Conversion of Crude Glycerol from by-Product Biodiesel into Bio-additive of Fuel through Acetylation Reaction based on Modified Zeolite Catalyst

Abstract

<jats:p>&lt;p class="BodyAbstract"&gt;Biodiesel is one of the alternative fuels produced from the transesterification reaction between triglycerides and alcohols with glycerol by-products. So far, the resulting crude glycerol has not been maximally utilized because of its low purity. So, it is necessary to purify glycerol before turning it into a more useful compound. The purified glycerol can be reacted with acetic acid within esterification reaction (acetylation process) using an acid catalyst to produce glycerol triacetate (triacetin). One of the uses of triacetin as an additive in gasoline and biodiesel. The purpose of this study is to utilize glycerol from by-products from biodiesel production to bio-additive materials that can improve fuel quality and are environmentally friendly. The method used in this study begins with the purification of crude glycerol, modification of zeolite catalyst with impregnated of nickel metal followed by an acetylation reaction which held on temperature of 100°C for 60 min. The experimental results are analyzed using base titration to determine the remaining unreacted acids and are applied as bio-additives by adding them to commercial fuels and measured the increasing octane numbers. The result shows that the reaction conversion increases with increasing mole ratio of reactants and catalysts with the best results in the mole ratio of acetic acid and glycerol is 9:1 and catalyst 5% by weight of acetic acid with a conversion of 66.02%. As bio-additives the reaction product could increase the octane number of commercial fuel by 6.5 up to 8.5%.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;Keywords: glycerol, acetylation reaction, mofified zeolite, bio-additive</jats:p>

Optimization and Characterization of Mesoporous Sulfonated Carbon Catalyst and Its Application in Modeling and Optimization of Acetin Production

“…This is expected since glycerol acetylation is an endothermic reaction. Therefore, the reaction rate usually increases with temperature and enhances the diffusion of reactants and products in and out of active sites [ 14 , 55 , 56 ]. In contrast, a concurrent increase in G/AA mole ratio and temperature results in a decrease in both MA and DA, respectively ( Figure 11 b,c).…”

“…However, triacetin is considered the most valuable, yet its selectivity is limited despite the use of several types of heterogeneous catalysts such as a sulfonic acid resin (amberlyst-15, amberlyst-35, and amberlyst-36), heteropoly acid, zeolites, etc. [ 12 , 13 , 14 ]. The low selectivity has been attributed to the weakening acid strength of the catalysts, restricted access to the acidic sites, high molecular weight and active site ratios, narrow pores, presence of water, sequential acetylation of the hydroxyl groups, and low surface areas in some.…”

Simulasi Stoichiometric Reactor Pada Produksi Triasetin Berbasis Chemcad

“…Tingginya produksi biodiesel di Indonesia sebanding dengan jumlah produk samping gliserol yang dihasilkan, sehingga gliserol dapat dimanfaatkan salah satunya untuk memproduksi bahan aditif kendaraan yairu triasetin. Bahan aditif dibutuhkan untuk meningkatkan angka oktan dan meningkatkan efisiensi pembakaran pada mesin [3]. Triasetin adalah bahan aditif 98 yang ditambahkan ke dalam bahan bakar kendaraan untuk menyempurnakan pembakaran dalam ruang bakar mesin sehingga mengurangi knocking pada mesin kendaraan bermotor dan merupakan bahan aditif ramah lingkungan [4].…”

“…Triasetin adalah bahan aditif 98 yang ditambahkan ke dalam bahan bakar kendaraan untuk menyempurnakan pembakaran dalam ruang bakar mesin sehingga mengurangi knocking pada mesin kendaraan bermotor dan merupakan bahan aditif ramah lingkungan [4]. Triasetin merupakan bahan aditif yang ramah lingkungan dibandingkan dengan Tetraethyl Lead (TEL) yang yang bersifat toksik timbal dan Methyl Tertiary Butyl Ether (MTBE) yang memiliki sifat karsinogenik dalam air, sehingga jika tumpah ditanah akan mencemari sumber air disekitarnya [3]. Triasetin diproduksi dari reaksi esterifikasi gliserol dan asam asetat menggunakan katalis homogen maupun heterogen yang bersifat asam.…”

Characterization and Preparation of Ni/γAl2O3 Catalyst for Acetylation of Glycerol in a Fixed Bed Reactor Applied as an Octane Booster for Commercial Fuels

“…From previous studies it was explained that heterogeneous catalysts resulted in higher glycerol conversion and selectivity to the desired product. On the other hand, solid acid catalysts such as zeolite, amberlyst and heteropoly acid show good thermal stability and regeneration ability as well as specific surface area convinient for esterification reactions (Dewajani et al, 2019;Mufrodi et al, 2013;Okoye and Hameed 2016). In this study, the acid-solid catalyst properties were improved by modifying the catalyst using metal oxides so as to produce a catalyst that is more stable, easy to regenerate and has more active sites.…”