Applications with keyword: Simple cleanup
Photos showing how grinding caused by stirring of molecular sieves can be completely avoided by using a rotating bed reactor (RBR). Molecular sieves contained in a RBR for a 200 mL vessel can theoretically hold 0.23 moles of water. This allows synthesis of product in the range of 100 gram by ester condensation or drying of 25 litres of analytical grade organic solvent.
Conditions: Molecular sieve (3 Å, rods 3-5 mm, 15 g), placed either into a SpinChem® S221 rotating bed reactor (RBR) or free in solution agitated by a 3-blade stainless steel propeller (5 cm), both operated at 500 rpm within a SpinChem® V211 flower-baffled reaction vessel containing isopropanol (130 mL). Photos were taken after 24 hours of operation with the RBR and stirrer in place, respectively. The theoretical calculation assumed an RBR with space for 20 g molecular sieve with a 20% (w/w) water adsorption capacity, a synthesis yield of 99%, a product weight of 450 g/mol, and an organic solvent with a density of 0.8 kg/L and an initial moisture content of 200 ppm; data partly taken from literature; J. Org. Chem. 2010 (75) 8351-8354.
Accelerated video showing the enhanced adsorption rates of methylene blue onto activated carbon using a rotating bed reactor (RBR) compared to a stirred tank reactor (STR). The RBR decolourized the solution almost twice as fast, did not create any visible fines and required no filtration.
Conditions: Adsorption of methylene blue (100 mg) onto activated carbon (40 mL, 12-40 mesh) placed either in a SpinChem® S311 rotating bed reactor (RBR) or stirred free in solution agitated by a 5 cm impeller, both operated at 800 rpm within a SpinChem® V311 flower-baffled reaction vessel containing 1000 mL water at room temperature. The video is shown at 12x the normal speed. The solution was decolourized after 5 minutes with the RBR, versus close to 10 minutes with the stirred tank reactor (STR). Samples from the RBR set-up required no filtration, but from the STR all samples required filtration through a 45 µm syringe filter for analysis.
Learn how SpinChem rotating bed reactors (RBR) can eliminate poor mass transfer in heterogeneous reactions during chemical synthesis and biotransformations. Preserve activity and facilitate recycling of solid phases with the RBR. This brochure shows technology and applications.