scholarly journals Study on Phase Transfer Catalyst Used in the Synthesis of Sodium Isobutyl Xanthate

Minerals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 850
Author(s):  
Zhijun Ma ◽  
Liang Cheng ◽  
Xingyuan Weng ◽  
Ye Gao ◽  
Jiuxing Huang

Xanthates are by far the most widely used collectors in the froth flotation beneficiation of sulfide ores. However, the xanthate production process suffers from low yield, low productivity, long reaction time and environmental pollution. To address these issues, an effective method was developed for the synthesis of xanthates using phase transfer catalyst. Sodium isobutyl xanthate was synthesized from isobutyl alcohol ((CH3)2CHCH2OH), sodium hydroxide (NaOH) and carbon disulfide (CS2) with dichloromethane (CH2Cl2) as solvent and cetyltrimethylammonium bromide (CTAB), cetyltrimethylammonium chloride (CTAC), tetrabutylammonium bromide (TBAB) and tetrabutylammonium chloride (TBAC) as phase transfer catalyst. The compound was characterized by elemental analysis, infrared spectrum, 1H NMR and 13C NMR. The influencing factors on the content and yield of sodium isobutyl xanthate including phase transfer catalyst type, phase transfer catalyst dosage and reaction time were studied by single-factor experiments. The influencing factors on the product purity and yield including reaction temperature, solvent volume, material ratio and rotating speed were studied by orthogonal experiments. The results showed that when the amount of TBAC was 3.0%malcohol, the reaction temperature was 35 °C, the solvent volume was 3.5 Valcohol, the rotating speed was 180 rpm, the reaction time was 4 h and the material ratio was n[(CH3)2CHCH2OH]:n(NaOH):n(CS2) = 1:1:1.10, the product yield could be up to 86.66% and the product purity reached 82.56%.

2014 ◽  
Vol 936 ◽  
pp. 1017-1021
Author(s):  
Pan Chen ◽  
Jin Cheng Wang

Na-MMT was modified with quaternary phosphonium salts, tetramethylolphosphonium chloride (THPC), via ion-exchange reactions, in acid conditions. Different factors such as reaction time , reaction temperature, the types of solvent, and CEC ratios, were investigated using orthogonal test. Results showed that the best combination of these four factors were A1B3C1D1, that is, the type of the solvent was acetone and water (1:1), reaction time was 3h, CEC ratio was 1:1, and the reaction temperature was 80°C.


2017 ◽  
Vol 21 (07n08) ◽  
pp. 476-492 ◽  
Author(s):  
Toshiyuki Akabane ◽  
Kazuchika Ohta ◽  
Tokihiro Takizawa ◽  
Takehiro Matsuse ◽  
Mutsumi Kimura

The most difficult problem on syntheses of the phthalocyanine-based liquid crystals is the long reaction time. In order to shorten the reaction time, we have developed novel Methods A, B and D, for the syntheses of phthalocyanine-based liquid crystals by using microwave heating and/or adding a phase transfer catalysis of Aliquat 336. A series of phthalocyanine derivatives C[Formula: see text]PcZn(1) ([Formula: see text] 10, 12, 14, 16 and 18: a, b, c and e) could be successfully synthesized in a dramatically short reaction time of 30–60 min using Methods A and B by microwave heating. On the other hand, anothor series of the derivatives C[Formula: see text](OH)PcZn (2a–2e) could not be synthesized by microwave heating. Therefore, all these derivatives were synthesized using conventional Method C by oil bath heating, but the reaction took a very long time (22.5–88 h). To shorten the reaction time, we have developed Method D by oil bath heating with adding a phase transfer catalyst of Aliquat 336. In this method, we successfully shortened the reaction time from 88 h to 3 h for the synthesis of the derivative 2a. Thus, the reaction time for oil bath heating can be also greatly shortened by adding the phase transfer catalyst of Aliquat 336. Furthermore, we have established from POM, DSC and temperature-dependent X-ray diffraction measurements that the derivative C[Formula: see text]PcZn (1a) shows a very rare pseudohexagonal columnar (Col[Formula: see text] phase, and that the derivatives C[Formula: see text]PcZn (1b–1e) and C[Formula: see text](OH)PcZn (2b–2e) exhibit spontaneous perfect homeotropic alignment in a large area between two glass plates in their Col[Formula: see text] phases.


2012 ◽  
Vol 460 ◽  
pp. 275-278
Author(s):  
Jian Zhang ◽  
Xuan Jun Wang

The decoloration method experiment on ZSO was studied. The different influencing factors on reaction were investigated by single test, such as content of peroxide, reaction temperature, and reaction time. The results of orthogonal test showed that the dominated sequence of influencing on chroma value was content of peroxide, and then was for reaction temperature, the last was reaction time. The optimal combination proved was A2B2C2. On this condition, the chroma value of ZSO could be reduced to 1.45, it fully meets the requirement of industrial application.


