library of soluble conjugated polymeric nanoparticles (SCPNs), by varying symmetrical monomers, Ax and By (x > 2, y ≥ 2), plus modification with variant terminal groups.

Study on the Synthesis of Carboxymethylpachyman in the Aqueous-Ethanol Medium with the Assistance of Ultrasonics

2011 ◽  
Vol 236-238 ◽  
pp. 2810-2814
Author(s):  
Yong Jiang Wang ◽  
Xue Qian Wu ◽  
Shi Wang Liu ◽  
Yuan Feng Wu ◽  
Yan Ping Zhang
Keyword(s):  
Biological Activity ◽  
Aqueous Ethanol ◽  
Reaction Medium ◽  
Volume Ratio ◽  
Value Added ◽  
Poria Cocos ◽  
A Value ◽  
Ethanol Medium ◽  
Favorable Conditions ◽  
Carboxymethyl Pachyman

Water-insoluble β - ( 1 - 3 ) – D - glucan isolated from the sclerotium of Poria cocos hardly exhibits biological activity. Therefore, it is advantageous to produce a value-added product from Poria cocos. We extracted the β - ( 1 - 3 ) – D - glucan from the sclerotium of Poria cocos and synthesized a carboxymethylated derivative, carboxymethyl-pachyman (CMP). The influences on the degrees of substitution ( DS ) of CMP, for example, volume ratio of ethanol to water, [NaOH]/[MCA] ratio, reaction temperature and reaction time have been examined, respectively. The most favorable conditions for pachyman carboxymethylation are obtained with a [NaOH]/[MCA] ratio of 1.5, at 45°C for 60 minutes with a reaction medium consisting of a ethanol/water 80:20 (v/v) mixture.

scholarly journals Cochineal Waxy Residues as Source of Policosanol: Chemical Hydrolysis and Enzymatic Transesterification

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Emilia Ramos-Zambrano ◽  
Pedro Herrera-Serrano ◽  
Jorge García-Dávila ◽  
Gabriel Ríos-Cortés ◽  
Antonio Ruperto Jiménez-Aparicio ◽  
...  
Keyword(s):  
Molecular Sieves ◽  
Reaction Medium ◽  
Value Added ◽  
Carminic Acid ◽  
Enzymatic Transesterification ◽  
Chemical Hydrolysis ◽  
Agroindustrial Waste ◽  
Main Component ◽  
Long Chain ◽  
Value Added Products

The aim of this study was to obtain and characterise the long-chain alcohols present in policosanol derived from waste from the production of carminic acid, a natural colouring agent widely used in the food industry. The effectiveness of different methods designed for extraction of policosanol from waxy waste was investigated and its content and composition was determined. Triacontanol was the main component in policosanol produced by chemical processes, and it yields up to 13% by alkaline hydrolysis in water and chloroform extraction. Regarding enzymatic transesterification, policosanol was obtained using lipase Candida antarctica recombinant in Aspergillus niger (CAL-Bn) in a reaction medium with toluene. To improve the reaction, different acyl receptors, propanol, butanol, and isopropanol, were tested and molecular sieves were employed to maintain an anhydrous reaction medium. In this case, the policosanol was made up of other long-chain alcohols, but triacontanol was obtained in yields of up to 19% using isopropanol as an acyl receptor. Triacontanol has a great commercial value due to its effect as a promoter of plant growth, and these results contribute to the use and application of this agroindustrial waste in obtaining value-added products.

scholarly journals Phase-Selective Microwave Assisted Synthesis of Iron(III) Aminoterephthalate MOFs

Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1469 ◽  
Author(s):  
Ana Arenas-Vivo ◽  
David Avila ◽  
Patricia Horcajada
Keyword(s):  
Reaction Medium ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
Synthetic Strategy ◽  
Transmission Electron ◽  
Metal Organic ◽  
High Space ◽  
Pure Phases ◽  
The Impact ◽  
Reaction Media

