Synthesis and evaluation of some new demulsifiers based on bisphenols for treating water-in-crude oil emulsions

The present paper endeavors to synthesize nine types of demulsifiers based on bisphenols (bisphenol A (BA), bisphenol AC (BAC) and bisphenol CH (BCH)) having different ethylene oxide units (n = 27, 34, 45) namely; E (x + y) (where E represents BA, BCH or BAC and (x + y) which represents the ethylene oxide units (27, 34, 45)). The chemical structures of the prepared demulsifier were elucidated using FT-IR and 1H NMR spectra. Effect of the chemical structure (hydrophobic and ethoxylated degree of hydrophilic parts) and the mechanism of demulsification process was investigated. The data were discussed on the light of the chemical structure of the demulsifiers and the factors, effecting the demulsification process. The efficiency of these demulsifiers was tested on water-in-oil emulsions (w/o) at different concentrations (100, 200 and 300 ppm), 7.4% asphaltene content and 30%, 50% and 70% water content. From the obtained data the best demulsifier was E(34)BA which shows 100% demulsification after 58 min at 30% water content and 300 ppm of the demulsifier

Adsorption of Polymeric Additives Based on Vinyl Acetate Copolymers as Wax Dispersant and Its Relevance to Polymer Crystallization Mechanisms

The present work has main target to study the effect of additives molecular weight and composition on the flow characteristics of wax crude oil at low temperature below pour point temperature. In this respect, maleic anhydride ester-co-vinyl acetate copolymers with varied monomers feed ratios and different alkyl ester lengths, namely, dodecyl, stearyl, and behenyl alkyl chains, were prepared. These polymeric materials were characterized by FTIR, 1HNMR, and GPC. The performance of these additives as pour point depressants and flow improver for Egyptian waxy crude oil was evaluated through measurements of pour point and rheological parameters (viscosity and yield stress). It was observed that stearyl maleate-vinyl acetate copolymer with 1 : 2 feed ratio shows the best efficiency as pour point depressant even at low concentration while octadecyl maleate-vinyl acetate copolymers with 2 : 1 feed ratio are effective as flow improver

A preliminary study on liquid crystalline epoxy curatives from natural abietic acid

Abietic acid was used for preparing two thermotropic liquid crystalline curing agents with different mesogens (LCC1 and LCC2). The chemical structure of the synthesized LCCs was investigated by FTIR and 1HNMR spectroscopic techniques. Their LC phase transition temperatures and texture were identified by differential scanning calorimeter (DSC) and polarized optical microscope (POM), respectively. Both LCCs show nematic droplet texture -as revealed by POM micrographs- but different isotropization temperatures. Eventually, they were used for producing epoxy coatings using a multifunctional abietic acid based epoxy resin; prepared in our previous study. Cured coats were evaluated by standard coating testing and compared with a commercial curing agent. Dynamic mechanical (DMA) and thermogravimetric (TGA) analyses show that the fully bio-based cured epoxies by either LCCs possess high glass transition temperature (Tg), high modulus (G′) and improved thermal stability. Keywords: Abietic acid, Epoxy, Liquid crystal, Dynamic mechanical analysis, Thermogravimetric analysi