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INDUSTRIAL ORGANIC SOLVENTS
Published in Nicholas P. Cheremisinoff, Industrial Solvents Handbook, Revised And Expanded, 2003
Ethanol bums in air with a blue flame, forming carbon dioxide and water. It reacts with active metals to form the metal ethoxide and hydrogen, e.g., with sodium it forms sodium ethoxide. It reacts with certain acids to form esters, e.g., with acetic acid it forms ethyl acetate. It can be oxidized to form acetic acid and acetaldehyde. It can be dehydrated to form diethyl ether or, at higher temperatures, ethylene.
Equilibrium and hysteresis formation of water vapor adsorption on microporous adsorbents: Effect of adsorbent properties and temperature
Published in Journal of the Air & Waste Management Association, 2022
Lijuan Jia, Ben Niu, Xiaoxia Jing, Yangfang Wu
HPA were prepared via post-crosslinking of low-crosslinked macroporouspoly (styrene-divinylbenzene) (Jia, Yao, and Ma 2017). GAC and ACF were supplied by MeadWestvaco Company (Richmond, USA) and Jiangsu Sutong Carbon Fiber Co. Ltd. (Jiangsu, China) separately. The porous texture of HPA, ACF and GAC were determined by N2 adsorption-desorption isotherms data at 77 K, using an adsorption analyzer ASAP 2020 (Micromeritics Instrument Co., USA). Brunauer–Emmett–Teller (BET), Dubinin–Astakhov(DA), and Barrett–Joyner–Halenda(BJH) equation were applied to calculate their specific surface area (SBET), micropore volume (Vmicro) and mesopore volume (Vmeso). The functional groups of carbon–oxygen complexes on adsorbent were measured according to Boehm titration (Boehm 1994). In detail, the amount of various acidic sites were calculated by assuming that sodium bicarbonate only neutralizes the carboxylic group, sodium carbonate reacts with carboxylic and lactonic groups, sodium hydroxide neutralizes carboxylic, lactonic and phenolic groups, and sodium ethoxide neutralizes carboxyl, lactone, phenolic and carbonyl groups. The physical-chemical properties of three adsorbents were listed in Table 1.
Catalysts used in biodiesel production: a review
Published in Biofuels, 2021
Sodium hydroxide (NaOH), potassium hydroxide (KOH), sodium methoxide (NaOCH3), potassium methoxide (KOCH3), sodium ethoxide (NaOC2H5), sodium peroxide (Na2O2) and sodium butoxide (C4H9NaO) are the most commonly used homogeneous alkaline catalysts in the transesterification of edible oil [16–18]. The formation of water as the result of transesterification with potassium hydroxide and sodium hydroxide reduces the performance of biodiesel. However, transesterification with sodium methoxide and potassium methoxide leads to higher performance in this area. The latter is due to the fact that water is not formed as a byproduct during the reaction [18]. Homogeneous alkaline catalysts fit clean oils with FFA values of less than 0.5% because high levels of FFA lead to soap formation and pose separation problems [4,19,20]. Some researchers have reported that alkaline catalysts may tolerate high levels of FFA. However, it is clear that the level of FFA in the oil for the alkaline catalyst in the transesterification reaction should be held between 0.5 wt.% and 2 wt.% (Table 1).
Synthesis, structure and reactivity of some chiral benzylthio alcohols, 1,3-oxathiolanes and their S-oxides
Published in Journal of Sulfur Chemistry, 2020
R. Alan Aitken, Philip Lightfoot, Andrew W. Thomas
Our synthesis started by diazotization of the amino acids leucine, valine and isoleucine bearing bulky alkyl side chains in the presence of 3–6 equivalents of potassium bromide [4] to afford the α-bromo acids 1–3 (Scheme 1). These showed good agreement of boiling point and optical rotation with literature values. An attempt was then made to introduce sulfur by addition of potassium ethyl xanthate to a solution of the α-bromo acids in aqueous sodium carbonate. This proved to be highly effective in the case of bromo acid 1 to afford the previously unknown derivative 4 in almost quantitative yield. However, as previously documented [5], the corresponding reaction with the more sterically hindered bromo acids 2 and 3 failed. Direct reduction of the xanthate 4 with lithium aluminium hydride gave a mixture of mercapto alcohol and mercapto acid in both THF and diethyl ether, so the acid group was first converted into the ethyl ester to give 5, which was then efficiently reduced to afford the mercapto alcohol 6 as an intensely unpleasant smelling oil. To give the first target benzylthio alcohol 7, this was S-benzylated by treatment with sodium ethoxide in ethanol followed by benzyl bromide.