Roles of solid components on the sorption of trichloroethylene (TCE) onto natural solids from the vapor phase

1994 ◽  
Vol 30 (7) ◽  
pp. 1-11 ◽  
Author(s):  
Yoshihisa Shimizu ◽  
Noboru Takei ◽  
Yutaka Terashima
Keyword(s):  
Humic Acid ◽  
Moisture Content ◽  
Iron Oxides ◽  
Solid Phase ◽  
Reduction Rate ◽  
Amorphous Iron ◽  
Swelling Clays ◽  
Aluminosilicate Gel ◽  
Amorphous Aluminosilicate ◽  
Solid Phases

The sorption of trichloroethylene (TCE) from the vapor phase was investigated by batch sorption experiments. The role of solid components in natural solids was evaluated with a model solid phase system, consisting of six individual model solid phases (humic acid, montmorillonite, kaolinite, amorphous aluminosilicate gel, amorphous iron oxides, and amorphous manganese oxides) and two binary model solid phases (montmorillonite with amorphous aluminosilicate gel and montmorillonite with amorphous iron oxides). Experimental results indicated that swelling clays, which are represented by the montmorillonite, are a dominant sorbent in natural solids. The amorphous metal oxides of aluminosilicate and iron effectively block the sorption site of the swelling clay. The water associated with model solid phases (i.e., moisture content) reduces the sorption. The reduction rate, normalized with respect to the sorption onto each model solid phase of zero moisture content, is greater for the inorganic model solid phases than for humic acid. The sorption experiments with natural solids observed a greater reduction rate for the natural solid of low organic carbon content. Therefore, it was hypothesized that moisture content of the swelling clays in a natural solid is smaller than that of the organic matter.

The effects of colloidal humic substances on the movement of non-ionic hydrophobic organic contaminants in groundwater

1998 ◽  
Vol 38 (7) ◽  
pp. 159-167 ◽  
Author(s):  
Y. Shimizu ◽  
H. Sogabe ◽  
Y. Terashima
Keyword(s):  
Humic Substances ◽  
Iron Oxides ◽  
Organic Compounds ◽  
Organic Contaminants ◽  
Hydrophobic Organic Compounds ◽  
Hydrophobic Organic Contaminants ◽  
Third Phase ◽  
Aluminosilicate Gel ◽  
Amorphous Aluminosilicate ◽  
Inorganic Constituents

A controlled experimental study of the sorption of colloidal humic substances (humic acid) and a non-ionic hydrophobic organic compound (naphthalene) onto typical inorganic constituents of aquifer solids was performed using four types of model solid phases {i.e., individual model solids (montmorillonite, kaolinite, amorphous aluminosilicate gel, and amorphous iron oxides) and combined model solids (montmorillonite coated by amorphous aluminosilicate gel or iron oxides)}, which are synthesized in the laboratory. The batch experimental results indicated that the sorption of non-ionic hydrophobic organic compounds and colloidal humic substances onto the aquifer solids is significantly influenced by the solid composition. And it was also suggested that the non-ionic hydrophobic organic compounds which have greater hydrophobicity are considered to be sorbed and stabilized by the mobile colloidal humic substances in groundwater, and these colloids may act as a third phase that can increase the amount of compounds that the flow of groundwater can transport. On the other hand, the non-ionic hydrophobic organic contaminants of smaller hydrophobicity may be retarded significantly with the sorption of colloidal humic substances onto the aquifer solids.

