Effect of polymer concentration on the polymer adsorption-induced permeability reduction in low permeability reservoirs

Park, Hyemin,Han, Jinju,Sung, Wonmo Elsevier 2015 ENERGY Vol.84 No.-

<P><B>Abstract</B></P> <P>This study presented the effect of polymer adsorption-induced permeability reduction on oil recovery, particularly in low permeability system. The polymer injecting experiments were conducted in a quarter of five-spot pattern with concentrations generally applied. Especially, by using the field oriented two-dimensional sandstone, we attempted to analyze the combined effect of polymer retention for concentration and high velocity near injection on oil recovery.</P> <P>Particularly in low permeable sandstone, oil recovery was not proportionally enhanced with increase in polymer concentration, rather decreased at concentrations above 1,000 ppm in this experiment. This could be understood by polymer adsorption phenomena corresponding to concentrations. The polymer adsorption layer formed at high concentration clogged effective pore radius by up to 59.8%, compared to clean sandstone and the permeability greatly decreased from 56 to 1.5 mD, resulting in rather decreased oil recovery. For this reason, there should be an optimum concentration for maximizing the oil recovery. It was also confirmed by shear rate analysis. At high concentration, the shear rate near injection where has the highest velocity was greater than critical rate. This means that polymer molecules adsorbed to mono-layer of adsorption by hydraulic force, and the adsorption became additionally thicker and hindered the oil flow.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effect of polymer adsorption with polymer concentrations on oil recovery is analyzed. </LI> <LI> In low permeable systems, oil recovery rather decreased above optimum concentration. </LI> <LI> Polymer adsorption-induced permeability was greatly reduced at high concentration. </LI> <LI> In two-dimensional system, high velocity near injection intensified the adsorption. </LI> </UL> </P>

탄산염암 저류층에 저염수주입공법과 폴리머공법의 복합 적용에 따른 오일 생산량 평가

이연경(Yeonkyeong Lee),김수연(Sooyeon Kim),이원석(Wonsuk Lee),장영호(Youngho Jang),성원모(Wonmo Sung) 한국가스학회 2018 한국가스학회지 Vol.22 No.5

저염수 기반 폴리머공법은 기존의 폴리머공법과 저염수주입공법의 시너지 효과를 통해 오일회수율을 더욱 증진시킬 수 있는 기술로서, 공법의 효율성을 극대화하기 위해서는 폴리머의 특성을 고려한 저염수 설계가 필수적이다. 이에 본 연구에서는 탄산염암 오일 저류층에 저염수 기반 폴리머공법 적용 시, 주입수의 pH와 주입수 내 PDI(Potential Determining Ion) 이온 중 SO₄<SUP>2-</SUP> 이온이 오일 생산량에 미치는 영향을 규명하고자 하였다. 우선, 주입수의 pH와 주입수 내 SO₄<SUP>2-</SUP>의 농도에 따른 폴리머 분자의 안정성 및 흡착 현상을 분석하였다. 그 결과, 주입수의 pH와 주입수 내 SO₄<SUP>2-</SUP>의 농도에 상관없이, 주입수 내 SO₄<SUP>2-</SUP>가 함유되어 있는 경우 폴리머 용액의 안정성이 확보되었다. 그러나, 폴리머 용액의 정체 현상 분석 결과, 주입수의 pH가 중성인 7일 때에는 SO₄<SUP>2-</SUP> 이온이 폴리머의 흡착을 방해하여 SO₄<SUP>2-</SUP>의 농도가 높을수록 폴리머 흡착층의 두께가 더 얇은 것으로 나타난 반면에, 주입수가 pH 4로 산성인 경우에는 폴리머 용액을 주입함에 따라 폴리머의 흡착량이 증가하여 폴리머 용액의 유동성이 크게 낮아졌다. 다음으로, 저염수 효과에 의한 습윤도 변환을 살펴본 결과, 주입수가 중성일 때에는 SO₄<SUP>2-</SUP>의 농도가 높을수록 탄산염암 표면에 흡착되어 있던 오일의 탈착이 증가하여 암석의 습윤도가 친유성에서 친수성으로 크게 변환되었다. 반면에, 주입수가 산성일 때에는 용해와 폴리머 흡착의 복합적 작용으로 인해 전체 코어 시스템의 습윤도는 중성일 때에 비해 비교적 덜 변환되는 것으로 나타났다. 이에 따라 SO₄<SUP>2-</SUP> 농도가 높은 중성의 저염수 기반 폴리머 용액을 주입할 경우 오일 생산량은 저염수주입공법에 비해 최대 12.3% 증진되어 보다 양호한 EOR(Enhanced Oil Recovery) 효과를 얻을 수 있는 것으로 평가되었다. Low-salinity water based polymerflooding (LSPF) is one of promising enhanced oil recovery (EOR) method that has the synergetic effect of combining polymer injection method and low-salinity water injection method. In order to maximize EOR efficiency, it is essential to design low-salinity water appropriately considering the properties of polymer. In this aspect, the main purpose of this study is to investigate the effect of pH and SO₄<SUP>2-</SUP><SUP></SUP> ion which one of PDI (Potential Determining Ion) on oil production when applying LSPF to carbonate oil reservoir. First, the stability and adsorption of polymer molecule were analyzed in different pH of injection water and SO₄<SUP>2-</SUP> concentration in injection water. As a result, regardless of pH and SO42- concentration, when SO₄<SUP>2-</SUP> ion was contained in injection water, the stability of polymer solution was obtained. However, from the result of polymer retention analysis, in neutral state of injection water, since SO₄<SUP>2-</SUP> interfered the adsorption of polymer, the adsorption thickness of polymer was thinner as SO₄<SUP>2-</SUP> concentration was higher. On the other hand, when injection water was acidic as pH 4, the amount of polymer adsorption increased with the injection of polymer solution, so the mobility of polymer solution was greatly lowered. From the results of wettability alteration due to low-salinity water effect, in the case of neutral injection water injected, as SO₄<SUP>2-</SUP> concentration was increased, more oil which attached on rock surface was detached, altering wettability from oil-wet to water-wet. On the other hand, in acidic condition, due to complex effect of rock dissolution and polymer adsorption, wettability of the entire core system was less altered relatively to neutral condition. Therefore, it was evaluated that better EOR efficiency was obtained when injecting low-salinity water based polymer solution containing high concentration of SO42- with neutral condition, enhancing the oil production up to 12.3% compared to low-salinity water injection method.

