检索结果-南通市图书馆

Chemically modified silica gel with 1-{4-[(2-hydroxy-benzylidene)amino]phenyl}ethanone:Synthesis, characterization and application as an efficient and reusable solid phase extractant for selective removal of Zn(Ⅱ) from mycorrhizal treated fly-ash samples

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2013年第6期25卷 1252-1261页

作者： R.K.Sharma Aditi Puri Anil Kumar Alok Adholeya 2 Green Chemistry Network Centre Department of ChemistryUniversity of Delhi Biotechnology and Management of Bioresources Division The Energy and Resource Institute

1-{4-[（2-hydroxy-benzylidene）amino]phenyl}ethanone functionalized silica gel was synthesized and used as a highly efficient, selective and reusable solid phase extractant for separation and preconcentration of trace amount of Zn（II） from environmental matrices. The adsorbent was characterized by fourier transform infrared spectroscopy （FT-IR）, elemental analysis,~3C CPMAS NMR spectroscopy, scanning electron microscopy （SEM）, thermogravimetric analysis （TGA） and BET surface area analysis. The dependence of zinc extraction on various analytical parameters such as pH, type and amount of eluent, sample flow rate and interfering ions were investigated in detail. The material exhibited superior adsorption efficiency for Zn（II） with high metal loading capacity of 1.0 mmol/g under optimum conditions. After adsorption, the recovery （〉 98%） of metal ions was accomplished using 1.0 mol/L HNO3 as an eluent. The sorbent was also regenerated by microwave treatment in milder acidic environment （0.1 mol/L HNO3）. The lower detection limit and preconcentration factor of the present method were found out to be 0.04 ~tg/L and 312.5 respectively. The modified silica surface possessed excellent selectivity for the target analytes and the adsorption/desorption process remained effective for at least ten consecutive cycles. The optimized procedure was successfully implemented for the extraction of Zn（II） from mycorrhizal treated fly ash and pharmaceutical samples with reproducible results.

关键词： solid phase extraction silica gel preconcentration fly-ash zinc

silica gel from Chemical Glass Bottle Waste as Adsorbent for Methylene Blue:Optimization Using BBD

在线全文

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2023年第12期11卷 4007-4023页

作者： Suprapto Suprapto Putri Augista Nur Azizah Yatim Lailun Ni’mah Chemistry Department Faculty of Science and Analytical DataInstitut Teknologi Sepuluh NopemberSurabayaIndonesia

This research focuses on the effective removal of methylene blue dye using silica gel synthesized from chemical glass bottle waste as an environmentally friendly and cost-effective *** adsorption process was optimized using Box-Behnken Design(BBD)and Response Surface Methodology(RSM)to investigate the influence of pH(6;8 and 10),contact time(15;30 and 45 min),adsorbent mass(30;50 and 70 mg),and initial concentration(20;50 and 80 mg/L)of the adsorbate on the adsorption *** BBD was conducted using Google Colaboratory software,which encompassed 27 experiments with randomly assigned *** silica gel synthesized from chemical glass bottle was characterized by XRD,FTIR,SEM-EDX and *** adsorption result was measured by spectrophotometer *** optimized conditions resulted in a remarkable methylene blue removal efficiency of 99.41%.Characterization of the silica gel demonstrated amorphous morphology and prominent absorption bands characteristic of *** Langmuir isotherm model best described the adsorption behavior,revealing chemisorption with a monolayer coverage of methylene blue on the adsorbent surface,and a maximum adsorption capacity of 82.02 mg/***,the pseudo-second-order kinetics model indicated a chemisorption mechanism during the adsorption *** findings highlight the potential of silica gel from chemical glass bottle waste as a promising adsorbent for wastewater treatment,offering economic and environmental *** investigations can explore its scalability,regenerability,and reusability for industrial-scale applications.