Iron(III) aminoterephthalate Metal-Organic Frameworks (Fe-BDC-NH2 MOFs) have been demonstrated to show potential for relevant industrial and societal applications (i.e., catalysis, drug delivery, gas sorption). Nevertheless, further analysis is required in order to achieve their commercial production. In this work, a systematic synthetic strategy has been followed, carrying out microwave (MW) assisted hydro/solvothermal reactions to rapidly evaluate the influence of different reaction parameters (e.g., time, temperature, concentration, reaction media) on the formation of the benchmarked MIL-101-NH2, MIL-88B-NH2, MIL-53-NH2 and MIL-68-NH2 solids. Characterization of the obtained solids by powder X-ray diffraction, dynamic light scattering and transmission electron microscopy allowed us to identify trends to the contribution of the evaluated parameters, such as the relevance of the concentration of precursors and the impact of the reaction medium on phase crystallization. Furthermore, we presented here for the first time the MW assisted synthesis of MIL-53-NH2 in water. In addition, pure MIL-101-NH2 was also produced in water while MIL-88-NH2 was the predominant phase obtained in ethanol. Pure phases were produced with high space-time yields, unveiling the potential of MW synthesis for MOF industrialization.

Synthesis and grafting of carboxymethyl cellulose from environmental pollutant cellulosic wastes of textile industry

2016 ◽  
Vol 20 (3) ◽  
pp. 126-135 ◽  
Author(s):  
Md. Ibrahim H. Mondal ◽  
Firoz Ahmed
Keyword(s):  
Methyl Methacrylate ◽  
Carboxymethyl Cellulose ◽  
Reaction Medium ◽  
Value Added ◽  
Single Step ◽  
Cellulose Derivatives ◽  
Content Type ◽  
Cellulosic Waste ◽  
Methacrylate Monomer ◽  
Methyl Methacrylate Monomer

Purpose This study aims to explore the use of knitted rag by synthesizing different grades of carboxymethyl cellulose (CMC) by applying multiple-step carboxymethylation techniques. Design/methodology/approach CMC was synthesized from knitted rag, a cellulosic waste of textile and garment industries, in aqueous ethanolic sodium hydroxide and subsequently mono-chloroacetic acid reaction medium. Low-substituted to high-substituted products were obtained from single-step to seven-step carboxymethylation of cellulose. In this way, it was possible to produce low-cost and different grades of substituted carboxymethylated cellulose. The synthesized CMC was characterized, and their physical properties were investigated. The structure of CMC and grafted CMC were investigated by Fourier transform infrared spectroscopy. Findings Solubility, CMC content, degree of substitution and molecular weight of CMC were increased gradually with the increase in the number of reaction steps, although fourth step attained the optimum. The cellulosic waste of knitted rag can easily be used to produce value-added products such as CMC and other cellulose derivatives, and that will ultimately reduce the pollution problems from this waste. Originality/value Grafting of prepared CMC film with methyl methacrylate monomer increased their strength, although decreased rigidity and moisture content because the incorporation of hydrophobic methyl methacrylate monomer was observed.

scholarly journals Sugarcane Bagasse Hydrolysis Enhancement by Microwave-Assisted Sulfolane Pretreatment

Energies ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1703 ◽  
Author(s):  
Patricia Portero-Barahona ◽  
Enrique Javier Carvajal-Barriga ◽  
Jesús Martín-Gil ◽  
Pablo Martín-Ramos
Keyword(s):  
Reaction Time ◽  
Sugarcane Bagasse ◽  
Energy Savings ◽  
Enzymatic Saccharification ◽  
Reaction Medium ◽  
Value Added ◽  
Positive Influence ◽  
Industrial Applications ◽  
Combined Pretreatment ◽  
Total Reducing Sugars