2013 ◽  
Vol 781-784 ◽  
pp. 276-279
Author(s):  
Yu Hang Zhao ◽  
Li Cui ◽  
Da Zhi Wang ◽  
Tong Kuan Xu ◽  
Yong Peng Li

Butanone 1,2-propanediol ketal was synthesized by butanone and 1,2-propanediol as raw materials and sulfamic acid as catalyst. The effects of the mole ratio of raw materials agent, the dosage of the water-carrying agent and catalyst, reaction time on the product yield were discussed separately. Experimental results showed that sulfamic acid was a suitable catalyst for synthesizing of butanone 1,2-propanediol ketal. And the optimal reaction conditions are as follows: the mole ratio of butanone to 1,2-propanediol is 1:1.5, the amount of the catalyst is 2.2%, the water-carrying agent is 25ml, the reaction temperature is 358-378K and reaction time 3h. In this condition, the yield of production could reach 93.8%.


2012 ◽  
Vol 624 ◽  
pp. 252-255 ◽  
Author(s):  
Xiao Zhao ◽  
Qi Song ◽  
Hai Lin ◽  
Yan Ling Wang ◽  
Zeng Bao Wang ◽  
...  

A retarded zirconium cross-linking agent ECA-1 was prepared by using zirconium oxychloride, lactic acid, xylitol, and so on, then we got a high-temperature delayed cross-linking acid with cross-linking agent ECA-1 added to EVA-180 gelling acid, cross-linked acid performance and its influencing factors were discussed in details, such as reaction conditions of crosslinker, concentrations of crosslinker and thickener, and so on. The results showed that the obtained cross-linked acid had good temperature-tolerate and shear-tolerate properties when the mass ratio of zirconium oxychloride, lactic acid and xylitol is 1:1.25:0.0208 , the reaction temperature is 50~55°C, the reaction time is 4 hours, the delayed cross-linking time of acid system can be adjusted by changing the dosage of crosslinker and thickener.


2013 ◽  
Vol 826 ◽  
pp. 233-236
Author(s):  
Rui Mu ◽  
Cui Hua Ji

This study synthesized silicon emulsions by emulsion polymerization, mainly focused on how influencing factors including catalyst, emulsifier, reaction temperature and synthesis process could affect product conversion rate, appearance and molecular weight. The result showed that the conversion rate of the first 2 hours increased rapidly and became stable afterwards. Molecular weight increment was proportional to the extension of the reaction time. The silicon emulsions could achieve high convention rate and stability while applying 5% catalyst DBSA and 3% emulsifier (OP-10: SDS = 1:2) of Octmethyl cyclotetrasiloxane(D4) under an reaction temperature of 80 °C.


Author(s):  
Dirgha Raj Joshi ◽  
Nisha Adhikari

The chemistry of salt is of great importance due to its immense potential from the daily life use to the synthetic chemistry like as workup material, as reagents, as phase transfer catalyst, as acid, as base, as catalyst, as agents for asymmetric synthesis, for some specific reaction transformation, to increase yield, decrease reaction time, ecofriendly synthesis, handling easiness and many more. This review summarizes the overall basic background of salts like how it is formed, nature of salt, generalized application of salts in daily life to synthetic chemistry, its application on other diverse fields, and list of individual categories of major commercially available salts with some structure. Besides having a lot of information on the internet about salts, this review tries to focus on a generalized overview that could be helpful for all to understand salt chemistry.


2012 ◽  
Vol 550-553 ◽  
pp. 400-403 ◽  
Author(s):  
Xue Nan Sun ◽  
Li Cui ◽  
Tong Kuan Xu ◽  
Da Zhi Wang

Benzaldehyde 1, 2-propanediol acetal was synthesized from benzaldehyde and 1, 2-propanediol in the presence of ionic liquid [HMIM]HSO4. The effect of the amount of catalyst, reaction time, reaction temperature, and the molar ratio of raw materials agent on the product yield was investigated respectively. Experimental results demonstrate that ionic liquid [HMIM]HSO4is a good catalyst for preparation of benzaldehyde 1, 2-propanediol acetal. Results showed the optimal reaction conditions are as follows: the mole ratio of benzaldehyde to 1, 2-propanediol is 1:1.3, the amount of catalyst is 3.0g, the reaction temperature is 343K, and the reaction time is 4h. The achieved yield of acetal is 78. 7%.


2010 ◽  
Vol 28 (11) ◽  
pp. 1140-1146 ◽  
Author(s):  
F. T. Li ◽  
D. S. Zhao ◽  
R. H. Liu ◽  
Z. J. Jin ◽  
Z. M. Sun

2010 ◽  
Vol 63 (11) ◽  
pp. 1582 ◽  
Author(s):  
Tamás Patonay ◽  
Attila Vasas ◽  
Attila Kiss-Szikszai ◽  
Artur M. S. Silva ◽  
José A. S. Cavaleiro

The usefulness of the Heck reaction in the field of chromones has been demonstrated. Bromochromones with the halogen atom in their rings A and B were reacted with various terminal alkenes to give hitherto unknown alkenyl‐substituted chromones. Reactivity of the substrates was found to markedly depend on the position of the bromine atom. Under phosphine‐free conditions using a phase‐transfer catalyst additive (tetrabutylammonium bromide), shorter reaction periods and usually higher yields were obtained.


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