Surface modification of spent coffee grounds using phosphoric acid for enhancement of methylene blue adsorption from aqueous solution.

In this study, the surface of the spent coffee grounds (SCG) was activated using phosphoric acid to increase the removal efficiency of methylene blue (MB) in aqueous solution, which is one of the harmful substances emitted in industrial processes. According to Fourier transform infra-red analysis, after phosphorylation of the SCG (PSCG), P = O group, P-O-C (aromatic) bond, P = OOH and P-O-P were newly introduced on the surface of the adsorbent, and the peaks of carboxyl groups and OH-group were large and broad. In addition, the surface area and mesopore range of the PSCG adsorbent were increased, and the structure changed, which enabled easy adsorption of MB. The process of adsorbing MB from aqueous solution using PSCG was more suitable for the pseudo-second order and Langmuir models, and the adsorption process was closer to chemisorption than physical adsorption. The maximum adsorption capacity of PSCG was 188.68 mg/g. As a result of the reuse test, PSCG showed excellent performance with a high removal efficiency of 90% up to four consecutive uses. PSCG modified with phosphoric acid, an abundant lignocellulose-based biosorbent that is readily available everywhere, is a promising adsorbent capable of adsorbing MB in aqueous solution.

How reliably can paediatric professionals identify pale stool from cholestatic newborns?

BACKGROUND: The success of surgery in infants with hepatobiliary disease is inversely proportional to the age when surgery was performed. Pale stool colour is a major indicator of biliary obstruction. However, simple recognition has been inadequate, resulting in late diagnosis and referral. Objective To assess the skills of healthcare professionals in recognising pale stools. METHOD: Photographs of normal, acholic and indeterminate infant stools were shown to paediatric professionals who have regular contact with jaundiced babies at three London teaching hospitals. Each stool was classified as 'healthy' or 'suspect'. RESULTS: One-third of the stools were not correctly identified by physicians and nurses. CONCLUSION: Experienced professionals often do not recognise stool colour associated with biliary obstruction. The authors propose that stool colour cards similar to those used in Japan and Taiwan may improve early detection of hepatobiliary disease at a minimal cost.