Boosting NiO Catalytic Activity by x wt % F‐ions and K₂O for the Production of Methyl Ethyl Ketone (MEK) via Catalytic Dehydrogenation of 2‐Butanol

Abstract

Herein, the synthesis of pure and modified mesoporous nanocrystalline NiO is reported. The catalyst was modified with different wt % F-ions or K 2 O and used to produce Methyl ethyl ketone (MEK) as a potential fuel/solvent. XRD analysis of the promoted catalysts confirmed the formation of Ni-metal covered by the host oxide, compared with pure NiO, especially for the promoted catalysts with x wt % F-ions. CO 2 -TPD results demonstrated the existence of different basic sites over these catalysts with varying strength. The catalytic conversion of sec-butanol (SB) into MEK over the parent NiO catalyst showed 52 % and 76.8 % conversion of SB at 250 and 275°C, respectively, with higher selectivity to MEK > 96 %. Among the promoted catalysts, NiO-10 wt % F À and NiO-1 wt % K 2 O catalysts showed 99 and 95 % conversion, respectively, with retaining the MEK selectivity of � 96 %. The catalytic activity, of the most active catalysts, was correlated with the presence of Ni/NiO interfaces, different types of basic sites, especially strong basic sites, and the surface area and porosity measurements.

Highly basic and active ZnO–x% K2O nanocomposite catalysts for the production of methyl ethyl ketone biofuel

“…This peak can be related to the formation of moderate basic sites over the surface of these samples as well as the desorption of bidentate and monodentate carbonates, respectively, formed during CO 2 adsorption over ZnO samples. 33 Increasing the amounts of K 2 O added to ZnO, that is, 5% and 10%, resulted in complete changes in their TG and DSC-TPD curves, as shown in Figure 4A,B. The % weight loss due to CO 2 desorption commenced early, around 50°C.…”

“…The % conversion of 2B and % selectivity of products were calculated as explained previously. 33 The schematic process of converting 2B into MEK is shown in Figure 1.…”

“…This phenomenon is associated with the early appearance of a new burly peak related to the desorption of bicarbonate species from weak basic sites, a decrease in the area of the moderate basic sites, and the appearance of strong basic sites at temperature ≥300°C, which is associated with desorption of bridged carbonate species. 33,53,54 The generation of different types of basic sites over ZnO-5% K 2 O and ZnO-10% K 2 O catalysts, with different strengths, could be related to progressively more frequent formation of Lewis basic sites (O 2− ) as explained by Equations ( 3)-( 5) 39 during the preparation of these mixtures at 400°C in an oxygen atmosphere. The total number of basic sites over all samples was calculated from TG-TPD curves as (no.…”

“…[27][28][29] It can be biotechnologically synthesized from biomass or 2,3butanediol, 30,31 by hydrogenation of 2,3-butanediol 32 and through dehydrogenation of 2-butanol (2B). 33,34 For all of these reasons, we have strongly encouraged the development of highly basic modified solid-catalyst, such as ZnO modified with 1%-10% K 2 O, and to examine these potent catalysts during the production of MEK at a relatively low temperature with higher selectivity. The innovation of this study can be summarized in a few points: (i) the simple preparation method of all catalysts at 400°C, (ii) the formation of a broad spectrum of different types of surface basic sites over these catalysts, and (iii) the optimization of the best experimental conditions for the direct production of MEK, at relatively low temperature with high selectivity, using fixed-bed reactor under atmospheric pressure.…”

Advanced Ordered Nanoporous Materials

“…The catalysts showed remarkable performance, except for Ni, in converting the lignite into arenes, phenols, alcohols, and esters with more than 97% yields. Halawy et al investigated the effect of F-ions and K 2 O addition onto mesoporous NiO catalyst to carry out the production of methyl ethyl ketone (MEK) (Halawy et al 2021). The mesoporous NiO catalyst showed a conversion of 77%, while the mesoporous NiO catalysts modified with F-ions and K 2 O showed conversions of 99 and 95%, respectively.…”