Application of biosurfactant as a demulsifying and emulsifying agent in the formulation of petrochemical products

Author(s):  
Farzad Raeisi ◽  
Seyyed Mojtaba Mousavi ◽  
Seyyed Alireza Hashemi ◽  
Leila Malekpour ◽  
Sonia Bahrani ◽  
...  
Author(s):  
S.D. Smith ◽  
R.J. Spontak ◽  
D.H. Melik ◽  
S.M. Buehler ◽  
K.M. Kerr ◽  
...  

When blended together, homopolymers A and B will normally macrophase-separate into relatively large (≫1 μm) A-rich and B-rich phases, between which exists poor interfacial adhesion, due to a low entropy of mixing. The size scale of phase separation in such a blend can be reduced, and the extent of interfacial A-B contact and entanglement enhanced, via addition of an emulsifying agent such as an AB diblock copolymer. Diblock copolymers consist of a long sequence of A monomers covalently bonded to a long sequence of B monomers. These materials are surface-active and decrease interfacial tension between immiscible phases much in the same way as do small-molecule surfactants. Previous studies have clearly demonstrated the utility of block copolymers in compatibilizing homopolymer blends and enhancing blend properties such as fracture toughness. It is now recognized that optimization of emulsified ternary blends relies upon design considerations such as sufficient block penetration into a macrophase (to avoid block slip) and prevention of a copolymer multilayer at the A-B interface (to avoid intralayer failure).


1890 ◽  
Vol 29 (748supp) ◽  
pp. 11955-11955
Author(s):  
H. Collier
Keyword(s):  

2021 ◽  
Vol 349 ◽  
pp. 129203
Author(s):  
Yuxing Gao ◽  
Yujie Lei ◽  
Yuehan Wu ◽  
Hongshan Liang ◽  
Jing Li ◽  
...  
Keyword(s):  

2005 ◽  
Vol 41 (2) ◽  
pp. 131-140 ◽  
Author(s):  
A. G. Dedov ◽  
I. I. Moiseev ◽  
A. S. Loktev ◽  
N. T. Kuznetsov ◽  
V. A. Ketsko ◽  
...  

2010 ◽  
Vol 1279 ◽  
Author(s):  
Kusman. Dossumov ◽  
Svetlana. A. Tungatarova

AbstractSupported polyoxide catalysts on the base of Mo and W, as well as natural Kazakhstan's clays were tested in the process of oxidative conversion of propane and propane-butane mixture. The influence of reaction temperature, contact time, composition and percentage of the active component of catalyst were determined. The important petrochemical products - acetone (500-550°) and acetaldehyde (300-350°) were the main liquid products of reaction on natural Kazakhstan's clays and also on clays modified by Mo, Bi, Cr and Ga ions.


Author(s):  
Emmanuel O. Olorunsola ◽  
Stephen O. Majekodunmi

Objective: Afzelia africana gum has been shown to possess surface activity. It is a good alternative to sodium carboxy methylcellulose in terms of suspending properties. This work was aimed at evaluating the emulsifying properties of the gum in liquid paraffin emulsion.Methods: Liquid paraffin emulsions (200 ml each) were prepared with different concentrations (1, 2, 3, 5 and 10 % w/v) of afzelia gum as an emulsifying agent. Similar preparations containing standard acacia gum at corresponding concentrations were also made. Liquid paraffin emulsions (200 ml each) were equally prepared using 60 ml liquid paraffin as the oily phase and 6 g of various combinations of afzelia gum and tween 80 as emulsifier blends. The emulsifier blends were of ratio 1:5, 1:2, 1:1, 2:1 and 5:1. The preparations were assessed for density and viscosity; and then for stability after 5 d of storage.Results: The viscosity of emulsion containing 10 % w/v afzelia gum was 668.90 mPa.s while that of an emulsion containing the same concentration of acacia gum was 23.56 mPa. s. Emulsion containing 3 % w/v afzelia gum (having a creaming index of 16 %) was found to be more stable compared to the emulsion containing 10 % w/v acacia gum (having creaming index of 28 %). The viscosity and stability of emulsions containing emulsifier blends of afzelia gum and tween 80 increased with increase in the proportion of afzelia gum.Conclusion: The gum is suitable for use at a concentration of 3 % w/v as an emulsifier in 30 % v/v liquid paraffin emulsion, and it is about three times better than acacia gum as an emulsifier. It is a good alternative to standard acacia gum for emulsification. 


Author(s):  
Heba S. Elsewedy ◽  
Bandar E. Al-Dhubiab ◽  
Mahmoud A. Mahdy ◽  
Hanan M. Elnahas

One of the widely efficient and noteworthy nanocarriers that could draw a great attention toward pharmaceutical fields is nanoemulsions (NEs). NEs are thermodynamically stable colloidal dispersions composed of two immiscible liquids, oil and water that mixed together using emulsifying agent (surfactant and co-surfactant). It regarded as pharmaceutical dosage form having droplet size within a nanometer range, hence it has extensively considered as carrier for delivering active agents. Such carrier is fabricated in order to overcome some obstacles associated with conventional drug delivery systems especially low bioavailability. The objective of this review is to present an overview about NE and its latest applications in diverse areas such as drug delivery, cosmeceutical and nutraceutical. Clarifications about different mechanisms of NEs development that are frequently used were provided. Correspondingly, popular characterization techniques for NEs such as determination of particle size, polydispersity index (PDI), zeta potential and viscosity were reviewed. Eventually, summary of physical and chemical instability in addition to the regulatory aspects of NE were provided.


1999 ◽  
Vol 276 (6) ◽  
pp. L1037-L1045 ◽  
Author(s):  
Joseph D. Brain ◽  
Ramon M. Molina ◽  
Malcolm M. DeCamp ◽  
Angeline E. Warner

Because mononuclear phagocytes take up perfluorochemical emulsions (PFCE), we examined how prior treatment with PFCE affects the fate of circulating bacteria. Rats were preinjected with three daily intravenous injections of PFCE (2.0 ml/100 g) containing 12.5% (vol/vol) of a 4:1 mixture of F-dimethyl adamantane and F-trimethylbicyclo-nonane, 2.5% (wt/vol) Pluronic F-68 as the emulsifying agent, and 3% (wt/vol) hydroxyethyl starch as the oncotic agent. Pseudomonas aeruginosa or Staphylococcus aureus were injected 4 h after the third PFCE injection. PFCE pretreatment decreased the rate and extent of vascular clearance of P. aeruginosa, with decreased uptake by the liver. Importantly, there were significant decreases in killing of P. aeruginosa in the liver, lungs, spleen, and kidneys of PFCE animals. PFCE did not alter the clearance of S. aureus from the circulation. However, hepatic uptake was reduced, with concomitant increases in lung and kidney uptake. Ultrastructure of Kupffer cells revealed PFCE inclusions and extensive vacuolization. These experiments demonstrate that the clearance kinetics and organ distribution of circulating P. aeruginosa and their subsequent killing are altered by PFCE. Diminished hepatic phagocyte function leads to a decrease in vascular clearance of circulating bacteria, increased uptake in other reticuloendothelial organs, and decreased bactericidal activity versus P. aeruginosa.


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