DEPARTMENT OF CHEMICAL ENGINEERING

This research endeavor seeks to develop an innovative catalyst for the pyrolysis procedure, transforming waste plastic (polyethylene terephthalate PET) into a liquid fuel source. The objectives include preparation of waste PET and clay specimens, the fabrication of a zeolite catalyst from clay, and the subsequent examination and characterization of this catalyst. The experimental setup entailed weighing 500 g of PET particles and 25 g of zeolite catalyst, purging the system with nitrogen gas to establish an oxygen-free milieu, and commencing pyrolysis at 450°C with a heating gradient of 15°C/min and a reaction duration of 30 min in a diminutive fixed-bed reactor.
The findings indicate the efficacy of calcined clay soil in the pyrolysis of discarded PET containers. Structural analysis revealed specific surface area, bulk density, particle size, and porosity values of 86.10 m²/g, 1.285 g/cm³, <100μm, and 48%, respectively. Spectroscopic analysis underscored a notable composition of calcium oxide in the catalyst, corroborating its catalytic prowess. Furthermore, the catalytic pyrolysis process yielded a greater volume of oil compared to non-catalytic pyrolysis, as exemplified in Table 4.3. The physiochemical attributes of the resultant oil conformed to ASTM standards, with caloric value, flash point, kinematic viscosity, and specific gravity measured at 16.42 kcal/kg, 78°C, 2.80 mm²/s, and 0.8601, respectively.
In conclusion, this study proffers a promising approach to address the issue of plastic waste by converting PET bottles into a valuable liquid fuel source utilizing a novel clay-based catalyst. The developed catalyst exhibits advantageous structural and spectroscopic properties, enhancing the efficiency of the pyrolysis process. Moreover, the resulting fuel meets industry benchmarks, intimating its potential for practical applications in energy production and waste management.

The study investigated the use of palm kernel shells and snail shells in the synthesis of a bio-based bifunctional heterogeneous catalyst. Using impregnation methods, palm kernel shells (PKS) biochar was functionalized with calcined snail shell doped with copper sulphate. The catalytic activity of the resulting catalyst was tested through the simultaneous esterification and transesterification of palm kernel oil (PKO). The characteristics of the catalyst were examined using X-ray diffraction spectroscopy (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray fluorescence (XRF). The results showed that catalyst formulation with 90wt% CaO catalyst and 10 wt% activated PKS biochar generates the greatest biodiesel yield of 93.2%; this was reached with 3 wt% catalyst loading, 12:1 methanol to PKO molar ratio at 60 C within 1 hour and 30 minutes of reaction time. The bifunctional heterogeneous catalyst is chemically stable and can be reused up to five times, producing 72.6% biodiesel in the final cycles. The results show that the biodiesel produced meets the worldwide standards. The use of waste material to create an effective bifunctional catalyst for biodiesel synthesis from palm kernel oil (PKO) has significant commercialization potential in the future.

Biogas is a gas mixture consisting mainly of methane and carbon(IV)oxide resulting from the biological process of anaerobic digestion of various organicmaterials. The percentage of methane in biogas will vary depending on the processconditions and the type of organic matter fermented. This study investigatedtheeffects of thermal and alkaline pretreatment methods on cattle rumen content andincrease the biogas yield. In the course of this study, sodiumhydroxide (NaOH) was the alkali of choice and temperature ranges of 70ºc 80ºc and 90ºc in a BoxBehnken design. Modelling was carried out with using Response Surface Methodology (RSM) which was used for the Analysis of Variance (ANOVA) andmultiple regression analysis of the data obtained. The R2 value of 0.9768for NaOH, contour plots, ANOVA analysis all shows how suitable the RSMmodel is for theexperiment. The optimum conditions necessary for maximum feedstock degradation for the alkaline was examined and it was found by using NaOH atatemperature of 80.171ºC, timed 13.086 minutes and a molar concentration of 2.05M and the degree of degradation is 56.83%.