Evaluation of a novel tripodal diglycolamide for actinide extraction: Solvent extraction and SLM transport studies

2011 ◽  
Vol 375 (1-2) ◽  
pp. 141-149 ◽  
Author(s):  
P.K. Mohapatra ◽  
M. Iqbal ◽  
D.R. Raut ◽  
W. Verboom ◽  
J. Huskens ◽  
...  
2018 ◽  
Vol 14 (1-2) ◽  
pp. 184-187
Author(s):  
Elfi Anis Saati ◽  
Annisa Dyah Pusparini ◽  
Mochammad Wachid ◽  
Sri Winarsih

Red rose consisting of anthocyanin pigment has been used as an antibacterial agent. However, there is no study on the anthocyanin pigment extract from red rose as the antibacterial agent. The effectiveness of the antibacterial agent can be affected by the solvent extraction and the flower shelf life. Here, we report the effects of solvent extraction and red rose (Rosa sp.) shelf life on the antibacterial activity. Red rose concentrated extraction and randomized complete block design factorial was carefully used with factors of long display and solvent extraction. The extraction solvent (P) comprised of water, ethanol, and mixture of water-ethanol (1 : 1), while the red rose shelf life (M) consisted of 0, 2, 4 and 6 days. Moreover, pH, antioxidant activity and minimum bactericidal concentration (MBC) with four variations of concentrated concentration (100%, 50%, 25% and 12.5%) on Escherichia coli, Salmonella thypi, and Pseudomonas sp. were analyzed. After two days of shelf life using water as the solvent for extraction, the antioxidant activity achieved 79% at pH of 2.5. It was also demonstrated that it was able to kill all the investigated bacterias, which were Escherichia coli, Salmonella thypi, and Pseudomonas sp. with concentrated concentrations of 100%, 50% and 25%. When the concentrated concentration was 12.5%, the MBC value was constantly found to be 1.39 × 108 cfu/g for Escherichia coli and 9.53 × 107 cfu/g for Salmonella thypi.


2012 ◽  
Vol 23 (2) ◽  
pp. 149-154
Author(s):  
Ancaelena-Eliza Sterpu ◽  
Anca Iuliana Dumitru ◽  
Mihai-Florinel Popa

AbstractHuge amounts of used lubricating oils from automotive sources are disposed of as a harmful waste into the environment. For this reason, means to recover and reuse these wastes need to be found. Problems arising from acid treatment include environmental problems associated with the disposal of acid sludge and spent earth, low product yield (45-65%) and incomplete removal of metals. The processes of re-refining of used lubricating oils depend greatly on the nature of the oil base stock and on the nature and amount of contaminants in the lubricant resulting from operations. The study was carried out on a sample of 15W40 type used oil collected from one automobile. The re-refining process of used oil consists of dehydration, solvent extraction, solvent stripping and vacuum distillation. This study aims to investigate a process of solvent extraction of an alcohol-ketone mixture as a pre-treatment step followed by vacuum distillation at 5 mmHg. The primary step was conducted before the solvent extraction that involves dehydration to remove the water and fuel contaminants from the used oil by vacuum distillation. The solvent extraction and vacuum distillation steps were used to remove higher molecular weight contaminants. The investigated solvent to oil ratios were 2, 3, 4, 5 and 6. The solvent composition is 25% 2-propanol, 50% 1- butanol and 25% butanone or methyl ethyl ketone (MEK). The percentage of oil recovery for the solvent to oil ratio of 6:1 is further improved, but for the ratio values higher than 6:1, operation was considered economically not feasible. Finally, the re-refined oil properties were compared with the commercial virgin lubricating oil properties.


2014 ◽  
Vol 521 ◽  
pp. 638-643
Author(s):  
Hong Guan Wu ◽  
Hai Feng Li ◽  
Guo Xian Yu

A compounded deacidificant was used for deacidification of domestic Bei-Jiang crude. In this work, its formulation was optimized in detail. Effect of reaction temperature, time and the ratio to crude oil was examined. Acceleration by using ultrasonic irritation in deacidification process was investigated. Our results revealed a deacificant composed of ethylene glycol as neutralization agent and cyclohexylamine as extraction solvent not only provided an excellent deacidificcation extent, but also no emulsion problem appeared. 30% cyclohexylamine-containing ethylene glycol solution has the best performance. Deacidification extent reached 85% and higher at a solvent and oil weight ratio of 15%.Ultrasonic wave played an accerleration role, resulting in a shorter reaction time. Naphthenic acids and solvent components were recovered by using vacuum distillation.The recovery rate for solvent components were 99.3% for ethylene and 96.6% for cyclohexylamine respectively. The purity of recovered naphthenic acids was rather high, reaching a acid value of 167.


Processes ◽  
2020 ◽  
Vol 8 (7) ◽  
pp. 803
Author(s):  
Maja Repajić ◽  
Ena Cegledi ◽  
Valentina Kruk ◽  
Sandra Pedisić ◽  
Fırat Çınar ◽  
...  

This study aimed to investigate the performance of accelerated solvent extraction (ASE) as a green approach for the recovery of polyphenols and pigments from wild nettle leaves (NL). ASE was operated at different temperatures (20, 50, 80 and 110 °C), static times (5 and 10 min) and cycle numbers (1–4) using ethanol (96%) as an extraction solvent. In order to compare the efficiency of ASE, ultrasound assisted extraction (UAE) at 80 °C for 30 min was performed as a referent. Polyphenol and pigment analyses were carried out by HPLC and antioxidant capacity was assessed by ORAC. Seven polyphenols from subclasses of hydroxycinnamic acids and flavonoids, along with chlorophylls a and b and their derivatives and six carotenoids and their derivatives were identified and quantified. Chlorogenic acid was the most abundant polyphenol and chlorophyll a represented the dominant pigment. ASE conditions at 110 °C/10 min/3 or 4 cycles proved to be the optimal for achieving the highest yields of analyzed compounds. In comparison with UAE, ASE showed better performance in terms of yields and antioxidants recovery, hence delivering extract with 60% higher antioxidant capacity. Finally, the potential of NL as a functional ingredient from natural sources can be successfully accessed by ASE.


2011 ◽  
Vol 2011 ◽  
pp. 1-25 ◽  
Author(s):  
Hanifa Taher ◽  
Sulaiman Al-Zuhair ◽  
Ali H. Al-Marzouqi ◽  
Yousef Haik ◽  
Mohammed M. Farid

Biodiesel is considered a promising replacement to petroleum-derived diesel. Using oils extracted from agricultural crops competes with their use as food and cannot realistically satisfy the global demand of diesel-fuel requirements. On the other hand, microalgae, which have a much higher oil yield per hectare, compared to oil crops, appear to be a source that has the potential to completely replace fossil diesel. Microalgae oil extraction is a major step in the overall biodiesel production process. Recently, supercritical carbon dioxide (SC-CO2) has been proposed to replace conventional solvent extraction techniques because it is nontoxic, nonhazardous, chemically stable, and inexpensive. It uses environmentally acceptable solvent, which can easily be separated from the products. In addition, the use of SC-CO2 as a reaction media has also been proposed to eliminate the inhibition limitations that encounter biodiesel production reaction using immobilized enzyme as a catalyst. Furthermore, using SC-CO2 allows easy separation of the product. In this paper, conventional biodiesel production with first generation feedstock, using chemical catalysts and solvent-extraction, is compared to new technologies with an emphasis on using microalgae, immobilized lipase, and SC-CO2 as an extraction solvent and reaction media.


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