Avaliação do tratamento térmico no catalisador magnético Ni0,5Zn0,5Fe2O4 e sua atividade catalítica na produção de biodiesel por transesterificação e esterificação simultânea do óleo de fritura

Abstract

Resumo O objetivo deste trabalho foi avaliar o efeito do tratamento térmico na síntese do catalisador Ni0,5Zn0,5Fe2O4 e o desempenho catalítico em reações de transesterificação e esterificação simultânea (TES) do óleo de fritura. Os catalisadores foram sintetizados por reação de combustão sem e com tratamento térmico sequencial a 800 °C com taxas de aquecimento de 30, 20 e 2 °C/ min. As caracterizações dos catalisadores indicaram presença majoritária da fase cristalina do espinélio inverso e de fases secundárias de ZnO e Fe2O3, porém a calcinação com taxas de 2 e 20 ºC/min promoveu a obtenção do espinélio monofásico. O catalisador polifásico foi mais efetivo do que o monofásico na produção de biodiesel, apresentando conversões de 84,1% e 76,8% em ésteres metílicos e etílicos, respectivamente, uma evidência da influência das fases secundárias na efetividade catalítica. Assim, o sistema polifásico de baixa cristalinidade obtido na combustão é promissor no processo catalítico de TES do óleo de fritura.

Solid Acid Resin Amberlyst 45 as a Catalyst for the Transesterification of Vegetable Oil

“…In these cases, Amberlyst 45 disperses well in the biphasic reaction mixture and mass transfer shall not limit the reaction, as previously observed for Amberlyst 15 (Boz et al, 2015). For acid-catalyzed transesterification, commonly, high alcohol loadings are needed (Boz et al, 2015;Alves et al, 2018;Cabrera-Munguia et al, 2018;Bernardes Costa et al, 2019;Kurhade et al, 2019;Silva et al, 2019;Syazwani et al, 2019;Wang et al, 2019;Andrade et al, 2020), and under this condition, Amberlyst 45 appears to be a more adequate catalyst for ethanolysis than methanolysis (Figure 4). This can represent great advantages in countries with a large production of bioethanol, such as the USA and Brazil, which happen to be also the largest producers of biodiesel (Biofuel.org.uk, 2010;Gallo et al, 2014).…”

Synthesis of NiMoO4 by the Complexation Method Combining EDTA-Citrate and its Behavior Against Biodiesel Acidity

“…If the molar ratio adopted in the present study (1:3) is compared with the other citations, it is much smaller than the majority of the reported cases 63,64,66,67 , with the exception of Perassi et al 65 that catalyzed ethyl transesterification with sulfuric acid, molar ratio (1:1) (Table 5). According to Oliveira et al 66 , the continuous generation of ethyl alcohol vapor during the transesterification reaction makes it necessary to use high oil:alcohol molar ratio much higher than the theoretical value 1:3, as shown in Equation 2.…”

“…In this universe, the emphasis in discussion is on the evaluation of the acidity index, a parameter focused on the quality of the synthesized biodiesel. According to Table 5, Pereira et al 63 and Silva et al 64 , also presented high acidity indexes (1.4 and 1.6 mgKOHg -1 ), in similar reaction conditions, but catalyzed with MCM-41 impregnated with zirconia and zinc doped nickel ferrite (Ni 0.5 Zn 0.5 Fe 2 O 4 ), respectively. Perassi et al 65 also have high indexes acidity (1.88-5.35 mgKOHg -1 ), even when catalyzed with sulfuric acid.…”

Synthesis of MoO 3 by pilot‐scale combustion reaction and evaluation in biodiesel production from residual oil

“…The addition of the residual oils and fats on biodiesel production is interesting from an economic and environmental viewpoint because it reduces the production cost and can mitigate the environmental impacts due to inadequate disposal 2,6 . The chemical reactions used to obtain biodiesel are transesterification and esterification, both of which can simultaneously occur (simultaneous transesterification and esterification (TES reaction)) if the raw material used (residual oil) contains FFA 1,2,4,6,7 . In transesterification, the triglyceride reacts with short‐chain alcohol in the presence of a catalyst, producing a mixture of FAAE and glycerol.…”