Heavy metal removal applications using adsorptive membranes

VO THI SINH,MUHAMMAD MOHSIN HOSSAIN,정형모,김경훈 나노기술연구협의회 2020 Nano Convergence Vol.7 No.36

Water is a significant natural resource for humans. As such, wastewater containing heavy metals is seen as a grave problem for the environment. Currently, adsorption is one of the common methods used for both water purification and wastewater treatment. Adsorption relies on the physical and chemical interactions between heavy metal ions and adsorbents. Adsorptive membranes (AMs) have demonstrated high effectiveness in heavy metal removal from wastewater owing to their exclusive structural properties. This article examines the applications of adsorptive membranes such as polymeric membranes (PMs), polymer-ceramic membranes (PCMs), electrospinning nanofiber membranes (ENMs), and nano-enhanced membranes (NEMs), which demonstrate high selectivity and adsorption capacity for heavy metal ions, as well as both advantages and disadvantages of each one all, are summarized and compared shortly. Moreover, the general theories for both adsorption isotherms and adsorption kinetics are described briefly to comprehend the adsorption process. This work will be valuable to readers in understanding the current applications of various AMs and their mechanisms in heavy metal ion adsorption, as well as the recycling methods in heavy ions desorption process are summarized and described clearly. Besides, the influences of morphological and chemical structures of AMs are presented and described in detail as well.

Facile synthesis of a mesoporous organic polymer grafted with 2-aminoethanethiol for Hg²⁺ removal

Ravi, Seenu,Ahn, Wha-Seung Elsevier 2018 Microporous and mesoporous materials Vol.271 No.-

<P><B>Abstract</B></P> <P>By varying the amount of AlCl<SUB>3</SUB> catalyst, highly interconnected lamella-shaped (IPOP) and spherically structured porous organic polymers (SPOP) were synthesized from terephthaloyl chloride and <I>p</I>-quaterphenyl via the Friedel–Crafts benzoylation reaction. The newly prepared materials were characterized by scanning electron microscopy, N<SUB>2</SUB> adsorption-desorption isotherms, X-ray photoelectron spectroscopy, and tested for Hg<SUP>2+</SUP> removal in water after functionalization with 2-aminoethanethiol (NS). The stability under different pH and temperature conditions was confirmed, and the equilibrium and kinetics of Hg<SUP>2+</SUP> adsorption were examined by varying the contact time, adsorbate concentration, and pH. The maximum adsorption capacities for Hg<SUP>2+</SUP> by IPOP-NS and SPOP-NS were 769 and 526 mg g<SUP>−1</SUP>, respectively, at 25 °C and pH 5, and the adsorption isotherm data conformed well to the Langmuir model. Adsorption equilibrium for IPOP-NS was reached within 10 min and exhibited a remarkable distribution coefficient of 1.06 × 10<SUP>8</SUP> mL g<SUP>−1</SUP>. The kinetics of Hg<SUP>2+</SUP> adsorption followed the pseudo-second-order model. The influence of co-existing ions such as Na<SUP>+</SUP>, K<SUP>+</SUP>, Ca<SUP>2+</SUP>, Pb<SUP>2+</SUP>, Mg<SUP>2+</SUP>, and Fe<SUP>3+</SUP> was also examined. IPOP-NS was superior in overall performance when compared to SPOP-NS and most of the other reported materials. IPOP-NS could be reused for a minimum of 10 consecutive runs without any detectable loss in adsorption capacity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel mesoporous polymers were synthesized (IPOP/SPOP) and grafted with 2-aminoethanethiol (NS). </LI> <LI> IPOP-NS exhibited exceptional Hg<SUP>2+</SUP> capture of 769 mg g<SUP>−1</SUP> in water with fast kinetics. </LI> <LI> IPOP-NS showed high stability in boiling water, aqueous HCl, and NaOH. </LI> <LI> IPOP-NS was reusable 10 cycles without deterioration in adsorption capacities. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Development of high capacity Li+ adsorbents from H2TiO3/polymer nanofiber composites: Systematic polymer screening, characterization and evaluation

