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10Pcs Laboratory Soxhlet Extractor 250-1000ml Glass Serpentine Fat Extractor With Electric Heating Mantle Graham Condenser Glass Extraction Device Glassware Distilling Apparatus (250ml)

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A Soxhlet extractor is a kind of laboratory equipment. It is made of glass. Franz von Soxhlet invented it in 1879. It has a flask, an extraction chamber, and a condenser. It can be used for solid-liquid extractions. A highly significant advance in extraction technology, perhaps the most significant occurrence in the field for the century that followed, occurred 140 years ago with the first report of the Soxhlet extractor, a unique continuous–discontinuous device (1). This was the same year, 1879, that a 31-year old Franz Ritter von Soxhlet (Figure 1) became a professor of agricultural chemistry at the Technical University of Munich. Jensen's history on the origins of the device credits a laboratory glassblower, known only as "Herr Szombathy," as a significant contributor to this creation (2). Soxhlet is discontinuous in that it relies on a number of solvent siphon cycles. It is continuous in the sense that solvent is continuously evaporated from the solvent reservoir flask and condensed. This continuous–discontinuous process minimizes channeling of solvent through the sample, as can occur with continuous flow methods. So, Soxhlet is more correctly a batch process. The key to this solvent cycling is the constant-level siphon, based on a Pythagoras Cup. (Readers who are fans of Martyn Poliakoff's Periodic Videos may wish to view http://www.periodicvideos.com/videos/pythagoras_cup.htm.). If necessary, the collected extract can be evaporated to eliminate the solvent and concentrate the recovered material. This can be accomplished through the use of techniques such as rotary evaporation or freeze drying.

Fig. 1 Oxidation process of graphite into graphene oxide. The graphite is oxidized by an improved Hummers' method. The contaminated oxidized graphite is washed in a Soxhlet extractor: (1) condenser, (2) Soxhlet extractor, (3) oxidized graphite in a cup, (4) boiling washing solvent. At the end of the process a neutral GO with no contamination is produced.

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A. Cuesta, P. Dhamelincourt, J. Laureyns, A. Martínez-Alonso and J. M. D. Tascón, Carbon, 1994, 32, 1523–1532 CrossRef CAS. We put our sample powder inside the thimble. The powder has to be covered from the bottom with a cotton ball to avoid powder directly falling into the thimble. And also cover the powder from the top.

In terms of solvents savings, the main advantage is the ability to use the same solvent repeatedly, instead of replacing the solvent in every washing step. This can cut the costs by 7–10 fold. It is suitable for a variety of organic solvents with different boiling points, and the temperature control range is wide, from room temperature +5°C to 300°C. Still pot (the still pot should not be overfilled and the volume of solvent in the still pot should be 3 to 4 times the volume of the Soxhlet chamber) The elemental composition of the product can be reconfirmed by XPS. Although XPS is a surface analysis method, the exact elemental measurement for a bulk material might be less accurate. Elemental composition of the Soxhlet washed, the traditional washed and the commercial GO is plotted in Fig. 3b and tabled in Table S4. † In all samples the carbon and oxygen contents are similar. The sulphur content was relatively large, as a result of the sulfuric acid used in Hummers' method. Yet, Soxhlet washed GO contained less sulfur than the centrifuged GO (3.63 to 5.93%). The commercial GO contains 1.69% of N, which was not detected in the GO prepared in our lab. As we do not know the production process of the commercial GO we cannot explain the source of this nitrogen impurity. The full XPS survey and C 1s scans are also included in Fig. S4 and S5, † respectively.

Abstract

Raman spectroscopy of the rGO rinsed by Soxhlet introduces a typical graphene-like spectrum, with an intense and sharp G-band at 1585 cm −1 and a minor D-band peak at 1370 cm −1 ( Fig. 4f). The spectra of the rGO demonstrate high similarity to the graphite precursor, with the most notable difference being the shoulder at 2670 cm −1 present only in graphite's spectra. Importantly, the outstanding I D/ I G ratio of 0.67 indicates a high graphitic level. This proves the impressive effectiveness of the production process. In fact, the high quality rGO obtained with the Soxhlet method suggests a promising approach for a cost-effective, eco-friendly, and safe process for up-scaling production of graphene. XRD measurement of the produced rGO further confirms the graphene-like structure of the reduced GO ( Fig. 4g). A suitable extraction solvent, normally enough to cover the solid sample, is added to the flask. To allow for efficient extraction, the solvent should have a lower boiling point than the target material. Electrochemical impedance spectra (EIS) of rGO electrodes are presented in Fig. 5b. A typical semicircle shape at the high frequency domain was followed by an almost vertical line at the lower frequencies. This proves the highly capacitive behavior of the electrodes with low internal resistivity. 31 The turning point is at 2.1 Hz. M. D. P. Lavin-Lopez, A. Romero, J. Garrido, L. Sanchez-Silva and J. L. Valverde, Ind. Eng. Chem. Res., 2016, 55, 12836–12847 CrossRef CAS.

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