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Chitosan/polyethylene glycol impregnated activated carbons: Synthesis, characterization and adsorption

Ehsan Salehi, Fereshteh Soroush, Maryam Momeni, Aboulfazl Barati, Ali Khakpour

《化学科学与工程前沿（英文）》 2017年 第11卷 第4期   页码 575-585 doi: 10.1007/s11705-017-1650-2

摘要： Novel modified activated carbons (ACs) with enhanced adsorptive properties were obtained coating by chitosan (CS), polyethylene glycol (PEG) and blends of the two polymers (0:1, 1:0, 1:1, 1:2 and 2:1 wt/wt) on ACs by an impregnation technique. The adsorption performances of the pristine, acidified and polymer-impregnated ACs were studied using methylene blue as a model adsorbate. The adsorbents were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy and abrasion hardness tests. The average coating thicknesses were between 10 to 23 microns. The pore sizes, pore densities and pore capacities of the activated carbons increased as the wt-% PEG in the coating increased. The highest adsorption capacity (424.7 mg/g) was obtained for the chitosan-coated ACs and this adsorption was well described by the Langmuir isotherm model. The kinetic results were best described by the pseudo-second-order kinetic model. The highest rate constant was obtained with the ACs modified with the CS:PEG (2:1) coating and this result was almost 2.6 times greater than that of the unmodified ACs. The CS/PEG impregnated ACs also displayed superior hardness (~90%), compared to unmodified ACs (~85%). Overall the chitosan had a greater effect on improving adsorption capacity whereas the polyethylene glycol enhanced the adsorption rate.

关键词： carbon biocomposites     impregnation     chitosan     polyethylene glycol     image processing    

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Encapsulation of polyethylene glycol in cellulose-based porous capsules for latent heat storage and light-to-thermal

《化学科学与工程前沿（英文）》 2023年 第17卷 第8期   页码 1038-1050 doi: 10.1007/s11705-022-2279-3

摘要： Phase change materials are potential candidates for the application of latent heat storage. Herein, we fabricated porous capsules as shape-stable materials from cellulose-based polyelectrolyte complex, which were first prepared using cellulose 6-(N-pyridinium)hexanoyl ester as the cationic polyelectrolyte and carboxymethyl cellulose as the anionic polyelectrolyte to encapsulate polyethylene glycol by the vacuum impregnation method. Furthermore, the multi-walled carbon nanotube or graphene oxide, which were separately composited into the polyelectrolytes complex capsules to enhance thermal conductivity and light-to-thermal conversion efficiency. These capsules owned a typical core–shell structure, with an extremely high polyethylene glycol loading up to 34.33 g∙g‒1. After loading of polyethylene glycol, the resulted cellulose-based composite phase change materials exhibited high thermal energy storage ability with the latent heat up to 142.2 J∙g‒1, which was 98.5% of pure polyethylene glycol. Further results showed that the composite phase change materials demonstrated good form-stable property and thermal stability. Moreover, studies involving light-to-thermal conversion determined that composite phase change materials exhibited outstanding light-to-thermal conversion performance. Considering their exceptional comprehensive features, innovative composite phase change materials generated from cellulose presented a highly interesting choice for thermal management and renewable thermal energy storage.

关键词： cellulose     polyelectrolytes     phase change materials     thermal energy storage     light-to-thermal conversion    

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Effects of a dynamic membrane formed with polyethylene glycol on the ultrafiltration of natural organic