Sorption of Humic Materials onto Inorganic Surfaces for the Mitigation of Facilitated Pollutant Transport Processes

1992 ◽  
Vol 26 (5-6) ◽  
pp. 1221-1228 ◽  
Author(s):  
H. M. Liljestrand ◽  
I. M-C. Lo ◽  
Y. Shimizu
Keyword(s):  
Humic Acid ◽  
Pollutant Transport ◽  
Transport Processes ◽  
Montmorillonite Clay ◽  
Barrier Materials ◽  
Aluminosilicate Gel ◽  
Humic Materials ◽  
Solid Phases ◽  
Inorganic Constituents ◽  
Slurry Walls

The transport of hydrophobic organic pollutants in groundwaters is facilitated by sorption of these chemicals onto natural organics and transport with these materials. One strategy to mitigate pollutant transport through clay liners and slurry walls is to reduce the transport of the natural organics by enhancing their sorption onto the containment barrier materials. A controlled experimental study of the adsorption of humic acid onto typical inorganic constituents of soils was performed using two types of model solid phases: 1) pure solids (washed Na-montmorillonite clay, amorphous ferrihydrite, and amorphous aluminosilicate gel) and 2) binary combined phases (Na-montmorillonite coated with ferrihydrite or aluminosilicate gel). The combined phases were synthesized for a range of metal to clay mineral ratios. Adsorption tests were conducted to investigate the relative sorption affinity of these solid phases for humic acid. Addition of a ferrihydrite coating was found to increased the sorption of humic acid onto montmorillonite clay.

scholarly journals Analysis of the Chloroacetanilide Herbicides in Water Using SPME with CAR/PDMS and GC/ECD

2005 ◽  
Vol 88 (4) ◽  
pp. 1236-1241 ◽  
Author(s):  
Ying-Ming Hwang ◽  
Yih-Gang Wong ◽  
Wu-Hsiung Ho
Keyword(s):  
Humic Acid ◽  
Ph Value ◽  
Limit Of Detection ◽  
Solid Phase ◽  
Standard Addition ◽  
Electron Capture Detection ◽  
Detection Analysis ◽  
Salt Addition ◽  
Chloroacetanilide Herbicides ◽  
Relative Standard

Abstract The solid-phase microextraction (SPME) technique using a 75 mm film of carboxen/polydimethylsiloxane was applied to the analysis of chloroacetanilide herbicides (acetochlor, alachlor, butachlor, metolachlor, and propachlor) residues. The feasibility of SPME with gas chromatography electron capture detection analysis has been evaluated. The effects of experimental parameters such as magnetic stirring, salt addition, humic acid addition, pH value, and extraction time, as well as desorption temperature and time, were investigated. Analytical parameters such as linearity, repeatability and limit of detection were also evaluated. The inhibition of humic acid to the extraction of chloroacetanilide herbicides was observed. A standard addition method for calibration was recommended to reduce deviations caused by matrix interferences. The proposed method provided a simple and rapid analytical procedure for chloroacetanilide herbicides in water with limits of detection 0.002–0.065 μg/L for deionized water, and 0.005–0.22 μg/L for farm water. The relative standard deviations (n = 5) for analyses of farm water were 7–20% for 0.5 μg/L chloroacetanilide herbicides. This application was illustrated by the analysis of sample collected from farm water in the Chung-hwa area, Taiwan.

Pathways and Mechanisms for Removal of Dissolved Organic Carbon from Leaf Leachate in Streams

1981 ◽  
Vol 38 (1) ◽  
pp. 68-76 ◽  
Author(s):  
Clifford N. Dahm
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Clay Minerals ◽  
Iron Oxides ◽  
Amorphous Solid ◽  
Microbial Utilization ◽  
Physical Chemical ◽  
Fine Particulate ◽  
Solid Phases ◽  
Aluminum And Iron Oxides

