Production of renewable hydrocarbons from vegetable oil refining by-product/waste soapstock over selective sulfur-free high metal loading SiO2-Al2O3 supported Ni catalyst via hydrotreatment

The performance, selectivity, recovery, and reusability of high metal loading commercial Ni66 +/- 5%/SiO2-Al2O3 catalyst were studied in renewable hydrocarbon synthesis from low cost raw material pretreated soapstock (TS) by solvent-free one-pot hydrotreatment (HT). TS was extracted from rapeseed oil chemical refining by-product/waste soapstock (SS) by developed simple treatment method. The catalyst was characterized by FE-SEM, TEM, XRF, XRD, and N-2 sorption analysis. Feedstock, liquid, and gaseous products were analyzed by FT-IR, GC-FID, GC-MS, GC-TCD, and CHNS elemental analysis. The effect of initial H-2 pressure (2-8 MPa), catalyst amount (3-9%), reaction temperature (280-340 degrees C), and residence time (15-60 min) on hydrocarbon production were investigated. Combustible gases and pure marketable linear saturated hydrocarbons with high yield 79.1%, calorific value 47.22 MJ/kg, C/H ratio 5.6, and n-C17 content 82.7% were successfully produced from TS using minimum effective catalyst amount and reaction conditions: 5%, 6 MPa, 320 degrees C, and 30 min. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The study investigated the performance, selectivity, recovery, and reusability of a commercial Ni66 +/- 5%/SiO2-Al2O3 catalyst in renewable hydrocarbon synthesis. By using a solvent-free one-pot hydrotreatment method, combustible gases and high yield linear saturated hydrocarbons were successfully produced from low cost raw material pretreated soapstock, indicating the potential for green energy production.