Boksoon KWON, Noeon PARK, Jaeweon CHO,

《环境科学与工程前沿（英文）》 2010年 第4卷 第2期   页码 172-182 doi: 10.1007/s11783-010-0002-y

摘要： The formation of a dynamic membrane (DM) was investigated using polyethylene glycol (PEG) (molecular weight of 35000 g/mol, concentration of 1 g/L). Two natural organic matters (NOM), Dongbok Lake NOM (DLNOM) and Suwannee River NOM (SRNOM) were used in the ultrafiltration experiments along with PEG. To evaluate the effects of the DM with PEG on ultrafiltration, various transport experiments were conducted, and the analyses of the NOM in the membrane feed and permeate were performed using high performance size exclusion chromatography, and the pore size distribution ( PSD) and molecular weight cut off ( MWCO) were determined. The advantages of DM formed with PEG can be summarized as follows: (1) PEG interferes with NOM transmission through the ultrafiltration membrane pores by increasing the retention coefficient of NOM in UF membranes, and (2) low removal of NOM by the DM is affected by external factors, such as pressure increases during UF membrane filtration, which decreases the PSD and MWCO of UF membranes. However, a disadvantage of the DM with PEG was severe flux decline; thus, one must be mindful of both the positive and negative influences of the DM when optimizing the UF performance of the membrane.

关键词： dynamic membrane     natural organic matters     ultrafiltration membrane performance     effective PSD     effective molecular weight cutoff    

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Effect of polyethylene glycol on the crystallization, rheology and foamability of poly(lactic acid) containing

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 2074-2087 doi: 10.1007/s11705-023-2342-8

摘要： In this study, the rheological properties, crystallization and foaming behavior of poly(lactic acid) with polyamide 6 nanofibrils were examined with polyethylene glycol as a compatibilizer. Polyamide 6 particles were deformed into nanofibrils during drawing. For the 10% polyamide 6 case, polyethylene glycol addition reduced the polyamide 6 fibril diameter from 365.53 to 254.63 nm, owing to the smaller polyamide 6 particle size and enhanced interface adhesion. Rheological experiments revealed that the viscosity and storage modulus of the composites were increased, which was associated with the three-dimensional entangled network of polyamide 6 nanofibrils. The presence of higher aspect ratio polyamide 6 nanofibrils substantially enhanced the melt strength of the composites. The isothermal crystallization kinetics results suggested that the polyamide 6 nanofibrils and polyethylene glycol had a synergistic effect on accelerating poly(lactic acid) crystallization. With the polyethylene glycol, the crystallization half-time reduced from 103.6 to 62.2 s. Batch foaming results indicated that owing to higher cell nucleation efficiency, the existence of polyamide 6 nanofibrils led to a higher cell density and lower expansion ratio. Furthermore, the poly(lactic acid)/polyamide 6 foams exhibited a higher cell density and expansion ratio than that of the foams without polyethylene glycol.

关键词： poly(lactic acid)     foaming     microfibrillation     rheological property     crystallization    

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Polyethylene glycol-supported ionic liquid as a highly efficient catalyst for the synthesis of propylene

Rui YAO, Hua WANG, Jinyu HAN

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 239-245 doi: 10.1007/s11705-012-1297-y

摘要： The coupling reaction of propylene and CO to form propylene carbonate (PC) was promoted by an ionic liquid (IL) covalently bound to polyethylene glycol (PEG). The supported ionic liquid, which has both acidic and basic components, proved to be an active catalyst for PC synthesis under mild conditions. The effects of different cations and anions, reaction temperature, CO pressure, and reaction time were investigated. It was demonstrated that the acid group in the catalyst plays an important role in the reaction. With this system, a high PC yield (95%) was achieved under mild conditions (3.0 MPa, 120°C and 4 h) without a co-solvent. In addition, the catalyst was readily recovered and reused. Based on the experimental results, a plausible mechanism for the catalyst was proposed.

