Co-solvent concentration impact on the cloud point behavior of 2- and 3-ingredient systems of the poly(tridecyl methacrylate) in supercritical CO2

Cloud point data of the 2- and 3-ingredient poly(tridecyl methacrylate) [P(TDMA)] mixture in supercritical CO2 and dimethyl ether (DME) have been obtained experimentally with the variable volume-view cell at a high pressure.

Kajian pengaruh kondisi dekomposisi analisis logam tembaga dalam sedimen di pelabuhan ikan Sendang Biru secara SSA

Cu that is absorbed in marine sediments can accumulate in the food chain even in small concentrations. Cu analysis in these sediments can be used to analyze water pollution due to human activities. The purpose of this study was to determine the level of Cu in decomposed sediments with variation of solvent concentration, variation of decomposition time, and variation of solvent volume and then compare the result of Cu analysis decomposed using HNO3 solvent under effective condition with aqua regia solvent. The method of analysis used is decomposition technique of sediment sample by using reflux and then analyzed with AAS.. Cu yang terserap dalam sedimen laut dapat berakumulasi dalam rantai makanan meskipun dalam konsentrasi kecil. Analisis Cu dalam sedimen ini dapat digunakan untuk menganalisis pencemaran perairan akibat aktivitas manusia. Tujuan penelitian ini adalah menentukan kadar Cu dalam sedimen yang didekomposisi dengan variasi konsentrasi pelarut, variasi waktu dekomposisi, dan variasi volume pelarut dan membandingkan hasil analisis Cu yang didekomposisi menggunakan pelarut HNO3 pada kondisi efektif dengan pelarut akuaregia. Metode analisis yang digunakan yaitu teknik dekomposisi sampel sedimen dengan menggunakan refluks dan dianalisis dengan SSA.

Analysis of Catechins in Gambir West Sumatra

Gambir contains functional compounds that are included in the class of polyphenol compounds. The polyphenol compounds in gambir are mainly catechins, a natural substance that has antioxidant properties. The purpose of this study was to obtain catechin compounds from Gambir extract, to determine the solvent concentration and the right extraction temperature to obtain catechin compounds in Gambir, and to increase the selling value of Gambir latex in the Farmer community. To get the results of catechins in Gambir, this research was carried out using the infundation method. The yield of the extract was mostly found at a solvent concentration of 45% ethanol, a temperature of 105 oC and a time of 3 hours, namely 81%. Qualitative test using FeCl3 reagent can be seen that in the filtrate extracted from gambir there are catechins which show a blackish green color when dropped with FeCl3

Sharpening a Cyclic Solvent Injection Technique in a Heavy Oil Reservoir from the Variation of the Nitrogen Injected as Dispersing: A Field Pilot, Colombia

This paper analyzes the use of a cyclic solvent injection technique (CSI) as a non-thermal EOR alternative to cyclic steam stimulation (CSS) for increasing the heavy oil recovery in a shallow reservoir located at the middle Magdalena basin in Colombia. A pilot well with less than 30% of water-cut and 10.9 °API was selected. Heavy natural gasoline of 30 °API obtained from the same reservoir was injected by using nitrogen (N2) as dispersing gas. Three procedures were performed being the procedure A, a Solvent slug injection of 60 bbl through the annular pushed and dispersed by 46,444 m3 (1,640 Mscf) of N2 immiscible (considering the low reservoir pressure). The procedure B consisted of injecting the same Solvent volume, but this time pushed by a third part of the N2 injected previously 15,481 m3 (547 Mscf). The procedure C consisted of only inject the same N2 volume than B procedure to analyze the heavy oil response without Solvent. There were collected production data, °API (by hydrometer), gas-flow and gas-gravity values using a liquid level software. Knowing the °API of each component in the laboratory—Solvent and heavy oil—the Solvent concentration from the real °API produced in production stages was calculated. All procedures had 48 hours of soaking, followed by a flowing process to tank to carefully release the excess of N2 before starting the production stage, avoiding gas lock issues. Without considering the Solvent injected, incremental oil production in procedure A was 232 bbl, in procedure B was 120 bbl and for procedure C, incremental oil only reached 11 bbl. With the last result it was determined the N2 injection by itself as a production mechanism without the Solvent effect in the in-situ heavy oil had a negligible effect on incremental oil. The gas-gravity showed the gas composition became heavier along the time, this considering the high-frequency N2 injections swept the methane near the well, requiring more time to produce the N2 traces from the porous media. The excess of N2 as a heavy Solvent dispersing mechanism does not warrant a better dilution effect since as observed in A and B procedures, Solvent concentration in the early production stage never dropped below 35% (17 °API), regardless of the N2 volume injected in the first two days. Finally, although A procedure had more incremental oil production (+93% than B), less N2 injected in B procedure was more efficient (+55% than A) regarding the incremental oil and N2 injected ratio (ONR).