关键词： Glass bottle waste silica gel adsorption waste treatment methylene blue Box-Behnken design

Dynamical Behaviour of H2O in silica gel

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2002年第5期19卷 711-713页

作者：王燕董顺乐 DepartmentofPhysics OceanUniversityofQingdaoQingdao266003

The vibrational spectra of silica gel with low concentrations of water, 3% and 10%, were studied by inelastic neutron scattering at 5K. The experimental spectrum for 3% water in silica gel shows dramatic changes compared to the spectra for the other known ice phases in the energy transfer region of 2-140meV. Its intermolecular librational band is shifted to lower energy by about 20meV (or by a factor of 1.43) compared to ice Ih, and shows a similar librational band with liquid at 290K. A significant excess of low-frequency vibration modes (silica gel exhibits a strong softening of hydrogen bonds compared to bulk normal ice and all the other known ice phases.

关键词： silica gel

Gypsum-based silica gel Humidity-controlling Composite Materials:Preparation,Characterization,and Performance

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 337-344页

作者：李曦冉茂宇 School of Architecture Huaqiao UniversityXiamen 361021China Xiamen Key Laboratory of Ecological Building Construction Xiamen 361021China

Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based composites were compared with adding different silica gel particle size and *** morphological characteristics,the isothermal equilibrium moisture content curve,moisture absorption and desorption rate,moisture absorption and desorption stability,and humidity-conditioning performance were tested and *** experimental results show that,compared with pure-gypsum,the surface structure of the gypsum-based composites is relatively loose,the quantity,density and aperture of the pores in the structure *** absorption and desorption capacity increase along with the increase of silica gel particle size and silica gel *** 3 mm silica gel particle size is added with a mass ratio of 40%,the maximum equilibrium moisture content of humidity-controlling composites is 0.161 g/g at 98% relative humidity(RH),3.22 times that of *** moisture absorption and desorption rates are increased,the equilibrium moisture absorption and desorption rates are 2.68 times and 1.61 times that of pure-gypsum at 58.5% RH,*** gypsum-based composites have a good stability,which has better timely response to dynamic humidity changes and can effectively regulate indoor humidity under natural conditions.

关键词： humidity controlling composite materials gypsum silica gel

Efficient CO_2 capture on low-cost silica gel modified by polyethyleneimine

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2012年第3期21卷 319-323页

作者： Ke Wang Hongyan Shang Lin Li Xinlong Yan Zifeng Yan Chenguang Liu Qingfang Zha State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdao 266555ShandongChina

In this work, a series of polyethyleneimine （PEI） functionalized commercial silica gel were prepared by wet impregnation method and used as CO2 sorbent. The as-prepared sorbents were characterized by N2 adsorption, FT-1R and SEM techniques. CO2 capture was tested in a fixed bed reactor using a simulated flue gas containing 15.1% CO2 in a temperature range of 25-100 ~C. The effects of sorption temperature and amine content on CO2 uptake of the adsorbents were investigated. The silica gel with a 30 wt% PEI loading manifested the largest CO2 uptake of 93.4 mgcoz/gadsorbent （equal to 311.3 mg^oz/gPEI） among the tested sorbents under the conditions of 15.1% （v/v） CO2 in N2 at 75 ~C and atmospheric pressure. Moreover, it was rather low-cost. In addition, the PEI-impregnated silica gel exhibited stable adsorption-desorption behavior during 5 consecutive test cycles. These results suggest that the PEI-impregnated silica gel is a promising and cost-effective sorbent for CO2 capture from flue gas and other stationary sources with low CO2 concentration.

关键词： silica gel C02 capture polyethyleneimine flue gas

The Adsorption of Pb(II)Using silica gel Synthesized from Chemical Bottle Waste:Optimization Using Box-Behnken Design

在线全文

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2023年第6期11卷 2913-2924页

作者： Yatim Lailun Ni’mah Nabila Eka Yuningsih Suprapto Suprapto Department of Chemistry Faculty of Science and Data AnalyticsInstitut Teknologi Sepuluh NopemberSurabayaIndonesia

