Assessment of sorption kinetics of carbon nanotube-based composite foams for oil recovery application

Sorption kinetics of pollutant oils, such as kerosene, virgin naphtha, crude oil, and pump oil, into porous siloxanic foams filled with carbon nanotubes (CNTs) are investigated. Both, pristine and functionalized, CNTs are used as foam fillers. Among all, the foam filled with pristine CNT shows a poor affinity with water and high sorption rate in light oils, in which it achieves the highest absorption values (7991 mg g⁻¹ after 660 s and 6685 mg g⁻¹ after 420 s, respectively, in virgin naphtha and kerosene). The kinetic data are described by the pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion models. Results show that chemisorption processes are rate limiting the sorption step. In fact, pseudo-second order model better represents the equilibrium isotherm data. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47374.     

Synthesis of reusable silicone foam containing carbon nanotubes for oil spill remediation

The aim of this work is the synthesis of silicone foam containing carbon nanotubes (CNT) for oil spills remediation. The CNT silicone foams are obtained by foaming a solution of a silicone matrix with CNT filler (5.6 wt %) in presence of a Sn‐based catalyst. Pristine and functionalized CNT have been used. All the obtained materials present a foam morphology with an open cell structure. Each foam is tested in four commonly used oils (kerosene, pump oil, naphtha, and crude oil). Among all, the foam filled with pristine CNT shows the highest sorption capacity (800 wt % in virgin naphtha) and an excellent reusability (up to 10 times). © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46067.     

Open‐cell polypropylene/polyolefin elastomer blend foams fabricated for reusable oil‐sorption materials

The fabrication of high‐performance oil sorbents is of great significance for oil spill cleanup. The main objective of this study was to prepare open‐cell polypropylene/polyolefin elastomer (PP/POE) blend foams for fabrication of reusable sorbents for oil sorption. Open‐cell PP/POE blend foams were prepared via continuous‐extrusion foaming using supercritical carbon dioxide as the blowing agent. The interconnected open‐cell structure was characterized by scanning electron microscopy. The hydrophobicity and lipophilicity of PP/POE open‐cell foams were revealed by tests of contact‐angle measurement, water and cyclohexane sorption on the foam surface, CCl₄ and cyclohexane sorption in water, and oil/water separation. Further, the sorption tests indicated that PP/POE blend foams showed larger oil‐uptake capacities than pure PP foams. In addition, cyclic compression tests showed that PP/POE open‐cell foams had excellent ductility and significantly improved recoverability compared to pure PP foams. In cyclic sorption–desorption tests, the sorption kinetics was studied in terms of capacity and saturation time, showing that PP/POE foams kept larger sorption capacities for 10 cycles, with larger sorption rates and good reusability. Based on the high open‐cell content, the good hydrophobic and oleophilic properties, the high oil‐sorption capacity, the improved recoverability, the large sorption rate, and the good reusability in cyclic oil‐sorption performance, the PP/POE open‐cell foams have shown promise as potential oil sorbents in applications for oil spill cleanup. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43812.     

Degradable polyurethane foams based on disaccharides

New functional elastic polyurethane foams (PUF) degradable under environmental abiotic and biotic factors, retaining all the inherent properties of the conventional foams were synthesized using isocyanate precursors based on disaccharides (DS): lactose, maltose and saccharose. It was shown by the model reactions of monosaccharide glucose, and DS lactose and saccharose, with phenylisocyanate that both the primary and secondary hydroxyls of the carbohydrates reacted to form urethanes. The main properties of DS‐based foams (PUF/DS) were found to be similar to PUF foam (matrix) prepared with conventional polyols. However, the new PUF/DS were found to undergo enhanced acid/alkaline hydrolysis and degradation compared with PUF matrix when incubated in soil. Mass losses of incubated PUF/DSs significantly exceeded the actual carbohydrate content 28.6%, and in 12 months reached 39.58 (PUF‐4), 53.31(PUF‐8), and 47.25 (PUF‐12). In contrast, under the same conditions PUF matrix lost only 2–2.5%, confirming that incorporation of natural compounds into the polymer chain impacted the degradation processes. PUF/DS were characterized by FTIR, ¹H NMR, ebullioscopy, and exclusion chromatography (molecular masses and molecular mass distribution of the oligomeric model), physical and mechanical tests (density, tensile strength, relative elongation, moisture absorption, vapor permeability), morphology, and degradation in the soil. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42131.     

