Studies on the Acetone Extraction of Raw Rubber. V. The Influence of Heating at 100° C. and Storage of the Acetone Extract on the Saponification Value

1936 ◽  
Vol 9 (1) ◽  
pp. 35-37
Author(s):  
Hidemaro Endô
Keyword(s):  
Steam Bath ◽  
Acetone Extract ◽  
Water Bath ◽  
Drying Time ◽  
Acetone Extraction ◽  
Saponification Value ◽  
And Storage ◽  
Hcl Solution

Abstract (1) When the acetone extract was heated at 100° C., the saponification value (AT) first diminished and then increased. (2) When the acetone extract was stored, the saponification value (AT) first increased and then diminished and returned to the original value. (3) The determination of the saponification value was carried out as follows: The sample was extracted for the required time, the acetone was evaporated off as rapidly as possible and the flask was dried in a steam bath for as short a time as possible. The drying time must not be over 15 minutes, and usually 5 minutes is sufficient. The dried flask was cooled and weighed, after which 20 cc. of 0.2 N alcoholic KOH was added and the flask heated on a water bath for 60 minutes. The excess alkali was titrated with 0.1 N HCl solution, using phenolphthalein as indicator.

Studies on the Acetone Extraction of Raw Rubber

1935 ◽  
Vol 8 (4) ◽  
pp. 604-612
Author(s):  
Hidemaro Endô
Keyword(s):  
Acid Value ◽  
Acetone Extract ◽  
Water Bath ◽  
Acetone Extraction ◽  
Saponification Value ◽  
Alcoholic Potash ◽  
Saponifiable Matter ◽  
Acetone Extracts ◽  
Hcl Solution

Abstract (1) For the determination of the saponification value of the acetone extract, 20 cc. 0.2 N alcoholic potash is added to the extract and the flask is heated on a water bath for 60 minutes. It is then titrated with 0.1 N HCl solution, using phenolphthalein as indicator. (2) When the saponification values of the acetone extracts of 8, 16, and 24 hours are compared, the saponification value of the 8 hour extract is seen to be high, while those of 16 and 24 hour extracts are low. This indicates (a) that the 8 hour extract contains a higher percentage of saponifiable matter than the 16 and 24 hour extracts; (b) the quantity of rubber hydrocarbon which is dissolved in the acetone extract increases with increasing time of extraction, and (c) the acid value of the acetone extract decreases during the period of extraction from 16 to 24 hours. (3) Regarding the saponification values (R) of the acetone extracts of 8, 16, and 24 hours, similar remarks may be made as in (2) above.

Studies on the Acetone Extraction of Raw Rubber. VII. The Time of Acetone Extraction of Raw Rubber and the Saponification Value of the Acetone Extract and Residue

1936 ◽  
Vol 9 (2) ◽  
pp. 308-310
Author(s):  
Hidemaro Endô
Keyword(s):  
Fatty Acids ◽  
Gradual Increase ◽  
Acid Value ◽  
Acetone Extract ◽  
Continuous Extraction ◽  
Acetone Extraction ◽  
Saponification Value ◽  
Saponifiable Matter ◽  
Acidic Compounds ◽  
Almost All

