- Synthesis of isobutyl propionate using immobilized lipase in a solvent free system: Optimization and kinetic studies
-
Isobutyl propionate is widely used in food and beverage industries as a rum flavor. This work presents the optimization and kinetic aspects of synthesis of isobutyl propionate by esterification of propionic acid with isobutyl alcohol using immobilized lipase Novozym 435 in a solvent free system (SFS). Process parameters such as reaction time, temperature, enzyme loading, speed of agitation, water concentration and acid to alcohol molar ratio were optimized to achieve maximum conversion. Higher conversion of 92.52% was obtained with the reaction conditions such as: temperature 40 C, enzyme loading 5% w/w, acid to alcohol molar ratio 1:3, time 10 h and stirring speed of 300 rpm. The bisubstrate kinetic models of the enzyme catalyzed reactions namely Ordered Bi-Bi, Random Bi-Bi and Ping-Pong Bi-Bi were applied to determine the initial rates and correlated with the experimental findings. Ping-Pong Bi-Bi model with substrate inhibition by both acid and alcohol gives the best fit with parameter values as Vmax = 0.5 Mol/min/g catalyst, KA = 0.631 M, KB = 0.003 M, KiA = 0.0042 M and KiB = 0.1539 M for the concentration ranges of 2.25-10.21 M for propionic acid and 2.55-9.01 M for iso-butanol. The immobilized lipase could be reused for seven times with the % conversion of acid reaching to 83%; signifies that still it can be reused for several more times. SFS is the added benefit to produce such commercially valuable flavor ester.
- Kuperkar, Vishakha V.,Lade, Vikesh G.,Prakash, Arushi,Rathod, Virendra K.
-
-
Read Online
- Method for synthesizing propionate through ester-ester exchange path
-
The invention provides a method for synthesizing propionate through an ester-ester exchange path and relates to a method for synthesizing the propionate. According to the method, reaction raw materials include, but are not limited to ethyl formate, propyl formate, butyl formate, ethyl acetate, propyl acetate, butyl acetate and the like; the method for synthesizing the propionate through an ester exchange one-step method is adopted. A catalyst comprises alkaline materials including ionic liquid, soluble strong base, solid base and the like respectively; the catalyst has the advantages of high catalysis efficiency and no pollution. By taking methyl propionate and ethyl acetate reaction as an example, KOH is used as the catalyst, the mol ratio of the raw materials is 1 to 1, the reaction temperature is 60 DEG C and the reaction time is 5 min; the conversion ratios of the methyl propionate and the ethyl acetate can reach 70 percent or more; products comprise ethyl propionate and the methylacetate. The whole reaction path has the characteristics of short synthetic route, simple technological flow and high yield and the catalyst is stable, does not become inactive and can be repeatedlyutilized.
- -
-
Paragraph 0030-0031
(2019/04/04)
-
- Carboxyl activation of 2-mercapto-4,6-dimethylpyrimidine through n-acyl-4,6-dimethylpyrimidine-2-thione: A chemical and spectrophotometric investigation
-
2-Mercapto-4,6-dimethylpyrimidine, as effective carboxyl activating group, has been successfully proved by converting it into respective acyl derivatives and the subsequent conversion to the amides and esters respectively using amines, amino alcohols and alcohols. The aminolysis and esterification were monitored chemically and spectrophotometrically. This paved way to establish that the above mercaptopyrimidine derivative is an efficient carboxyl activating group applicable in solid phase peptide synthesis.
- Rajan
-
p. 287 - 291
(2015/01/30)
-
- Highly regioselective and rapid hydroformylation of alkyl acrylates catalyzed by a rhodium complex with a tetraphosphorus ligand
-
Alkyl acrylates have been hydroformylated to the linear aldehydes with high regioselectivity (linear/branch > 99/1) and extraordinarily high average turnover frequencies (up to 5400 h-1) by using a rhodium complex with a tetraphosphorus ligand.
- Yu, Shichao,Chie, Yu-Ming,Zhang, Xumu
-
experimental part
p. 537 - 540
(2009/11/30)
-
- Solid acids in liquid phase esterification
-
Catalytic activity of different protonated zeolites such as HY, Hβ, HZSM5 and sulfated oxides such as SO42-/Al 2O3, SO42-/SiO2, SO 42-/ZrO2 in the esterification of propionic acid with various alcohols (C1-C5) over solid acids as catalysts has been investigated. The catalysts have been characterized for their total surface acidity, BET surface area and sulfur content in sulfated catalysts. Catalytic activity studies have been conducted in liquid phase under refluxing conditions. A systematic study has been made to find out the effects of nature of alcohols, amount of the catalyst and the duration of reaction in the synthesis of propionate esters. Product analysis has been done quantitatively by gas chromatography and qualitatively by GC-MS. All the catalysts have been found to be active towards the formation of propionate esters as the major reaction product. A good correlation between the concentration of acid sites and the catalytic activity of the catalysts has been observed.
- Nagaraju,Mohamed Shamshuddin
-
p. 1165 - 1170
(2007/10/03)
-
- Catalytic esterifications of carboxylic acids and alcohols by sodium bisulfate monohydrate
-
The efficient esterification of primary and secondary alcohols with aliphatic carboxylic acids in the presence of a catalytic amount of sodium bisulfate monohydrate to afford the corresponding esters in high yields.
- Li, Yi-Qun
-
p. 3901 - 3903
(2007/10/03)
-
- Preparation of salicylic acid resin supported FeCl3 lewis acid catalyst and its application in organic synthesis
-
The catalytic effects of salicylic acid resin supported FeCl3 catalyst on the esterification of alcohol and carboxylic acid and on the acetalization (ketal formation) of aldehyde (ketone) and alcohol have been investigated.This catalyst is convenient to use, noncorrosive, easy to be separated from reactants and can be repeatedly used.
- Huirong, Yang,Yingde, Li Bina Cui
-
p. 1233 - 1238
(2007/10/03)
-
- A study on synthesis of esters by superacid resin catalysts
-
Superacid resin as catalyst, instead of the strong acid cation exchange resin and sulfuric acid was used to synthesis n-butyl lactate. Some factors affection reaction, such as time, moles ratio of reactants and catalyst amount were studied. Results made known that time was shorten very much. Under our optimum conditions the ester yield was over 99.5%. In the other hand, superacid resin as catalyst was used to synthesis other esters, had result of raise ester yield and shorten the time of esterification.
- Yang,Li,Fang
-
p. 3269 - 3275
(2007/10/02)
-