Microbial uptake of diesel oil sorbed on soil and oil spill clean‐up sorbents

Sorbent effects in the microbial uptake of diesel oil were determined for black cotton soil (BCS) and two oil spill clean‐up sorbents, ie peat sorb and spill sorb. Biodegradation studies were conducted in mass transfer limited batch slurry microcosms using microorganisms capable of direct interfacial uptake of diesel oil. Under identical loading conditions, the amounts of diesel oil initially loaded on the various sorbents were 178, 288 and 649 mg g^?1 for BCS, spill sorb and peat sorb, respectively. Total biodegradation of sorbed diesel was comparable for all the sorbents (45–52 mg), however, the biodegradation rates were significantly different. Peat sorb demonstrated a distinct initial lag phase, the biodegradation rate in spill sorb was initially slower, whereas biodegradation at a high rate commenced immediately for BCS. The maximum biodegradation rates observed for BCS, spill sorb and peat sorb microcosms were 7.9, 5, and 2.9 mg day^?1, respectively. Thus, the maximum biodegradation rate increased as the diesel oil loading decreased. Our results indicate that spill clean‐up sorbents have greater bioavailability limitations compared with soils and this is linked with their significantly higher loading capacity and internal porosity. Copyright © 2005 Society of Chemical Industry     

Catalytic degradation of waste high-density polyethylene into fuel products using BaCO3 as a catalyst

Waste high-density polyethylene (HDPE) was degraded thermally and catalytically using BaCO₃ as a catalyst under different conditions of temperature, cat/pol ratio and time. The oil collected at optimum conditions (450 °C, 0.1 cat/pol ratio and 2 h reaction time) was fractionated at different temperatures and fuel property of the fractions and parent oil was evaluated by their physicochemical parameters for fuel tests. The results were compared with the standard values for gasoline, kerosene and diesel oil. Boiling point distribution (BPD) curves were plotted from the gas chromatographic study of the samples and compared with that of the standard gasoline, kerosene and diesel. The oil samples were analyzed using GC/MS in order to find out their composition. The physical parameters and the composition of the parent oil and its fractions support the resemblance of the samples with the standard fuel oils. The light fractions best match with gasoline, the middle fractions match with kerosene and the heavier fractions match with diesel oil in almost all of the characteristic properties.     

Properties of rigid polyurethane foams blown by HCFC 141B and distilled water

Rigid polyurethane foams (PUFs) were prepared from polymeric 4,4′‐diphenylmethane diisocyanate, polyester polyol, 1,4‐butane diol, silicone surfactant, hydrochlorofluorocarbon (HCFC) 141B, and distilled water. The properties and structure of the PUFs were investigated with differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and a universal testing machine. The density of the PUF blown by distilled water and/or HCFC 141B decreased from 175.7 to 28.2 kg/m³ with an increase of blowing agents. From the SEM results, the average cell size of the PUF blown by distilled water increased from 150 to 290 μm with the distilled water content. From the DSC results, the glass‐transition temperature (T_g) of the PUF blown by distilled water increased from 85.7 to 101.7°C with increasing distilled water content, whereas the T_g of the PUF blown by HCFC 141B remained unchanged with HCFC 141B content. The compressive strength and modulus of the PUF blown by a mixture of distilled water and HCFC 141B was increased from 0.13 to 0.25 MPa and from 3.00 to 7.23 MPa, respectively, with the distilled water content at the sample density of about 44.0 kg/m³. The increase of the compressive strength and modulus of the PUF at the same density was related to the increase of the T_g from 86.0 to 100.9°C. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 486–493, 2001     

Catalytic conversion of palm oil to fuels and chemicals

The conversion of palm oil to hydrocarbons using a shape selective zeolite catalyst is reported in this work. Palm oil was passed over HZSM-5 catalyst in a fixed bed micro-reactor and the reactor was operated at atmospheric pressure, a temperature range of 360 to 420°C and weight hourly space velocity (WHSV) of 2 to 4 h^?1. The main objective was to study the effect of reaction temperature and oil space velocity on the conversion and selectivity of gasoline range hydrocarbons. The results show that 40 to 70wt% of the palm oil can be converted to aromatics and hydrocarbons in the gasoline, diesel and kerosene range, light gases, coke and water. The maximum gasoline range hydrocarbons yield of 40wt% of total product formed was obtained at 400°C and 2 h^?1 space velocity.     

