Research On Synthesis And Corrosion Performance Of The1,3-dioxolan-4-yl Benzimidazole Derivatives

At present,the hydrolysis procedure to maintain higher fatty acids and glycerol is the main way to recycle gutter oil,which could be then transferred into soap,industrial raw materials,non-phosphorus laundry powder and biodiesel,by which glycerol as a by-product is not fully utilized,so it is of great importance to study glycerol with a high added value conversion,fully recycling the gutter oil and producing economic benefits as well as being of far-reaching implications on scientific research simultaneously.In this paper,the by-product glycerol was taken as the raw material to get glycerol formal,which was then transferred into 4-carboxyl-1,3-dioxolane under the catalysis of 2,2,6,6-Tetramethylpiperidinooxy(TEMPO)by reacting with sodium hypochlorite,then three kinds of diamox heterocyclic pentyl benzomidazole derivatives corrosion inhibitors were obtained after the acylation-cyclization of the product with o-phenylendiamine,n-methylo-benzene diamine hydrochloride and N-phenyl o-phenylenediamine,respectively,named as 2-(1,3-dioxolan-4-yl)benzimidazole(OBCI),1-methyl-2-(1,3-dioxolan-4-yl)benzimidazole(MBCI)and 1-phenyl-2-(1,3-dioxolan-4-yl)benzimidazole(PBCI),respectively.The optimum conditions for synthesis of 4-carboxyl-1,3-dioxolane and three kinds of corrosion inhibitors were selected through orthogonal design experiment.Besides,IR spectrum,UV spectrum and NMR spectrum were taken to characterize the structure of the three synthesized products.The results of spectra showed that the 4-carboxyl-1,3-dioxolane and three corrosion inhibitors were synthesized successfully.The static weight loss experiment showed that three corrosion inhibitors had good effect for Q235 in 5% HCl,and the optimal concentration of inhibitors were 100mg/L for OBCI,60 mg/L for MBCI and 60 mg/L for PBCI,reaching inhibition rates of 98.04%,96.28%,97.38% under which,respectively.The contrast test approved that corrosion inhibition effects of the products were comparable to those of the selected commercial ones.The results of electrochemical test(polarization curves and AC impedance method)corresponded well with what from the static weight loss experiment,indicating that OBCI was an anti-anode-based hybrid corrosion inhibitor,and MBCI and PBCI were both mixed-type corrosion inhibitor with the main inhibition of the cathode.The SEM images explained that three corrosion inhibitors and the commercial one can protect the metal by forming an adsorbent membrane in the surface of which,attesting as the adsorbent type of the inhibitors.