Transformation of paraffin and olefin hydrocarbons on the modified on the zeolite-containing cracking catalyst

As a catalyst for studying the conversion of hydrocarbons contained in catalytic cracking gases, a modified Ni, Co, Cr industrial OMNIKAT-210P zeolite-containing catalyst was used. The purpose of the research is to obtain a high-octane component of gasoline. The deposition of metals was carried out on nano-sized particles of a zeolite-containing catalyst. Particle size was at the level of (5÷10)·10–9 m. The particle size allows you to evenly apply the metals Ni, Cr, Co on the surface of the nanoparticles. Then the particles are molded in the form of balls with a size of 2–3 mm and subjected to drying (120 °С) and calcining 450–500 °С. The yield of liquid products is at the level of 48.3–30.3 % of the mass.

Upgrading Crude Biodiesel dari Minyak Goreng Bekas menggunakan Katalis H-Zeolit

Crude biodiesel hasil transesterifikasi minyak goreng bekas dapat ditingkatkan kualitasnya melalui proses catalytic cracking menggunakan zeolit alam. Penelitian ini bertujuan untuk menentukan kondisi optimum proses catalytic cracking dan sifat fisika dan kimia biofuel yang dihasilkan. Reaksi dijalankan dalam reaktor dengan memvariasikan waktu (1, 2 dan 3 jam), konsentrasi katalis (3, 5 dan 7 %), ukuran partikel katalis (180, 250 dan 630μm) dan suhu reaksi (325, 350 dan 375°C). Kondisi optimum proses catalytic cracking crude biodiesel didapatkan pada : waktu 3 jam, konsentrasi katalis 7%, ukuran partikel katalis 180 μm dan suhu reaksi 375°C. Biofuel yang dihasilkan mengandung 6,26% fraksi bensin(C5-C11); 17,6% kerosin (C12-C15), 47,73% biodiesel (C16-C20) dan asam lemak 28,4%. Analisis sifat fisik menunjukan densitas 0,9631g/mL, titik tuang 12°C, titik nyala 49°C dan angka oktan 72,6. Kata kunci: catalytic cracking, crude biodiesel, angka oktan, biofuel. Crude biodiesel from transesterification of used cooking oil can be improved in quality through catalytic cracking using natural zeolite. This study aims to determine the optimum conditions for catalytic cracking and the physical and chemical properties of biofuels produced. The reaction was carried out in the reactor by varying the time (1, 2 and 3 hours), catalyst concentration (3, 5 and 7%), catalyst particle size (180, 250 and 630 μm) and reaction temperature (325, 350 and 375°C) . The optimum conditions for the catalytic cracking crude biodiesel process were obtained at: 3 hours, 7% catalyst concentration, catalyst particle size 180 μm and reaction temperature 375 ° C. The resulting biofuel contains 6.26% gasoline fraction (C5-C11); 17.6% kerosene (C12-C15), 47.73% biodiesel (C16-C20) and fatty acids 28.4%. Physical properties analysis showed density of 0.9631g/mL, pour point 12°C, flash point 49°C and octane number 72.6. Keywords: Catalytic cracking, crude biodiesel, octane number, biofuel.

Intrinsic Kinetics Study of Biogas Methanation Coupling with Water Gas Shift over Re-Promoted Ni Bifunctional Catalysts

The intrinsic kinetics of biogas methanation coupling with water gas shift over Re-promoted Ni bifunctional catalysts were investigated in this study. The catalysts were prepared through co-impregnation of Ni and Re precursors on the H2O2-modified manganese sand. The experiments were performed in a fixed bed reactor under the assorted reaction conditions of 300–400 °C, 0.1–0.3 MPa, and a 0.6–1.0 H2/CO ratio. The effect of gas internal and external diffusion on the performance of methanation coupling with water gas shift was examined by changing catalyst particle size and gas hourly space velocity (GHSV) and further verified by the Weisz–Prater and Mears criterion, respectively. It was found that the internal and external diffusions were eliminated when the catalyst particle size was 12–14 meshes and GHSV was 2000 h−1. Three kinetics models including the empirical model (EM), synergetic model (SM), and independent model (IM) were proposed, and 25 sets of experimental data were obtained to solve the model parameters. By mathematical fitting and analysis, it was discovered that the fitting situation of the three kinetics models was in the order of EM > SM > IM, among which EM had the highest fitting degree of 99.7% for CH4 and 99.9% for CO2 with the lowest average relative error of 8.9% for CH4 and 8.7% for CO2. The over 30% of average relative error for CO2 in IM might exclude the possibility of the Langmuir–Hinshelwood water gas shift mechanism in the real steps of biogas methanation coupling with water gas shift over Re-promoted Ni catalysts.

The Selectivity of Different Sized Catalysts on DOM Fractional Removal during the Catalytic Ozonation of Municipal Sewage

Dissolved organic matter (DOM) is a typical kind of pollutant with a complex composition, and different advanced treatments demonstrate different abilities toward its fractional removal. Hence, it is necessary to analyze the fraction of DOM that remains when using advanced treatments. In this paper, ozonation was used to deal with the biological effluents and comparisons of the catalytic ozonation with different particle sizes of γ-Al2O3 were made. The results of these comparisons indicated that the catalysts were active in improving the removal of DOM and γ-Al2O3 with different particle sizes can selectively remove DOM. The result of fluorescence showed that a decrease in the catalyst particle size contributes to a significant decrease in the fluorescence intensity, except for tryptophan-like substances. Meanwhile, DOM fractions with large molecular weights could be decomposed into small molecules by ozonation, resulting in increased hydrophilicity. However, the use of a catalyst in ozonation increased the removal of hydrophilic components. Additionally, a smaller catalyst particle size increased the removal of hydrophilic components. The results of catalyst analysis implied that the surface hydroxyl groups of catalyst γ-Al2O3 and the diffusion of DOM in the catalyst γ-Al2O3 played important roles in the ozonation catalytic process for the removal of DOM.