Abstract During acetone extraction of pale crepe, the free acids and saponifiable matter were extracted almost completely in 1 or 2 hours. The saponification value (A) had a tendency to decrease rapidly and to reach a minimum after 12 hours (in non-continuous extraction) or after 16 hours (in continuous extraction). The cause of the decrease of the saponification value (A) from the commencement of extraction up to the time mentioned is thought to be due to a gradual increase in the amount of extracted non-acidic compounds and unsaponifiable matter with increasing time of extraction, and to the neutralization of acids by other compounds, as by esterification. After reaching the minimum point, the saponification value (A) had a tendency to increase gradually. This increase is thought to be due to (1) a gradual increase of ester extracted, (2) the formation of acids by oxidation, and (3) the formation of free acids by decompositions of esters, though the last factor does not increase materially the saponification value. The change of saponification value of the acetone extract with increasing time of extraction is not due to any change in the type of compounds gradually extracted, but to a change in the acetone extract in the acetone solution during extraction. This is in agreement with the acid value. It was observed in a previous paper (III) that almost all of the free acids contained in pale crepe were extracted by acetone in 1 hour. But by extraction for 1 or 2 hours, a small portion of the saponifiable matter still remain unextracted. This remaining part could not be extracted even by prolonged extraction. It is believed, therefore, that the free fatty acids are dissolved in the saponifiable matter, and that the latter are dissolved in the rubber hydrocarbon. As the acetone extract is very labile, so far as the change of acetone extract is concerned, the acetone extract, whether it be dried or left in solution, should not be stored for too long a time. The results obtained by such long extraction by acetone as multiples of ten hours, as used by Whitby and Winn (J. Soc. Chem. Ind., 41, 336T (1923)), are thought to be quite unreliable.

scholarly journals Optimising storage conditions and processing of sheep urine for nitrogen cycle and gaseous emission measurements from urine patches

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alice F. Charteris ◽  
Karina A. Marsden ◽  
Jess R. Evans ◽  
Harry A. Barrat ◽  
Nadine Loick ◽  
...  
Keyword(s):  
Freeze Drying ◽  
Storage Conditions ◽  
Chemical Components ◽  
Gaseous Emissions ◽  
Gaseous Emission ◽  
Grazing Systems ◽  
And Storage ◽  
Sheep Urine ◽  
Country Specific

AbstractIn grazing systems, urine patches deposited by livestock are hotspots of nutrient cycling and the most important source of nitrous oxide (N2O) emissions. Studies of the effects of urine deposition, including, for example, the determination of country-specific N2O emission factors, require natural urine for use in experiments and face challenges obtaining urine of the same composition, but of differing concentrations. Yet, few studies have explored the importance of storage conditions and processing of ruminant urine for use in subsequent gaseous emission experiments. We conducted three experiments with sheep urine to determine optimal storage conditions and whether partial freeze-drying could be used to concentrate the urine, while maintaining the constituent profile and the subsequent urine-derived gaseous emission response once applied to soil. We concluded that filtering of urine prior to storage, and storage at − 20 °C best maintains the nitrogen-containing constituent profile of sheep urine samples. In addition, based on the 14 urine chemical components determined in this study, partial lyophilisation of sheep urine to a concentrate represents a suitable approach to maintain the constituent profile at a higher overall concentration and does not alter sheep urine-derived soil gaseous emissions.

scholarly journals Determination of the Chemical Composition of Tea by Chromatographic Methods: A Review

2015 ◽  
Vol 4 (3) ◽  
pp. 56 ◽  
Author(s):  
Alexandr Ya Yashin ◽  
Boris V. Nemzer ◽  
Emilie Combet ◽  
Yakov I. Yashin
Keyword(s):  
Chemical Composition ◽  
Volatile Compounds ◽  
Black Tea ◽  
Storage Conditions ◽  
Organoleptic Evaluation ◽  
Chromatographic Methods ◽  
Tea Quality ◽  
Processing And Storage ◽  
And Storage

<p>Despite the fact that mankind has been drinking tea for more than 5000 years, its chemical composition has been studied only in recent decades. These studies are primarily carried out using chromatographic methods. This review summarizes the latest information regarding the chemical composition of different tea grades by different chromatographic methods, which has not previously been reviewed in the same scope. Over the last 40 years, the qualitative and quantitative analyses of high volatile compounds were determined by GC and GC/MS. The main components responsible for aroma of green and black tea were revealed, and the low volatile compounds basically were determined by HPLC and LC/MS methods. Most studies focusing on the determination of catechins and caffeine in various teas (green, oolong, black and pu-erh) involved HPLC analysis.</p> <p>Knowledge of tea chemical composition helps in assessing its quality on the one hand, and helps to monitor and manage its growing, processing, and storage conditions on the other. In particular, this knowledge has enabled to establish the relationships between the chemical composition of tea and its properties by identifying the tea constituents which determine its aroma and taste. Therefore, assessment of tea quality does not only rely on subjective organoleptic evaluation, but also on objective physical and chemical methods, with extra determination of tea components most beneficial to human health. With this knowledge, the nutritional value of tea may be increased, and tea quality improved by providing via optimization of the growing, processing, and storage conditions.</p>

