Novel Heterogeneous SO₃Na-Carbon Transesterification Catalyst for the Production of Biodiesel

Abstract

Glycerol, a major biodiesel by‐product, was valorised into a novel and highly stable heterogeneous carbon‐based solid base catalyst with transesterification activity. The SO3H‐carbon catalyst developed previously by us from glycerol was modified into base catalyst by treating with aqueous alkali under controlled conditions. The reported solid base catalyst is first of its kind having polycyclic aromatic carbon sheets attached with ‐SO3Na, ‐COONa and ‐ONa functionalities. The catalyst was characterized for its structural properties using XRD, FTIR, 13C‐MAS NMR, XPS, EDAX, SEM, TEM, TG/DTA, ICP‐OES and Raman spectral techniques. The SO3Na‐ catalyst was employed for the transesterification of sunflower oil to fatty acid methyl esters (biodiesel) in high yields (99%) at atmospheric pressure. The strong basic sites of the catalyst contributed to its remarkable performance and the activity was intact even after 8 cycles of reuse without any leaching, indicating its high structural stability. Thus, the reported SO3Na‐carbon catalyst possessed the potential of green and economic biodiesel production from oils & fats apart from clean glycerol as by‐product.

Highly Active MgP Catalyst for Biodiesel Production and Polyethylene Terephthalate Depolymerization

“…For the biodiesel production some heterogeneous catalysts have been tested, [7–9] and the alkaline metal oxides like BaO, CaO, MgO, and SrO have proven to be efficient due to their basicity, low activation temperature, and shorter reaction times [10,11] . From these groups of metal oxides, magnesium oxide has attracted the attention of the scientific community, due to its considerable basicity, stability, and not dissolution in the reaction medium [12,13] …”

Carbon‐SO3Na Catalysed Synthesis of Glycerol Carbonate via Transesterification of Glycerol and Dimethyl Carbonate

“…Based on structural characterization, the carbon‐SO 3 Na catalyst was found to be non‐porous by its low BET surface area of 6.5 m 2 /g with sodium content of 6.73 %. The carbon‐SO 3 Na catalyst had a relatively high total basicity of 6.58 mmol/g corresponding to −SO 3 Na, −COONa &−ONa functionalities and exhibited excellent transesterification activity for the methanolysis of vegetable oils to biodiesel making the biodiesel process more clean and green [46] . In continuation to explore its possible applications in organic transformations, in the present study, the carbon‐SO 3 Na catalyst was employed for the synthesis of glycerol carbonate (GC) from glycerol and DMC via transesterification process (Scheme 1).…”

“…These catalysts demonstrated their effectiveness towards the esterification of fatty acids to biodiesel as well as for different organic reactions [45] . Latter, the carbon‐SO 3 H catalyst was modified to its sodium salt as a solid base catalyst (carbon‐SO 3 Na) by treating with aqueous sodium hydroxide under controlled conditions [46] . Based on structural characterization, the carbon‐SO 3 Na catalyst was found to be non‐porous by its low BET surface area of 6.5 m 2 /g with sodium content of 6.73 %.…”

“…[45] Latter, the carbon-SO 3 H catalyst was modified to its sodium salt as a solid base catalyst (carbon-SO 3 Na) by treating with aqueous sodium hydroxide under controlled conditions. [46] Based on structural characterization, the carbon-SO 3 Na catalyst was found to be non-porous by its low BET surface area of 6.5 m 2 /g with sodium content of 6.73 %. The carbon-SO 3 Na catalyst had a relatively high total basicity of 6.58 mmol/g corresponding to À SO 3 Na, À COONa &À ONa functionalities and exhibited excellent transesterification activity for the methanolysis of vegetable oils to biodiesel making the biodiesel process more clean and green.…”