关键词： ionic liquid     PEG-supported ionic liquid     carbon dioxide     propylene carbonate    

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Preparation and characterization of PVDF-PFSA flat sheet ultrafiltration membranes

Jiquan MA, Junhong ZHAO, Zhongbin REN, Lei LI

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 301-310 doi: 10.1007/s11705-012-1204-6

摘要： High performance polyvinylidene fluoride (PVDF) flat sheet ultrafiltration (UF) membranes have been prepared by an immersion precipitation phase inversion method using perfluorosulfonic acid (PFSA) as a pore former and as a hydrophilic component of the membranes and polyethylene glycol ( = 400) (PEG400) as a pore forming agent. The effects of the presence of PEG and the concentration of the PFSA on the phase separation of the casting solutions and on the morphologies and performance of UF membranes including their porosity, water flux, rejection of bovine serum albumin (BSA) protein, and anti-fouling property were investigated. Phase diagrams, viscosities and the phase separations upon exposure to water vapor showed that both PEG400 and PFSA promoted demixing of the casting solution. Scanning electron microscopy measurements showed that the PVDF-PFSA blend membranes had more macropores and finger-like structures than the native PVDF membranes. The PVDF-PFSA membrane (5 wt-% PEG400+ 5 wt-% PFSA) had a pure water flux of 141.7 L/m ·h, a BSA rejection of 90.1% and a relative pure water flux reduction (RFR) of 15.28%. These properties were greatly superior to those of the native PVDF membrane (pure water flux of 5.6 L/m ·h, BSA rejection of 96.3% and RFR of 42.86%).

关键词： polyvinylidene fluoride     perfluorosulfonic acid     polyethylene glycol     flat sheet membrane     ultrafiltration    

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Conversion of polyethylene to gasoline: Influence of porosity and acidity of zeolites

《能源前沿（英文）》   页码 763-774 doi: 10.1007/s11708-023-0897-1

摘要： Plastic waste is causing serious environmental problems. Developing efficient, cheap and stable catalytic routes to convert plastic waste into valuable products is of great importance for sustainable development, but remains to be a challenging task. Zeolites are cheap and stable, but they are usually not efficient for plastic conversion at a low temperature. Herein a series of microporous and mesoporous zeolites were used to study the influence of porosity and acidity of zeolite on catalytic activity for plastics conversion. It was observed that H-Beta zeolite was an efficient catalyst for cracking high-density polyethylene to gasoline at 240 °C, and the products were almost C4–C12 alkanes. The effect of porosity and acidity on catalytic performance of zeolites was evaluated, which clearly visualized the good performance of H-Beta due to high surface area, large channel system, large amount accessible acidic sites. This study provides very useful information for designing zeolites for efficient conversion of plastics.

关键词： plastics conversion     polyethylene     zeolites     acidity     porosity    

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Optimization and simultaneous heat integration design of a coal-based ethylene glycol refining process

《化学科学与工程前沿（英文）》 2023年 第17卷 第9期   页码 1280-1288 doi: 10.1007/s11705-023-2301-4

摘要： Coal to ethylene glycol still lacks algorithm optimization achievements for distillation sequencing due to high-dimension and strong nonconvexity characteristics, although there are numerous reports on horizontal comparisons and process revamping. This scenario triggers the navigation in this paper into the simultaneous optimization of parameters and heat integration of the coal to ethylene glycol distillation scheme and double-effect superstructure by the self-adapting dynamic differential evolution algorithm. To mitigate the influence of the strong nonconvexity, a redistribution strategy is adopted that forcibly expands the population search domain by exerting external influence and then shrinks it again to judge the global optimal solution. After two redistributive operations under the parallel framework, the total annual cost and CO2 emissions are 0.61%/1.85% better for the optimized process and 3.74%/14.84% better for the superstructure than the sequential optimization. However, the thermodynamic efficiency of sequential optimization is 11.63% and 10.34% higher than that of simultaneous optimization. This study discloses the unexpected great energy-saving potential for the coal to ethylene glycol process that has long been unknown, as well as the strong ability of the self-adapting dynamic differential evolution algorithm to optimize processes described by the high-dimensional mathematical model.