Removal of dissolved organic carbon (DOC) from water resulting from adsorption and microbial uptake was examined to determine the importance of biotic and abiotic pathways. Physical–chemical adsorption to components of the stream sediment or water and biotic assimilation associated with the microbial population was determined in recirculating chambers utilizing leachate from alder (Alnus rubra). Adsorptive mechanisms were further separated into interactions involving (1) specific clay minerals, (2) amorphous solid phases of hydrous aluminum and iron oxides, and (3) fine particulate organic matter. Physical–chemical adsorptive mechanisms for alder leachate removal exhibited rapid kinetic equilibration between the DOC and solid phases, but only a specific fraction of the DOC, likely containing certain chemical functional groups, was adsorbed. The amorphous aluminum and iron oxides possessed a much higher potential capacity than the clay minerals or fine particulate organics for DOC adsorption. Microbial uptake of DOC from the alder leachate was kinetically slower than adsorptive uptake. However, microbial activity was overall much more effective in the removal and degradation of the total DOC pool leached from alder leaves. Over a 48-h period, 97% of added 14C labeled leachate was removed from solution by adsorption (~ 20%) and microbial utilization (~ 77%). The rate of microbial uptake was 45 μg C/g sediment C∙h−1 or 14 mg C∙m−2∙h−1.

Solubilities and solubility products of thorium hydroxide under moderate temperature conditions

2018 ◽  
Vol 106 (8) ◽  
pp. 655-667
Author(s):  
Shogo Nishikawa ◽  
Taishi Kobayashi ◽  
Takayuki Sasaki ◽  
Ikuji Takagi
Keyword(s):  
Elevated Temperatures ◽  
Solid Phase ◽  
Size Distributions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Endothermic Process ◽  
Solid Phases ◽  
Solubility Products ◽  
Colloidal Species ◽  
Thorium Hydroxide

AbstractThe Th solubilities of the sample solutions that initially contained Th(OH)4(am) prepared by undersaturation and oversaturation methods in the pHcrange of 2.0–8.0 in a 0.5 M ionic strength solution of NaClO4and HClO4and stored at aging temperatures (Ta) of 298, 313 and 333 K were investigated in this study. After a certain period of time up to 40 weeks depending onTa, supernatants of the sample solutions were ultrafiltrated through 3 kDa membranes under the measurement temperature (Tm) of 298, 313 and 333 K. Size distributions of the colloidal species were investigated by ultrafiltration using membranes with different pore sizes ranging from 3 to 100 kDa, and the solid phases were examined by X-ray diffraction (XRD). The solubility of the sample solutions obtained after aging atTa=298 K using undersaturation method with continuous shaking was similar to those of dried precipitate of Th hydroxide. The solubilities obtained after aging atTa=313 and 333 K were lower than those atTa=298 K. The XRD spectra suggested that the crystallization of the solid phase proceeded under these elevated temperatures. The solubility of the sample solutions obtained after aging atTa=333 K using the oversaturation technique were similar to those prepared by undersaturation method and aged at the sameTa. A slight temperature dependence of the apparent solubilities on theTmwas observed in the sample solutions prepared by both methods. The solubility products$({K_{{\text{sp,}}{T_{\text{a}}}}}({T_{\text{m}}}))$after differentTaandTmwere determined from the solubility analysis. The observed increase in the formation constant$({K_{{\text{s,}}{T_{\text{a}}}}}({T_{\text{m}}}))$of Th4++(4+x)H2O(1)⇌Th(OH)4·xH2O(s,Ta)+4H+with increasingTmindicated that the reaction was endothermic. The enthalpy change$(\Delta_{r}H_{m\_ T_{\text{a}} \to {\text{cr}}}^{\circ} )$between the solid phases of Th(OH)4·xH2O(s,Ta) and ThO2(cr) suggested that the solid phase transformation from Th(OH)4·xH2O(s,Ta) to ThO2(cr) contains an endothermic process.

scholarly journals A Whole-Slurry Fermentation Approach to High-Solid Loading for Bioethanol Production from Corn Stover

Agronomy ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1790 ◽  
Author(s):  
Pablo G. del Río ◽  
Patricia Gullón ◽  
F.R. Rebelo ◽  
Aloia Romaní ◽  
Gil Garrote ◽  
...  
Keyword(s):  
Corn Stover ◽  
Crop Residue ◽  
Solid Phase ◽  
Solid Loading ◽  
High Solid ◽  
High Solid Loading ◽  
Second Generation Bioethanol ◽  
Liquid Phases ◽  
Solid Phases ◽  
Whole Slurry

