Batch processes, nanofiltration

B. Catalyst Recycling using Nanofiltration in Batch Processes... 

Dendrimer-based organophosphites, organophosphonites, and organophosphi-nites, as well as their corresponding metal complexes, were described and patented by Tulchinsky and Miller for the hydroformylation of propene in batch processes [6], The recovery of the catalysts by means of nanofiltration was described for phosphite-substituted PAMAM dendrimers of generations G0-G4 (1). 

A batch of 80 L of feed volume (sample 1) containing 18 mg/L of fluoride and TDS of 820 ppm was introduced to a feed tank. Pressure on the feed side was adjusted to 15 bar and maintained constant during the run. The feed solution is processed through RO polyamide (PA) membrane and Functionalized Polyamide (HPA-250) Nanofiltration (NF) membrane. The reject or pass stream flow rate was maintained constant at 17 L/min. A recovery of 80% of volume in permeate with respect to the feed was attained and collected in a permeate tank. The flux of RO membrane was found to be 27 L/m whereas it was 46 L/m for NF membrane. The comparision of between RO and NF membranes are revealed in Table 4.4. Similarly, Sample 2 of fluoride concentration 1.05 mg/L and TDS of 610 ppm, tested at same operating conditions and summarized in Table 4.4. 

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