关键词： ethylene glycol     redistribution     heat integration     optimization     parallel framework    

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聚乙烯类废塑料制聚乙烯蜡技术进展

王璇,冀星,李术元

《中国工程科学》 2001年 第3卷 第12期   页码 90-95

摘要：

废旧塑料的回收利用是近年来治理环境污染的一个重要课题。废聚乙烯（PE）在塑料垃圾中占有很大的比例，如何对其进行合理的回收、利用已成为人们十分关心的问题。从理论和经济两方面分析了废聚乙烯裂解制取聚乙烯蜡技术的可行性，介绍了聚乙烯蜡的性能及市场情况，分析比较了几种有代表性的制蜡工艺，综合评价了这些工艺技术的应用范围和优缺点。还简要介绍了红外脱油技术，并对该技术的研究和应用方向提出了一些建议。

关键词： 聚乙烯类废塑料     热解     聚乙烯蜡    

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Investigating peak stresses in fitting and repair patches of buried polyethylene gas pipes

Reza KHADEMI ZAHEDI, Pouyan ALIMOURI, Hooman KHADEMI ZAHEDI, Mohammad SHISHESAZ

《结构与土木工程前沿（英文）》 2020年 第14卷 第1期   页码 147-168 doi: 10.1007/s11709-019-0587-6

摘要： Nowadays, polyethylene composes a large number of natural gas distribution pipelines installed under the ground. The focus of the present contribution is two fold. One of the objectives is to investigate the applicability of polyethylene fittings in joining polyethylene gas pipes which are electrofused onto the pipe ends and buried under the ground, by estimating stress distribution using finite element method. The second objective is to study the effectiveness of polyethylene repair patches which are used to mend the defected pipelines by performing a finite element analysis to calculate peak stress values. Buried polyethylene pipelines in the natural gas industry, can be imposed by sever loadings including the soil-structure interaction, traffic load, soil’s column weight, internal pressure, and thermal loads resulting from daily and/or seasonal temperature changes. Additionally, due to the application of pipe joints, and repair patches local stresses superimposed on the aforementioned loading effects. The pipe is assumed to be made of PE80 resin and its jointing socket, and the repair patch is PE100 material. The computational analysis of stresses and the computer simulations are performed using ANSYS commercial software. According to the results, the peak stress values take place in the middle of the fitting and at its internal surface. The maximum stress values in fitting and pipe are below the allowable stresses which shows the proper use of introduced fitting is applicable even in hot climate areas of Ahvaz, Iran. Although the buried pipe is imposed to the maximum values of stresses, the PE100 socket is more sensitive to a temperature drop. Furthermore, all four studied patch arrangements show significant reinforcing effects on the defected section of the buried PE gas pipe to transfer applied loads. Meanwhile, the defected buried medium density polyethylene gas pipe and its saddle fused patch can resist the imposed mechanical and thermal loads of 22°C temperature increase. Moreover, increasing the saddle fusion patch length to 12 inches reduces the maximum stress values in the pipe, significantly.

关键词： Ansys software     polyethylene     buried pipelines     polyethylene joints     polyethylene patches     peak von Mises stress     soil-pipe interaction     temperature variation    

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Modification of polycarbonateurethane surface with poly(ethylene glycol) monoacrylate and phosphorylcholine

Jing YANG,Juan LV,Bin GAO,Li ZHANG,Dazhi YANG,Changcan SHI,Jintang GUO,Wenzhong LI,Yakai FENG

《化学科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 188-196 doi: 10.1007/s11705-014-1414-1

摘要： Poly(ethylene glycol) monoacrylate (PEGMA) is grafted onto polycarbonateurethane (PCU) surface via ultraviolet initiated photopolymerization. The hydroxyl groups of poly(PEGMA) on the surface react with one NCO group of isophorone diisocyanate (IPDI) and another NCO group of IPDI is then hydrolyzed to form amino terminal group, which is further grafted with phosphorylcholine glyceraldehyde to establish a biocompatible hydrophilic structure on the surface. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirm the successful grafting of both PEG and phosphorylcholine functional groups on the surface. The decrease of the water contact angle for the modified film is caused by synergic effect of PEG and phosphorylcholine, which both have the high hydrophilicity. Furthermore, the number of platelets adhered is relative low on the synergetically modified PCU film compared with the PCU film modified only by poly(PEGMA). Our synergic modification method using both PEG and phosphorylcholine may be applied in surface modification of blood-contacting biomaterials and some relevant devices.