Flexible polyurethane foams synthesized employing recovered polyols from glycolysis: Physical and structural properties

Polyurethane (PU) is one of the most important polymers with a global production of 17.565 million tons, which makes its recycling an urgent task. Besides, the main goal of PU recycling is to recover constituent polyol as a valuable raw material that allows to obtain new PU with suitable properties. Split‐phase glycolysis can be considered the most interesting PU recycling process since provides high‐quality recovered products in terms of polyol purity. The aim of this work was to evaluate several recovered polyols as replacement of the raw flexible polyether polyol in the synthesis of new flexible PU foams. These recovered polyols come from the split‐phase glycolysis of different types of PU foams and employing as cleavage agents diethylene glycol or crude glycerol (biodiesel byproduct). The influence of the foam waste type and of the cleavage agent on the foams properties was analyzed. The recovered polyols were evaluated by performing several foaming tests according to the method of free expansion foaming of conventional flexible foam. Synthesized flexible foams containing different proportions of recovered polyols were characterized by means of scanning electron microscopy, density and tensile properties; obtaining similar and sometimes even better values compared to the foams manufactured from commercial polyols. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45087.     

Properties of water‐blown rigid polyurethane foams with reactivity of raw materials

Rigid polyurethane foams (PUFs) were prepared from polymeric 4,4‐diphenylmethane diisocyanate (PMDI; having functionality of 2.9), polyether polyols, silicone surfactant, amine catalysts, and distilled water. The effects of reactivity on the properties such as density, compressive and flexural strength, and glass‐transition temperature (T_g) of the PUF samples were studied. The kinetic rate of forming the PUF samples was increased with the catalyst and water content. With increasing OH value and functionality of the polyols, the density and compressive strength of the PUF samples also increased. For the PUF samples synthesized with polyols having high functionality (>5), the flexural strength of the PUF samples decreased with the functionality of the polyols. With increasing OH value and functionality of the polyols, the T_g of the PUF increased because of an increase in the degree of crosslinking of the PUF samples. The T_g value and compressive strength of the PUF samples were observed to increase with the NCO index. From this result, it was suggested that the increase in the T_g value and compressive strength of the PUF samples may be attributable to the additional crosslinks that arose from allophonate and biuret formation by the supplementary reactions of excess PMDI. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2334–2342, 2004     

Characterization of polyurethane foams prepared from liquefied sawdust by crude glycerol and polyethylene glycol

The aim of this study was to investigate polyurethane foams (PUF) properties obtained from crude glycerol (CG) and polyethylene glycol (PEG) based liquefaction of sawdust. The four types of foam were prepared by producing polyols from different weight loadings of PEG to CG as the liquefaction solvent. The produced polyurethane foams showed densities from 0.042 to 0.08 g/cm³ and compressive strengths from 200 to 311 kPa. The foams obtained from CG/PEG based liquefaction, had more uniform and regular cell structure than foams derived from liquefaction by CG. Also with the increasing percentage of PEG to CG in liquefaction, closed cell content of the synthesized foams increased and the size of cells decreased. The thermal conductivity of the produced foams was between 0.031 and 0.040 W/m K. Foams produced from liquefaction by binary solvent had lower thermal conductivity. However all foams showed approximately similar thermal degradation curves; maximum thermal decomposition temperature was seen for the foam produced from higher weight ratio of PEG to CG in liquefaction. PU foams produced from PEG/CG based liquefaction process had improved properties over from foams derived from sawdust liquefaction by CG.     

