Preparation and Characterization of Oligomer from Recycled PET and Evaluated as a Corrosion Inhibitor for C-Steel Material in 0.1 M HCl

Abstract

Polyethylene terephthalate waste (PET) was depolymerized by thiodiglycol into thioglycolyzed product. The product was characterized by FTIR and 1 HNMR spectroscopy and the thermal properties (TGA, DTA) showed that the prepared compound was thermally stable until 250˚C. The efficiency of the prepared corrosion inhibitor for carbon steel was measured by using acid media (0.1 HCl) as corrosive environment and the inhibitor concentration was (0, 10, 20, 30, 40 and 50 ppm). The electrochemical technique used Tafel plot to measure the efficiency of inhibitor. Factors effect on the rate of corrosion like temperature (298, 308, 318, 328 K) and concentration (10,20,30,40, 50 ppm) of inhibitor were studied. From the obtained results many factors were calculated that determined the efficiency of the inhibitor like corrosion rate, charge transfer resistance and inhibitor efficiency. It was observed that the corrosion rate and charge transfer of the carbon steel for the inhibitor increase with increase of temperature and decrease with increase of the inhibitor concentration in the same temperature. The results showed that the inhibitor had high inhibition in reducing the corrosion rate. The inhibition efficiency (% IE) reached 97.1% for the 40 ppm concentration at 308 K.

Back-to-monomer recycling of polycondensation polymers: opportunities for chemicals and enzymes

“…The solvent thiodiglycol in combination with zinc acetate gave bis (2-(2-hydroxyethyl thio-ethyl terephthalate)) as a product. 61 Metal oxides like ZnO, Co 3 O 4 , Mn 3 O 4 , and mixed metal oxides like ZnMn 2 O 4 , CoMn 2 O 4 , and ZnCo 2 O 4 were also employed as catalysts for the depolymerisation of PET plastics. 14,62 Among these, it is remarkable to mention that the monomer BHET can be obtained in up to 70% yield when using zinc acetate and EG as solvent.…”

Preparation, characterization, and evaluation of polymeric resin (BHMET) from the reaction of malic anhydride with recycled PET as a corrosion inhibitor for Csteel in HCl

“…Temperature of the reaction mixture was between 160-180 o C for 12 h, then the reaction mixture was kept at 140 o C for 3 h, then allowed to cool to room temperature. With vigorous agitation distilled water in excess to the reaction mixture to allow the black liquid viscous compound oligomer of Bis(2-((2hydroxyethyl) thio)ethyl terephthalate (BHET) to precipitate (14) . In a three neck round bottom (250 ml) attached with mechanical stirrer and thermometer (5.7gm) of (BHET) compound was added and heated for (15 min.)…”

Temperature Effect on the Corrosion Inhibition of Carbon Steel by Polymeric Ionic Liquids in Acid Medium

“…The temperature effect of polymeric CIs has been analyzed by different authors such as Alaoui et al [ 21 ], who suggested that the IE behavior with respect to the medium temperature is associated with the adsorption type change that presents a polymer; in this way, the increase in the IE is related to a chemisorption process that is favored by a temperature increase. In contrast, Gowraraju et al [ 23 ], Charitha et al [ 24 ] and Yasir et al [ 25 ] observed that an IE decrease as the temperature increases can be explained by a fast adsorption-desorption process and by the decomposition and/or reordering of inhibiting molecules led by a prevailing physisorption process. An implicit variable in the temperature effect on corrosion inhibition processes is the activation energy ( E a ).…”

“…Table 1 shows some studies performed with polymeric CIs and their behavior as a function of temperature. Different types of polymers have been evaluated as CIs at different temperatures: PILs [ 19 , 20 ], synthetic polymers [ 21 ], biomacromolecules [ 22 ], carbohydrates [ 23 , 24 ], recycled PET oligomers [ 25 ] and triblock copolymers [ 26 , 27 ]. The temperature effect of polymeric CIs has been analyzed by different authors such as Alaoui et al [ 21 ], who suggested that the IE behavior with respect to the medium temperature is associated with the adsorption type change that presents a polymer; in this way, the increase in the IE is related to a chemisorption process that is favored by a temperature increase.…”

“…An implicit variable in the temperature effect on corrosion inhibition processes is the activation energy ( E a ). Chauhan et al [ 22 ], Yasir et al [ 25 ] and Kumar et al [ 26 , 27 ] stated that a high E a value in the presence of a CI suggests the formation of a physical barrier attributed to the interaction between inhibiting molecules and the active sites of a metallic surface promoted by the adsorption process of heteroatoms, cyclic rings and functional groups that increase the thickness of the electrical double layer for the formation of an inhibiting film that diminishes the metal corrosion rate.…”