Total Polyphenol Content in Green Tea (Camellia Sinensis) Using Maceration Extraction with Comparison of Ethanol – Water Solvent

Green tea is a kind of plant that have an active polyphenol substance. Polyphenol is a group of compounds that has a role as a natural antioxidant. Solvent comparison used affects the extracted polyphenol content. This study aims to compare the total polyphenol content in green tea from maceration method with solvent concentration variation of 30%, 50%, and 70%. In this research, green tea is extracted by using the maceration method with ethanol – water solvent concentration of 30%, 50%, and 70%. The total polyphenol content determination in green tea was conducted by using the Follin-Ciocalteu method by UV-Vis spectrophotometre, and using gallic acid as a standard. According to this research, the yield calculation of ethanol extract in green tea with the ethanol concentration of 30%, 50%, and 70% are 41.220%; 39.979 %; and 47.971 %. The total polyphenol content test of green tea with the ethanol concentration of 30%, 50%, and 70% are 11.294 mg GAE/100 g; 16.377 mg GAE/100g; and 15.640 mg GAE/100 g. The anova statistical analysis result shows that there is a significant difference of total polyphenol content of green tea extract with ethanol concentration 30% and 50%, also there is no significant difference in the ethanol concentration of 70%. The highest result of total polyphenol of green tea extract with the ethanol concentration of 50%. It is suggested to conduct a further study on the type of the polyphenol substance in green tea.

Discovery of the Crystal Phase Transition on Lead-free Cesium Manganese Bromine Perovskite Nanocrystal by Solvent Concentration

We have been demonstrated the crystal phase transition for lead-free cesium manganese bromine perovskite nanocrystal synthesized by the modified hot-injection method due to change the concentration of solvent (trioctylphosphine; TOP). The compositions to be synthesized were determined by the amount of TOP solvent, and the structure phase of nanocrystal was changed from hexagonal CsMnBr3 to tetragonal Cs3MnBr5 as the amount of TOP solvent increased. The emission peaks of CsMnBr3 and Cs3MnBr5 nanocrystals were observed at 650 nm (red) and 520 nm (green), respectively. After a durability test at 85 °C and 85% humidity for 24 h, the lead-free perovskite CsMnBr3 nanocrystal powder maintained its initial emission intensity, and the metal halide Cs3MnBr5 nanocrystal powder exhibited an increase in red emission due to the post-synthesis of CsMnBr3 nanocrystals.

Solvent diffusion mechanism of PMMA/ acetone coated glass fiber fabric during curing process

Fabric it is not an impermeable substrate because of fiber porosity. To study the solvent diffusion mechanism of coated fabric in the curing process, the drying model of PMMA/acetone coated glass fiber fabric was established. This drying model was verified by confocal Raman spectroscopy. Finally, the impact of fabric structure, thickness and porosity on the solvent diffusion process in coated fabrics was studied by the model. It was shown that the predicted solvent concentrations by the model were consistent with the experimental values. This model can be used to quantitatively calculate the solvent concentration at any position and at any time inside the coating film during the drying process. Moreover, it can also predict the curing time and residual solvent concentration of the coating fabric required to reach drying equilibrium. Compared with coated 3/1 twill, 5/3 satin and 2/1 twill, the solvent diffusion of coated plain fabric was faster during curing. Under the same environmental conditions, the thinner the fabric was and the greater the porosity was, the shorter the curing time was. The fitting equations for fabric thickness, fabric porosity and drying time were obtained, which can provide a theoretical guidance for the preparation, performance research and drying conditions optimization of PMMA coated textile materials.

