title: A continuous process for biodiesel production in a fixed bed reactor packed with cation-exchange resin as heterogeneous catalyst.
abstract: Continuous esterification of free fatty acids (FFA) from acidified oil with methanol was carried out with NKC-9 cation-exchange resin in a fixed bed reactor with an internal diameter of 25 mm and a height of 450 mm to produce biodiesel. The results showed that the FFA conversion increased with increases in methanol/oil mass ratio, reaction temperature and catalyst bed height, whereas decreased with increases in initial water content in feedstock and feed flow rate. The FFA conversion kept over 98.0% during 500 h of continuous esterification processes under 2.8:1 methanol to oleic acid mass ratio, 44.0 cm catalyst bed height, 0.62 ml/min feed flow rate and 65°C reaction temperature, showing a much high conversion and operational stability. Furthermore, the loss of sulfonic acid groups from NKC-9 resin into the production was not found during continuous esterification. In sum, NKC-9 resin shows the potential commercial applications to esterification of FFA.
authors.affiliation: The State Key Lab of Hollow Fiber Membrane Materials and Processes, School of Material and Chemical Engineering, Tianjin Polytechnic University, Tianjin, PR China.
authors.forename: Yaohui
authors.initials: Y
authors.lastname: Feng
authors.forename: Aiqing
authors.initials: A
authors.lastname: Zhang
authors.forename: Jianxin
authors.initials: J
authors.lastname: Li
authors.forename: Benqiao
authors.initials: B
authors.lastname: He
mesh_terms: D000818:Animals; D056804:Biofuels / Q000032:analysis*; D019149:Bioreactors; D002384:Catalysis; D002411:Cation Exchange Resins / Q000737:chemistry*; D005399:Fishes; D012037:Refuse Disposal / Q000379:methods*; D012867:Skin / Q000737:chemistry*; D013024:Soybean Oil / Q000737:chemistry*
chemical_list: D056804:Biofuels; D002411:Cation Exchange Resins; D013024:Soybean Oil