The adsorption of Pb(II)on silica gel synthesized from chemical glass bottle waste has been *** effect of independent variables(adsorbent dose,initial concentration of Pb(II),contact time,and pH)on the Pb(II)removal from water was evaluated and optimized using the Response Surface Methodology(RSM).Under optimized conditions(adsorbent dose:20 mg;contact time:30 min;initial Pb(II)concentration:120 mg.L^(−1);and pH:8),the removal of Pb(II)was 99.77%.The adsorption equilibrium data obtained from the batch experiment were investigated using different isotherm *** Langmuir isotherm model fits the experimental *** shows that the surface of the silica gel synthesized from chemical bottles waste was covered by a Pb(II)*** analysis showed that the synthesized silica gel had a SiO_(2) content of 75.63%.Amorphous silica was observed from XRD ***-EDX characterization showed that Pb was adsorbed on the silica gel *** analysis showed that silica gel has irregular particles with a surface area of 297.08 m2.g^(−1) with a pore radius of 15.74 nm calculated from BET analysis.

关键词： Chemical bottle waste silica gel adsorption box-behnken design response surface methodology

Efficient and solvent-free synthesis of bis-indolylmethanes using silica gel supported aluminium chloride as a reusable catalyst

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第8期22卷 939-942页

作者： Kaveh Parvanak Boroujeni Kamran Parvanak Department of Chemistry Shahrekord UniversityShahrekord 115Iran Islamic Azad University Shahr-e-Rey BranchIran

Stable and non-hygroscopic silica gel supported aluminium chloride（SiO_2-AlCl_3）,which is prepared easily from cheap and commercially available compounds was found to be an environmentally friendly heterogeneous catalyst for the condensation of indole with aldehydes and ketones to afford bis-indolylmethanes at room temperature under solvent-free *** catalyst can be reused up to five times after simple washing with ether.

关键词： Bis-indolylmethanes Indole Carbonyl compounds silica gel Aluminium chloride

Selective Pre-concentration and Solid Phase Extraction of Mercury（Ⅱ） from Natural Water by silica gel-loaded （E）-N-（1-Thien-2＇-ylethylidene）-1,2-phenylenediamine Phase

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2007年第10期25卷 1536-1541页

作者： MOGHIMI, Ali Department of Chemistry Varamin Campus Islamic Azad University Varamin Iran

silica gel-loaded （E）-N-（1-thien-2＇-ylethylidene）-1,2-phenylenediamine （TEPDA） phase was synthesized based on physical adsorption approaches. The stability of a chemically modified TEPDA especially in concentrated hydrochloric acid that was then used as a recycling and preconcentration reagent allowed the further uses of silica gel-loaded immobilized TEPDA phase. The application of this silica gel-loaded phase to sorption of a series of metal ions was performed by using different controlling factors such as the pH of the metal ion solution and the equilibration shaking time by the static technique. This difference was interpreted on the basis of selectivity incorporated in these sulfur containing silica gel-loaded TEPDA phases. Hg（Ⅱ） was found to exhibit the highest affinity towards extraction by these silica gel-loaded TEPDA phases. The pronounced selectivity was also confirmed by the determined distribution coefficients （Kd） of all the metal ions, showing the highest value reported for mercury（Ⅱ） extraction by the silica gel immobilized TEPDA phase. The potential applications of the silica gel immobilized TEPDA phase to selective extraction of mercury（Ⅱ） from aqueous solution were successfully accomplished and preconcentration of low concentration of Hg（Ⅱ）（30 pg·mL^-1） from natural tap water with a preconcentration factor of 200 for Hg（Ⅱ） off-line analysis was conducted by cold vapor atomic absorption analysis.

关键词： silica gel (E)-N-(1-thien-2'-ylethylidene)-1,2-phenylenediamine (TEPDA) solid phase extraction

Preconcentration and determination of trace copper(II) in natural water using silica gel modified with 1-(2-pyridylazo)-2-naphthol

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 1989年第1期1卷 121-124页

作者： Tong Shenyang, Liu Feng, Li Kean Department of Chemistry,Peking University,Beijing China

Trace copper (II) in water can be preconcentrated using silica gel modified with 1-(2-pyridylazo)-2-naphthol (PAN) and be determined spectrophotometri-cally. The conditions for the preconcentration were studied. The method was applied to both artificial and natural water samples and the results suggest that copper (II) of ppb level in water can be measured accurately after the preconcentration.

关键词： PAN silica gel copper preconcentration.