Chosel P. Lawagon,Grace M. Nisola,Rosemarie Ann I. Cuevas,김헌,이성풍,정욱진 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.70 No.-

Various polymers were systematically screened as matrices for H2TiO3 Li+ adsorbent. H2TiO3/polymerswere electrospun as nanofibers (NF), characterized, and evaluated via response surface methodologywith central composite design for Li+ adsorption experiments. Polyacrylonitrile (PAN) was determined asthe most suitable H2TiO3 support. H2TiO3/PAN hydrophilicity and its favorable NF structure providedsufficient feed interaction. The Li+ adsorption was Langmuir-type with maximum capacity = 72.75 mg g 1and adsorption rate = 1.89 10 4 g mg 1 min 1. H2TiO3/PAN is Li+-selective, with a thermodynamicallyfavorable adsorption. Stable performance and durability during cycled adsorption/desorption runs proveH2TiO3/PAN NF as highly effective composite Li+ adsorbent.

겔라이트를 혼입한 분말형 폴리머 시멘트 경화체의 흡착성능 평가

이전호 ( Lee Jeon-ho ),이창우 ( Lee Chang-woo ),황우준 ( Hwang Woo-jun ),이상수 ( Lee Sang-soo ) 한국건축시공학회 2022 한국건축시공학회 학술발표대회 논문집 Vol.22 No.1

In order to solve problems such as acceleration of resource use and environmental pollution, experiments were conducted with the aim of producing indoor finishing materials that can adsorb fine dust and carbon dioxide using gelite and polymer, which are porous materials. Based on the previous experiment, gelite was substituted at each level in a matrix having a polymer S738P substitution rate of 12.5%, and the results are as follows. As the substitution rate of gelite increased, the amount of fine dust and carbon dioxide adsorption increased, which is believed to be due to physical adsorption due to the high porosity of gelite. However, further experiments are needed as the overall adsorption amount is not high due to the filling inside the matrix due to the polymer.

Adsorption characteristics of benzene on electrospun-derived porous carbon nanofibers

Shim, Wang Geun,Kim, Chan,Lee, Jae Wook,Yun, Je Jung,Jeong, Young Il,Moon, Hee,Yang, Kap Seung Wiley Subscription Services, Inc., A Wiley Company 2006 Journal of applied polymer science Vol.102 No.3

<P>The adsorption properties of polyacrylonitrile (PAN) carbon nanofibers fabricated by using an electrospinning route were assessed for their applicability as a novel alternative adsorbent. Commercial fiber, A–10, was chosen for comparison. Nitrogen adsorption/desorption isotherms and gravimetric techniques were used to examine the porous structure, adsorption equilibrium, kinetics, and the energetic heterogeneity of the prepared adsorbent. The nitrogen adsorption and desorption isotherms showed that PAN carbon nanofibers are highly microporous with small amounts of mesoporous regions. The equilibrium data of benzene was obtained at three different temperatures (343.15, 383.15, and 423.15) K with pressures up to 4 kPa. The data correlated successfully with the Toth isotherm equation. In addition, by using this isotherm model, the adsorption affinity and isosteric enthalpy of adsorption were determined. The results of the isosteric enthalpy of adsorption and adsorption energy distribution tests/equations revealed that although PAN carbon nanofibers have a heterogeneous surface, they seem to be more homogeneous than commercial carbon fibers. Moreover, the mass transfer and thermal desorption results showed that shallow pores contained within PAN carbon nanofibers may be effective adsorbents for removing toxic compounds. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2454–2462, 2006</P>

Development of high capacity Li⁺ adsorbents from H₂TiO₃/polymer nanofiber composites: Systematic polymer screening, characterization and evaluation

Lawagon, Chosel P.,Nisola, Grace M.,Cuevas, Rosemarie Ann I.,Kim, Hern,Lee, Seong-Poong,Chung, Wook-Jin THE KOREAN SOCIETY OF INDUSTRIAL AND ENGINEERING 2019 JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY -S Vol.70 No.-