关键词： poly(ethylene glycol) monoacrylate     phosphorylcholine     polycarbonateurethane     surface modification     anti-platelet adhesion     biomaterials    

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terephthalate)/ethylene propylene diene monomer copolymer grafted with maleic anhydride/metallocene polyethylene

RUN Mingtao, SONG Hongzan, WANG Yingjin, YAO Chenguang, GAO Jungang

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 238-245 doi: 10.1007/s11705-007-0043-3

摘要： The rheological, phase morphologic, thermal and mechanical properties of poly(trimethylene terephthalate)/metallocene polyethylene (PTT/mPE) blends in the presence of ethylene propylene diene monomer copolymer grafted with maleic anhydride (EPDM--MAH) as compatibilizer are studied by means of a capillary rheometer, scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetric analyzer (TGA). Results suggest that the compatibility of PTT/mPE blends is improved greatly after the addition of a compatibilizer. The radius of the dispersed phase in the system decreases greatly when the compatibilizer is added into the blend. When the amount of compatibilizer exceeds 8 wt-%, the size of dispersed phase becomes larger again. This phenomena could be attributed to the higher viscosity of the EPDM--MAH phase, which is dispersed more difficulty in the PTT phase of lower viscosity, thus the mixing efficiency is apparently decreased during the melt blending process. Moreover, the melt viscosity of the blend reaches the maximal value in case of 4 wt-% compatibilizer content, above which it would decrease again. This result is associated with the generation of more and bigger dispersed phase inside the bulk phase, thus the grafting efficiency at the interface is decreased, which could result in lower viscosity. The DSC results suggest that the mPE component shows a nucleating effect, and could increase the overall degree and rate of PTT crystallization, while the addition of a compatibilizer might slightly diminish these effects. In addition, the blend with 4 wt-% compatibilizer shows the best thermal stability. Furthermore, the Izod impact strength and the tensile strength at room temperature of the blend are also markedly improved by the addition of a 4 8 wt-% compatibilizer.

关键词： /metallocene polyethylene     presence     rheological     phenomena     trimethylene terephthalate    

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A review of nondestructive examination technology for polyethylene pipe in nuclear power plant

Jinyang ZHENG, Yue ZHANG, Dongsheng HOU, Yinkang QIN, Weican GUO, Chuck ZHANG, Jianfeng SHI

《机械工程前沿（英文）》 2018年 第13卷 第4期   页码 535-545 doi: 10.1007/s11465-018-0515-9

摘要：

Polyethylene (PE) pipe, particularly high-density polyethylene (HDPE) pipe, has been successfully utilized to transport cooling water for both non-safety- and safety-related applications in nuclear power plant (NPP). Though ASME Code Case N755, which is the first code case related to NPP HDPE pipe, requires a thorough nondestructive examination (NDE) of HDPE joints. However, no executable regulations presently exist because of the lack of a feasible NDE technique for HDPE pipe in NPP. This work presents a review of current developments in NDE technology for both HDPE pipe in NPP with a diameter of less than 400 mm and that of a larger size. For the former category, phased array ultrasonic technique is proven effective for inspecting typical defects in HDPE pipe, and is thus used in Chinese national standards GB/T 29460 and GB/T 29461. A defect-recognition technique is developed based on pattern recognition, and a safety assessment principle is summa-rized from the database of destructive testing. On the other hand, recent research and practical studies reveal that in current ultrasonic-inspection technology, the absence of effective ultrasonic inspection for large size was lack of consideration of the viscoelasticity effect of PE on acoustic wave propagation in current ultrasonic inspection techno-logy. Furthermore, main technical problems were analyzed in the paper to achieve an effective ultrasonic test method in accordance to the safety and efficiency requirements of related regulations and standards. Finally, the development trend and challenges of NDE test technology for HDPE in NPP are discussed.

