Hydroconversion of Vegetable Oils Isomerized over ZSM-5: Composition and Properties of Hydroraffinates

Abstract

Three vegetable oils (rapeseed oil, palm oil, and soybean oil) were isomerized (the so-called zeoforming process) using two different ZSM-5 catalysts (A or B) at a constant temperature (300 °C) and liquid hourly space velocity (LHSV) (1.0 h −1 ) and variable pressure (1.7, 2.5, or 4.0 MPa). The obtained isomerized zeoformates were hydrotreated under constant conditions (temperature, 340 °C; LHSV, 0.5 h −1 ; pressure, 4.5 MPa; and hydrogen/feed ratio, 1500 Nm 3 /m 3 ). The obtained hydroraffinates exhibited diverse contents of n-paraffins (24−83 wt %), isoparaffins (reaching greater than 50 wt %), aromatics (up to 15.1 wt %), and possibly compounds with alkyl naphthene structures. Hydroraffinates containing high aromatic contents also showed increased final boiling points (FBPs) of distillation, which was most likely related to the oligomerization reactions of fatty acids. The increase in pressure during the zeoforming process reduces the formation of aromatics and isoparaffins. Moreover, under the same temperature and pressure conditions, the zeoforming reactions of saturated fatty acids were more difficult, resulting in smaller yields of isoparaffins and aromatics in the hydroraffinates.

Diesel Fuel Containing Zeo-HVO Biocomponent Obtained from the ZEOFINING Process

“…The details of obtaining the biocomponent were consistent with the description given in the previous reports − and can be summarized as follows:…”

“…Hydroconversion relying on catalytic hydrogenation and deoxidation of triglycerides to n -paraffins is the basic process for the preparation of hydrocarbon fuel from vegetable oils, as widely described in the literature. − As a result of the poor low-temperature properties of n -paraffins obtained by direct hydroconversion of vegetable oils in many industrial processes, an additional processing stage of isomerization is used in the production of biofuels. − Isomerization of vegetable oil as the initial stage of hydroconversion is an alternative approach for biofuel production . This path was used in the ZEOFINING process.…”

“…The fundamentals of the ZEOFINING process are described in papers − and patents. − The essence of this process is the initial (prior to substantial hydroconversion) treatment of the raw material (vegetable oil) using a zeolite catalyst to modify fatty acid chains by isomerization.…”

“…1−3 Isomerization of vegetable oil as the initial stage of hydroconversion is an alternative approach for biofuel production. 16 This path was used in the ZEOFINING process.…”

Trace Elements in Vegetable Oils after Hydroconversion into Advanced-Generation Biocomponents

“…A two-stage hydroconversion process, including the initial zeoforming (isomerization) of vegetable oils, has been described in previous papers. − …”