Isolation and characterisation of L-quebrachitol from rubber factory wastewater

In the production process of natural rubber (nr),large quantities of wastewater containing substantial amounts of l-quebrachitol are discharged. to date,published methods of extracting l-quebrachitol from wastewater are still at the laboratory stage. in this study,membrane separation technology was applied to the extraction of l-quebrachitol from wastewater and the experimental parameters were studied in order to determine optimal experimental conditions. results show that the optimum source material for l-quebrachitol extraction was the serum collected by squeezing the latex coagulum. when this serum was passed through a microfiltration (mf) membrane and two ultrafiltration (uf) membranes,majority of the organic impurities were removed. the resulting ultrafiltrate was concentrated by a nanofiltration (nf) membrane and washed twice. finally,a new and convenient approach for large scale extraction of l-quebrachitol is proposed combining membrane separation and crystallisation. the output achieved with this approach would be 10 kg per year under laboratory conditions with 99.20% purity. the structure of l-quebrachitol was confirmed by elementary analysis,infrared (ir) spectroscopy,nuclear magnetic resonance (nmr) spectroscopy,mass spectroscopy (ms) and single-crystal x-ray diffraction.