<P><B>Abstract</B></P> <P>Various polymers were systematically screened as matrices for H<SUB>2</SUB>TiO<SUB>3</SUB> Li<SUP>+</SUP> adsorbent. H<SUB>2</SUB>TiO<SUB>3</SUB>/polymers were electrospun as nanofibers (NF), characterized, and evaluated via response surface methodology with central composite design for Li<SUP>+</SUP> adsorption experiments. Polyacrylonitrile (PAN) was determined as the most suitable H<SUB>2</SUB>TiO<SUB>3</SUB> support. H<SUB>2</SUB>TiO<SUB>3</SUB>/PAN hydrophilicity and its favorable NF structure provided sufficient feed interaction. The Li<SUP>+</SUP> adsorption was Langmuir-type with maximum capacity=72.75mgg<SUP>−1</SUP> and adsorption rate=1.89×10<SUP>−4</SUP> gmg<SUP>−1</SUP> min<SUP>−1</SUP>. H<SUB>2</SUB>TiO<SUB>3</SUB>/PAN is Li<SUP>+</SUP>-selective, with a thermodynamically favorable adsorption. Stable performance and durability during cycled adsorption/desorption runs prove H<SUB>2</SUB>TiO<SUB>3</SUB>/PAN NF as highly effective composite Li<SUP>+</SUP> adsorbent.</P> <P><B>Highlights</B></P> <P> <UL> <LI> LIS HTO in various polymeric supports were electrospun as nanofibers (NFs). </LI> <LI> Hydrophilic polyacrylonitrile (PAN) as NF is the most suitable HTO matrix. </LI> <LI> HTO/PAN NF has minimal losses in Li<SUP>+</SUP> adsorption capacity (<I>q</I>) and kinetics. </LI> <LI> HTO/PAN NF has excellent Li selectivity, it achieved maximum <I>q<SUB>m</SUB> </I> =72.75mgg<SUP>−1</SUP>. </LI> <LI> HTO/PAN NF is durable, recyclable, and suitable for various aqueous Li<SUP>+</SUP> sources. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Modelling of an adsorption chiller with adsorbent-coated heat exchangers: Feasibility of a polymer-water adsorption chiller

Kim, Dong-Seon,Chang, Young-Soo,Lee, Dae-Young Elsevier 2018 ENERGY Vol.164 No.-

<P><B>Abstract</B></P> <P>An analytical model is developed for an adsorption chiller with adsorbent-coated heat exchangers, where adsorbent is deposited on heat exchanger surface in thin film to improve heat and mass transfer characteristics. Approximate solutions are obtained from the simplified governing equations for the heat exchanger and then used to predict performance of the chiller. The analytical model provides the heat and mass fluxes in the system in explicit functions of a few dimensionless numbers including <I>N</I> <SUB> <I>t</I> </SUB>, <I>Ja</I>, <I>γ</I> and <I>C</I> <SUB> <I>r</I> </SUB>. The analytical model is validated via comparison with a two-dimensional numerical model in wide ranges of design and operating parameters. The maximum discrepancy is found ca. 13% in SCP and 0.02 point in COP. Performance of the chiller is discussed regarding the influences of various design and operating parameters. Some experimental results are also analyzed with the analytical model and the results are discussed focusing on the performance of polymer-coated heat exchangers.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Analytical solution is obtained for an adsorbent-coated heat exchanger. </LI> <LI> A simple analytical model is developed for an adsorption chiller. </LI> <LI> The analytical model is validated via comparison with a two-dimensional numerical model. </LI> <LI> Performance of a polymer-water adsorption chiller is discussed. </LI> </UL> </P>

Effect of Polymer Adsorption in Magnetic Nanoparticle Dispersion by Rheological and Magnetic Characterizations

윤관한,이영실 한국고분자학회 2023 폴리머 Vol.47 No.2

The relations between rheological properties and dispersion state of polymer adsorbed magnetic particles in the dispersion are investigated to characterize the amount of adsorbed polymer. Also, the transverse susceptibility measurement as magnetic property has been performed to characterize the magnetic dispersion. Dispersions of Co-γ-Fe2O3nanoparticles were prepared using a binder polymer with polar groups, which adsorbed on the surface of the magnetic nanoparticles, in the molecular chains. The adsorbed layer thickness increases with decreasing particle volume fraction because of large amount of solvent penetration in the adsorbed layer resulting in the increase of the radius of gyration of the adsorbed polymer. For the magnetic nanoparticle dispersion with the volume fraction below the interaction limit, there is shear thickening in steady shear viscosity, which is resulted from the polymer bridges. According to the transverse susceptibility measurement, there are more individual particles in the magnetic nanoparticle dispersion at low volume fraction of nanoparticle.