Recovery of Valuable Solutes from Organic Solvent/Water Mixtures via Direct Contact Membrane Distillation (DCMD) as a Non-Heated Process

Recently, the demand for the recovery of valuable solutes from organic solvents/water mixtures has increased in various fields. Furthermore, due to the abundance of heat-sensitive valuable solutes, the demand for non-heated concentration technologies has increased. In this study, the direct contact membrane distillation (DCMD) using hydrophobic polyvinylidene difluoride (PVDF) hollow fiber membranes was investigated to confirm the possibility of recovering valuable solutes from organic solvents/water mixtures as a non-heated process. The DCMD with 1000 ppm NaCl aqueous solution achieved 0.8 kg/m2·h of vapor flux and >99.9% of NaCl retention, even at feed and coolant temperatures of 25 and 10 °C, respectively. Furthermore, when DCMD was conducted under various conditions, including feed temperatures of 25, 35 and 45 °C, and organic solvent concentration of 15, 30 and 50 wt%, using ethanol/water and acetonitrile/water mixtures containing 1000 ppm NaCl. A surfactant was also used as a valuable solute, in addition to NaCl. As a result, it was found that the total vapor flux increased with increasing temperature and concentration of organic solvents, as the partial vapor pressure of the organic solvents increased. Additionally, no solute leaked under any condition, even when the surfactant was used as a valuable solute.

Variation concentration effect of propyleneglycol, glycerin, and polyethyleneglycol 400 to physical properties and dissolution rate of loratadine liquisolid tablet

Objectives This study aimed to evaluate the variation concentration effect of propyleneglycol, glycerin, and polyethyleneglycol 400 as a nonvolatile solvent on the physical properties and dissolution rate of the loratadine liquisolid tablet. Methods The tablet was formulated into 10 formulas, where nine were liquisolid and one was conventional (CT). The concentration of propyleneglycol, glycerin, and polyethyleneglycol used in liquisolid tablets were 14, 15, and 16%. Furthermore, the mixture was evaluated based on flow properties and compressibility index. The tablet was evaluated based on hardness, friability, disintegration time, and dissolution, and the data obtained was evaluated with ANOVA or Kruskal–Wallis statistic program. Results The result showed that flow properties, disintegration time, and dissolution have a significant value less than 0.05. The tablet friability for all concentration solvents, hardness at 14 and 15% solvent concentration, and compressibility index at 15 and 16% have significant value more than 0.05. The 16% propyleneglycol type solvent concentration tablet has the physical properties and contains the best solution Conclusions From the result, it is reasonable to conclude that F7 is the tablet with all the physical properties and the best dissolution.

Optimization of active coagulant agent extraction method from Moringa Oleifera seeds for municipal wastewater treatment

An enhanced and different method for the active coagulant agent extraction from Moringa Oleifera seeds powder (MOSP) was established and compared to the conventional extraction method in distillate water. In the improved method, MOSP were extracted using sodium chloride as solvent at different concentrations to extract more coagulant agent from Moringa Oleifera and enhance coagulation activity. In this study, MOSP were initially processed and oil content was removed to minimize coagulant concentration usage (MOSP-EO). Moringa Oleifera seeds powder was characterized by both X-ray and FTIR analysis. Ultrasound treatment as well was considered as an additional treatment for MOSP-EO to investigate its effect on coagulant agent extraction process improvement. Coagulation/flocculation experiments were conducted to assess coagulant extraction performance realized through various conditions. The effect of coagulant dosage, solvent concentration and ultrasound exposition duration were investigated for a real effluent of municipal wastewater treatment. Among the three studied NaCl concentrations, 1.0 M was found to be the best solvent concentration for high turbidity removal of more than 97% using 140 mg/L of MOSP-EO compared to extraction in distillate water 88% using 170 mg/L of the same coagulant. NaCl 1.0 M demonstrated the best performance in biochemical oxygen demand (BOD5) removal as well, where more than 98% of municipal wastewater initial BOD5 was eliminated. Mixing MOSP-EO assisted with ultrasound waves at different treatment periods did decrease the active coagulant agent extraction and thus showed its inconvenient for Moringa Oleifera coagulation activity usage.