关键词： polyethylene pipe     nuclear power plant     ultrasonic inspection     nondestructive testing     safety assessment    

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Prediction of high-density polyethylene pyrolysis using kinetic parameters based on thermogravimetric

《环境科学与工程前沿（英文）》 2023年 第17卷 第1期 doi: 10.1007/s11783-023-1606-3

摘要：

● Reducting the sampling frequency can enhance the modelling process.

关键词： HDPE     Pyrolysis     Kinetics     Thermogravimetric     ANOVA     Artificial neural network    

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Augmented hydrogen production by gasification of ball milled polyethylene with Ca(OH)

Giovanni Cagnetta, Kunlun Zhang, Qiwu Zhang, Jun Huang, Gang Yu

《环境科学与工程前沿（英文）》 2019年 第13卷 第1期 doi: 10.1007/s11783-019-1096-5

摘要：

PE ball milling pretreatment induces higher H2 production and purity by gasification.

Ca(OH)2 reacts at solid state with PE boosting H2 and capturing CO2.

Ca(OH)2 significantly reduces methanation side-reaction.

关键词： Hydrogen production     Gasification     Plastic waste     High energy ball milling    

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标题 作者 时间 类型 操作

Chitosan/polyethylene glycol impregnated activated carbons: Synthesis, characterization and adsorption

Ehsan Salehi, Fereshteh Soroush, Maryam Momeni, Aboulfazl Barati, Ali Khakpour

期刊论文

Encapsulation of polyethylene glycol in cellulose-based porous capsules for latent heat storage and light-to-thermal

期刊论文

Effects of a dynamic membrane formed with polyethylene glycol on the ultrafiltration of natural organic

Boksoon KWON, Noeon PARK, Jaeweon CHO,

期刊论文

Effect of polyethylene glycol on the crystallization, rheology and foamability of poly(lactic acid) containing

期刊论文

Polyethylene glycol-supported ionic liquid as a highly efficient catalyst for the synthesis of propylene

Rui YAO, Hua WANG, Jinyu HAN

期刊论文

Preparation and characterization of PVDF-PFSA flat sheet ultrafiltration membranes

Jiquan MA, Junhong ZHAO, Zhongbin REN, Lei LI

期刊论文

Conversion of polyethylene to gasoline: Influence of porosity and acidity of zeolites

期刊论文

Optimization and simultaneous heat integration design of a coal-based ethylene glycol refining process

期刊论文

聚乙烯类废塑料制聚乙烯蜡技术进展

王璇,冀星,李术元

期刊论文

Investigating peak stresses in fitting and repair patches of buried polyethylene gas pipes

Reza KHADEMI ZAHEDI, Pouyan ALIMOURI, Hooman KHADEMI ZAHEDI, Mohammad SHISHESAZ

期刊论文

Modification of polycarbonateurethane surface with poly(ethylene glycol) monoacrylate and phosphorylcholine

Jing YANG,Juan LV,Bin GAO,Li ZHANG,Dazhi YANG,Changcan SHI,Jintang GUO,Wenzhong LI,Yakai FENG

期刊论文

terephthalate)/ethylene propylene diene monomer copolymer grafted with maleic anhydride/metallocene polyethylene

RUN Mingtao, SONG Hongzan, WANG Yingjin, YAO Chenguang, GAO Jungang

期刊论文

A review of nondestructive examination technology for polyethylene pipe in nuclear power plant

Jinyang ZHENG, Yue ZHANG, Dongsheng HOU, Yinkang QIN, Weican GUO, Chuck ZHANG, Jianfeng SHI

期刊论文

Prediction of high-density polyethylene pyrolysis using kinetic parameters based on thermogravimetric

期刊论文

Augmented hydrogen production by gasification of ball milled polyethylene with Ca(OH)

Giovanni Cagnetta, Kunlun Zhang, Qiwu Zhang, Jun Huang, Gang Yu

期刊论文