Sugarcane bagasse is the major by-product of the sugarcane industry and, due to its abundant availability, it has been extensively studied for lignocellulosic bioconversion in the production of bioethanol and other value-added commercial products. In the study presented herein, a combined pretreatment using sulfolane, TiO2 and alkali microwave irradiation (MW-A) was assessed for the dissolution of lignin prior to enzymatic saccharification of holocellulose. Total reducing sugars (TRS) and saccharinic acid yields were investigated. The increase in NaOH concentration up to 5% and in temperature from 120 °C to 140 °C were found to have a positive influence on both yields. While increasing the reaction time from 5 to 60 min only led to an increase in TRS yield <2%, a reaction time of 30 min almost doubled the saccharinic acids production. TRS yields and saccharinic acid production were approximately 5% and 33% higher when the sulfolane-TiO2 reaction medium was used, as compared to MW-A in water, reaching up to 64.8% and 15.24 g/L of saccharinic acids, respectively. The proposed MW-A pretreatment may hold promise for industrial applications, given the good TRS yields obtained, and the associated enzyme and time/energy savings. The use of sulfolane-TiO2 reaction medium is encouraged if saccharinic acids are to be recovered too.

Rod-Like Rutile Nanoparticles: Synthesis, Structure and Morphology

2017 ◽  
Vol 50 ◽  
pp. 32-40 ◽  
Author(s):  
Volodymyr Kotsyubynsky ◽  
Ivan Myronyuk ◽  
Volodymyr Chelyadyn ◽  
Andrii Hrubiak ◽  
Volodymyr Moklyak ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Hydrochloric Acid ◽  
Specific Surface ◽  
Reaction Medium ◽  
Nucleation And Growth ◽  
Molar Ratio ◽  
Structure And Morphology ◽  
Nanoparticles Synthesis ◽  
Preferred Oriented ◽  
Hydrolysis Of

Nanodispersed rutile with rod-like particles is synthesized by hydrolysis of TiCl4 in hydrochloric acid - ethanol alcohol aqueous solution. It is found that the specific surface area, crystallite size and degree of agglomeration are determined by molar ratio of ethanol in reaction medium. According to HR-TEM images and XRD data rutile crystallites are preferred oriented along the [001] axis. The analysis of the Raman spectra for samples with different morphology is performed. The model of rutile nanorods nucleation and growth is proposed.

Value-Added Processing of Lactose: Preparation of Bioactive Lactobionic Acid Using a Novel Catalytic Method

2007 ◽  
Vol 5 (1) ◽  
Author(s):  
Khaled Belkacemi ◽  
Mirela Cristea Vlad ◽  
Safia Hamoudi ◽  
Joseph Arul
Keyword(s):  
Active Sites ◽  
Bimetallic Catalyst ◽  
Batch Reactor ◽  
Reaction Medium ◽  
Value Added ◽  
Operating Conditions ◽  
Molar Ratio ◽  
Catalytic Method ◽  
Metals Loading ◽  
Ph Range

The microaerial oxidation of an aqueous solution of lactose to lactonionic acid (LBA) over the heterogeneous bimetallic catalyst Bi-Pd supported on mesoporous SBA-15 material was carried out in an agitated semi-batch reactor in alkaline medium within the pH range of 7 to 9.The present work focused on the synthesis and characterization of the bimetallic catalyst as well as optimization of the reaction operating conditions. To this purpose, the effect of both active metals loading on the support, metal/lactose ratio, reaction pH and dissolved oxygen concentration on the oxidation performances was examined at a very mild temperature of 65 oC.The bimetallic catalyst 1.02%Pd, 0.64%Bi/SBA-15, (Bi/Pd molar ratio of 0.3) showed the highest activity (96 % lactose conversion) and 100 % selectivity towards the targeted LBA product. Furthermore, the formulated catalyst proved to be stable in the reaction medium as both metals leaching was insignificant. Based on XRD and XPS analyses, it is suggested that the metals constituting the bimetallic catalyst active sites assemble into an intermetallic alloy having Bi1.75Pd stoichiometry.

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