Corn stover is the most produced byproduct from maize worldwide. Since it is generated as a residue from maize harvesting, it is an inexpensive and interesting crop residue to be used as a feedstock. An ecologically friendly pretreatment such as autohydrolysis was selected for the manufacture of second-generation bioethanol from corn stover via whole-slurry fermentation at high-solid loadings. Temperatures from 200 to 240 °C were set for the autohydrolysis process, and the solid and liquid phases were analyzed. Additionally, the enzymatic susceptibility of the solid phases was assessed to test the suitability of the pretreatment. Afterward, the production of bioethanol from autohydrolyzed corn stover was carried out, mixing the solid with different percentages of the autohydrolysis liquor (25%, 50%, 75%, and 100%) and water (0% of liquor), from a total whole slurry fermentation (saving energy and water in the liquid–solid separation and subsequent washing of the solid phase) to employing water as only liquid medium. In spite of the challenging scenario of using the liquor fraction as liquid phase in the fermentation, values between 32.2 and 41.9 g ethanol/L and ethanol conversions up to 80% were achieved. This work exhibits the feasibility of corn stover for the production of bioethanol via a whole-slurry fermentation process.

Simulation of Flow and Heat Transfer in a Moving Bed Reactor With Cross Flow

2008 ◽  
Author(s):  
Marcelo J. S. de Lemos
Keyword(s):  
Heat Transfer ◽  
Relative Velocity ◽  
Solid Phase ◽  
Cross Flow ◽  
Vertical Direction ◽  
Momentum Equation ◽  
Solid Matrix ◽  
Flow And Heat Transfer ◽  
Temperature Distributions ◽  
Solid Phases

Heat transfer in a porous reactor under cross flow is investigated. The reactor is modeled as a porous bed in which the solid phase is moving horizontally and the flow is forced into the bed in a vertical direction. Equations are time-and-volume averaged and the solid phase is considered to have a constant imposed velocity. Additional drag terms appearing the momentum equation are a function of the relative velocity between the fluid and solid phases. Turbulence equations are also affected by the speed of the solid matrix. Results show temperature distributions for several ratios of the solid to fluid speed.

On-line solid phase extraction of humic acid from environmental water and monitoring with flow-through chemiluminescence

The Analyst ◽  
2012 ◽  
Vol 137 (8) ◽  
pp. 1824 ◽  
Author(s):  
Jingya Qu ◽  
Hui Chen ◽  
Chao Lu ◽  
Zhihua Wang ◽  
Jin-Ming Lin
Keyword(s):  
Humic Acid ◽  
Solid Phase Extraction ◽  
Solid Phase ◽  
Environmental Water ◽  
Phase Extraction ◽  
On Line ◽  
Flow Through

Solid phase precipitates in (Zr,Th)-OH-(oxalate, malonate) ternary aqueous system

2009 ◽  
Vol 97 (4-5) ◽  
Author(s):  
Taishi Kobayashi ◽  
Takayuki Sasaki ◽  
I. Takagi ◽  
Hirotake Moriyama
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Solid Phase ◽  
Aqueous System ◽  
Carboxylate Ligand ◽  
X Ray Diffraction ◽  
Large Excess ◽  
X Ray ◽  
Acidic Conditions ◽  
Solid Phases

AbstractThe solubility-limiting solid phases in the ternary aqueous systems of Zr(IV)/OH/oxalate, Zr(IV)/OH/malonate, Th(IV)/OH/oxalate and Th(IV)/OH/malonate were characterized by elemental analysis, X-ray diffraction, thermogravimetric analysis and differential thermal analysis. The ternary solid phase of M(IV)/OH/carboxylate was observed to form, even under acidic conditions, depending on the pH and the concentration of carboxylate ligand. In the presence of a large excess of carboxylic acid, however; the binary M(IV)-carboxylate solid phase formed.

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