scholarly journals DETERMINATION OF BTEX IN ENVIRONMENTAL SAMPLES: DEVELOPMENT AND PROTECTION OF TECHNOLOGIES AND ANALYTICAL METHODS

2019 ◽  
Vol 16 (31) ◽  
pp. 431-439
Author(s):  
Helilma de Andréa PINHEIRO ◽  
Ana Paula Mota FERREIRA ◽  
Ismael Carlos Braga ALVES ◽  
Antônio Fernandes SANTOS JÚNIOR ◽  
Raquel Bezerra dos Santos SAWCZUK ◽  
...  
Keyword(s):  
Petroleum Hydrocarbons ◽  
Environmental Samples ◽  
Low Cost ◽  
The United States ◽  
Operational Control ◽  
Toxic Compounds ◽  
Chromatographic Techniques ◽  
Benzene Toluene ◽  
And Storage

The contamination of water and soil by petroleum hydrocarbons is reported quite frequently, mainly due to accidents involving transport and storage of fuels. Among the most toxic compounds the most volatile benzene, toluene, ethylbenzene and xylene (BTEX). Residues of these compounds can cause serious environmental and public health troubles. Thus, more sensitive, selective and low-cost techniques, focused on the analysis and monitoring of these contaminants are being developed in order to establish operational control and to comply with local laws, but the intellectual property of such technologies is still unknown. The present study shows the panorama about patents, thesis and dissertations which have been already published on this theme. Together, the United States and China hold the largest number of patents, and most of thesis/dissertations describe methodologies for BTEX detection in water, although numerous environmental problems caused by oils in the soil had been reported. Also, the methods based on chromatographic techniques stand out in relation to the other techniques. It was possible to verify important advances in the field of sensors, especially the electrochemical ones, in order to solve the analytical gaps.

scholarly journals Design and Build a Multilevel Mace Nutmeg Dryer to Improve the People's Economy

SinkrOn ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 107-112
Author(s):  
Ihsan Ihsan ◽  
Dirja Nur Ilham ◽  
Reza Ade Putra ◽  
Rudi Arif Candra ◽  
Arie Budiansyah
Keyword(s):  
Software Design ◽  
Economic Value ◽  
Research Work ◽  
Test Results ◽  
Drying Process ◽  
Wet Season ◽  
Drying Time ◽  
Agricultural Community ◽  
Design Software

Nutmeg is a source of income for some people in South Aceh, and some types of nutmeg, like mace nutmeg, are of better quality. Mace nutmeg is also an agricultural community with great economic value and benefits for humans, as it can be processed into spices and herbs. A range of products includes nutmeg oil and medicines. The harvesting and drying of mace nutmeg, which is still considered a problem by nutmeg growers, cannot be isolated from the processing of the basic ingredients. The natural process of drying mace nutmeg involves the use of sunshine, which necessitates a considerable drying time. Therefore nutmeg farmers frequently complain of erratic weather, especially during the wet season. The constant rain can cause the mace to rot, causing the nutmeg farming community's revenue to become unstable. Methods and steps of research work starting from the study of literature, determination of design specifications, hardware design, software design, toolmaking, tool testing.Good results were reached with the dryness of the mace nutmeg, which can be adjusted, and without putting into account the weather in the drying process, which is usually done with the heat of the sun, per the results of the testing of the designed tools.The average dryness of mace nutmeg is at a temperature of 45 percent with a time of 4 hours and a capacity of 100 grams; according to the test results of the automatic mace drying machine, it produces 50 grams of dry mace.  

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