Evaluation of flexible postconsumed polyurethane foams modified by polystyrene grafting as sorbent material for oil spills

This work studies the possibility of reusing flexible postconsumed polyurethane foams modified by grafting with polystyrene as a sorbent material for the mitigation of oil spills. Different foams were evaluated via crude oil sorption and retention experiments, density, and morphological analyses. The foams with the best performance were chemically modified by grafting with polystyrene under different conditions (initiator concentration, styrene volume, and reaction time) in a system initiated by oxi‐reduction of Ce(IV) from an amoniacal ceric nitrate solution. A three‐level factorial design was used to study the influence of the variables. The foams were characterized via spectroscopy (XPS/ESCA and infrared) and water and oil sorption. Foam modification via grafting with polystyrene showed to be a viable alternative to increase its oil sorption ability. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

New alginate foams: Box‐Behnken design of their manufacturing; fire retardant and thermal insulating properties

A new method for preparing alginate foams with progressive release of copper in the presence of sodium lauryl sulfate (SLS, foaming agent) has been designed. Copper acts as the ionotropic gelling agent through the reaction of copper carbonate with gluconolactone. The process does not require freeze‐drying contrarily to the conventional method used for preparing macroporous alginate foams. The new materials investigated in this study have remarkable thermal properties, including thermal conductivity lower than 0.041 W m^?1 K^?1 and low heat release (below 2 kJ g^?1), which allows labeling these foams self‐extinguishing materials. An experimental design methodology, based on a Box‐Behnken plan with three parameters and three levels, is successfully used for evaluating the impact of the amounts of alginate, SLS, and copper carbonate on the productivity, apparent density, and shrinking at air‐drying. It yielded an optimization of the process for the manufacturing of light, and stable/rigid insulating and thermally stable materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45868.     

Modification of tung oil–based polyurethane foam by anhydrides and inorganic content through esterification process

In this study, we have reported the synthesis of modified polyol from tung oil. The synthesis involves three steps: first, conversion of tung oil to hydroxylated tung oil by hydroxylation; second, alcoholysis with triethanolamine; and finally, the esterification of polyester polyol when reacted with phthalic anhydride (PA) or maleic anhydride (MA). Boric acid is also introduced into the polyol by chemical modification, which enhances the thermal properties of polyurethane foam (PUF). PUF is formulated by the reaction between polyol and isocyanate. A systematic comparison of flame retardancy and mechanical and thermal properties of modified PUF has been examined. The structural properties of modified polyol were characterized by Fourier transform infrared spectroscopy, proton NMR spectroscopy, and gel permeation chromatography, while the thermal and mechanical properties of the formulated PUF were studied by scanning electron microscopy, limiting oxygen index, differential scanning calorimetry, Izod impact, and flexural and compression strength. Thus PUF prepared from modified polyol with a proper distribution of soft and hard segments possesses better mechanical and thermal properties. The PA‐modified foams show better properties compared to unmodified and MA‐modified foams due to the aromaticity and crosslinking behavior of PA. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45786.     

PET开孔泡沫的制备及其吸油性能研究

研究了均苯四甲酸二酐（PMDA）添加量、发泡温度和压力降对聚对苯二甲酸乙二醇酯（PET）开孔泡沫形成的影响。研究发现,当发泡温度为216℃,PMDA添加量为0.6份,压力降较高时,可以制备发泡倍率35倍、开孔率96.3%的PET开孔泡沫。将聚四氟乙烯（PTFE）和有机改性蒙脱土（MMT）引入PET开孔泡沫的制备,研究发现PTFE和MMT具有异相成核作用,减小了泡孔尺寸,拓宽了PET开孔发泡窗口温度,在（222～228℃）较宽的发泡温度窗口范围内成功制备了泡孔尺寸更小（10～100μm）、发泡倍率高达40倍的PET开孔泡沫。开孔泡沫可吸收汽油、柴油、煤油、轻质原油和重质原油等各种石油产品,本文对高开孔率开孔泡沫的吸油性能进行了研究,其吸收能力约为8～30 g/g。     

Controlled Experimental Study on Removing Diesel Oil Spillages Using Agricultural Waste Products

Diesel oil was used as adsorbate, while corn stalk, wheat straw and sawdust were used as natural sorbents for adsorbing and absorbing pure oil and oil in water. The results showed that all three agricultural wastes absorbed diesel. The corresponding saturated sorption amounts of wheat straw, corn stalk and sawdust were 8.54 g g^–1, 7.03 g g^–1 and 8.2 g g^–1. The optimum conditions found were: corn stalk particle size between 830 and 1700 μm, oscillation frequency of 0 r min^–1, i.e., no wave movement, oil film thickness of 0.55 mm and adsorbent dosage of 0.29 g; sawdust particle size between 830 and 1700 μm, oscillation frequency of 0 r min^–1, oil film thickness of 0.55 mm and adsorbent dosage of 0.25 g; wheat straw particle size between 500 and 830 μm, oscillation frequency of 0 r min^–1, oil film thickness of 0.55 mm and adsorbent dosage of 0.24 g.     

