TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Process: In the process (2), the reaction is carried out at 60-200 degrees C. The process further comprises recovering the catalyst from the reaction mixture. The recovering step further comprises separating the catalyst from the reaction mixture, washing and drying the catalyst, and reusing the catalyst for producing alkyl esters. Preferred Components: The catalyst composition comprises: tricalcium silicate (25-75 wt.%), dicalcium silicate (10-40 wt.%), tricalcium aluminate (1-20 wt.%) and tetracalcium aluminoferrite (1-20 wt.%); or silicon dioxide (14-23 wt.%), aluminum oxide (3-6 wt.%), ferric oxide (2.5-6 wt.%), calcium oxide (43-67 wt.%), magnesium oxide (1-1.5 wt.%), sodium oxide (0-1.5 wt.%) and potassium oxide (0-5.4 wt.%). The catalyst composition further comprises at least one of magnesium oxide (0-1.5 wt.%), sodium oxide (0-1.5 wt.%), potassium oxide (0-5.4 wt.%) or hydrated calcium sulfate (0-10 wt.%). The catalyst composition comprises of cement. The cement is Portland cement, white cement, masonry cement, hydraulic and/or non-hydraulic cements. The nano composite catalyst comprises: tricalcium silicate (25-75 wt.%), dicalcium silicate (10-40 wt.%), tricalcium aluminate (1-20 wt.%) and tetracalcium aluminoferrite (1-20 wt.%). The catalyst of 1-30 wt.% is used in the process with respect to the feedstock.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The molar ratio of alcohol to feedstock is not greater than 30. The alcohol is methanol, ethanol, propen(en)ol and/or butan(en)ol. The fatty acid ester is a mono-, di- or tri-ester of glycerol with varied degree of unsaturation in the fatty acid chain. The nano composite catalyst (5 wt.%) is present in the catalyst composite and the remaining may be any inert or active component in the catalyst composite. The catalyst composition (5 wt.%) is present in the catalyst composite and the remaining may be any inert or active component in the catalyst composite. EXAMPLE - Soyabean oil (300 g), methanol (150 g) and catalyst (comprises catalyst composition comprising (in wt.%): silicon dioxide (14-23); aluminum oxide (3-6); ferric oxide (2.5-6); calcium oxide (43-67); magnesium oxide (1- 1.5); sodium oxide (0-1.5); and potassium oxide (0-5.4)) (30 g) were put into the batch reactor and maintained at 120-230 degrees C under autogenerated pressure for 6 hours. Then the reaction mass was allowed to reach room temperature. The product mixture was drained and catalyst was filtered. The two layers of liquid in the reaction mixture were separated. Then methanol was removed by distillation from both the layers separately and the solid catalyst was separated by filtration to give ethyl ester.