2003年我国石油进出口状况分析

2003年我国石油(包括原油及石油产品)进口总量为12962万吨。原油进口总量再创历史记录,达9112万吨,同比增长31.3%;石油产品中以燃料油、石油沥青的进口量增长迅速;汽煤柴出口量保持上升态势。本文对2003年我国原油及石油产品进出口来源情况及特点进行了详尽的分析与说明。     

乌兰管道首站北疆原油综合评价

对乌兰管道首站北疆原油进行了综合评价。结果表明,该原油密度大（867.3 kg/m3）,硫含量低（0.1%）,蜡含量高（11.46%）,属于中质低硫高蜡原油。重整原料和汽油馏分烷烃含量较高,适宜做乙烯裂解料。煤油馏分硫含量高,柴油馏分氮含量高,均需加强精制效果。减压蜡油酸值高、黏度指数低,不适合生产高黏度指数润滑油,Cp较高（56.34%）,CA低（7.69%）,残炭值低（0.013%）,重金属含量较小,是催化裂解的优良原料。渣油较轻,属于第二类渣油,硫含量较小（0.26%）,沥青质含量较低（1.5%）,是理想的催化裂化原料的掺料或焦化原料。     

Gasoline permeation behavior and mechanical properties of polyamide 6/nanoclay,polyamide 6/PE‐g‐maleic anhydride blend,and polyamide 6/PE‐g‐maleic anhydride/clay nanocomposite

In this article, polyamide 6 (PA6)/clay nanocomposites, PA6/polyethylene grafted maleic anhydride (PE‐g‐MA) blends, and PA6/PE‐g‐MA/clay nanocomposites were prepared and their gasoline permeation behavior and some mechanical properties were investigated. In PA6/clay nanocomposites, cloisite 30B was used as nanoparticles, with weight percentages of 1, 3, and 5. The blends of PA6/PE‐g‐MA were prepared with PE‐g‐MA weight percents of 10, 20, and 30. All samples were prepared via melt mixing technique using a twin screw extruder. The results showed that the lowest gasoline permeation occurred when using 3 wt % of nanoclay in PA6/clay nanocomposites, and 10 wt % of PE‐g‐MA in PA6/PE‐g‐MA blends. Therefore, a sample of PA6/PE‐g‐MA/clay nanocomposite containing 3 wt % of nanoclay and 10 wt % of PE‐g‐MA was prepared and its gasoline permeation behavior was investigated. The results showed that the permeation amount of PA6/PE‐g‐MA/nanoclay was 0.41 g m^?2 day^?1, while this value was 0.46 g m^?2 day^?1 for both of PA6/3wt % clay nanocomposite and PA6/10 wt % PE‐g‐MA blend. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40150.     

The effect of different palm oil‐based bio‐polyols on foaming process and selected properties of porous polyurethanes

Rigid polyurethane foams were successfully prepared by blending up to 70 wt% of two different palm oil‐based bio‐polyols with a petrochemical polyether polyol. The bio‐polyols were synthesized by epoxidation–oxirane ring‐opening process using water (PP102) and diethylene glycol (PP147), respectively. Due to the high viscosity of both bio‐polyols the reactive mixture was heated to start the foaming reaction at about 50 °C. Under these conditions, the gelling reactions speed up as the amount of PP147 increases but slow down to a great extent when PP102 is used. The thermal conductivity of modified foams is higher and the closed cell content lower compared to reference ones, even when the bio‐foams present a lower apparent density. However, all foams exhibit reduced water absorption, excellent dimensional stability and better thermal stability at temperatures up to 400 °C than the control foam. Conversely, their mechanical and dynamic mechanical properties become poorer as the PP147 concentration increases and even more so if PP102 is used instead. PP147 foams containing up to 50% bio‐polyol could be used as a green replacement of petroleum‐based ones in applications where excellent behaviour in compression (the most affected properties) is not fundamental, with the additional advantages of reduced density and increased content of bio‐derived components. © 2017 Society of Chemical Industry