caa a22 4500 463219678 CHVBK 20180405153208.0 cr unu---uuuuu 170326e20071001xx s 000 0 eng 10.1134/S1061934807100164 doi (NATIONALLICENCE)springer-10.1134/S1061934807100164 Simultaneous determination of formaldehyde and methanol by flow-injection catalytic spectrophotometry [Elektronische Daten] [X. Yue, Z. Zhang] A flow-injection method is proposed for the simultaneous catalytic determination of formaldehyde and methanol on the basis of the catalytic action of formaldehyde upon the redox reaction between crystal violet and potassium bromate in a phosphoric acid medium and on-line oxidization of methanol into formaldehyde using a lead dioxide solid-phase reactor. The indicator reaction is monitored spectrophotometrically by measuring the decrease in the absorbance of crystal violet at the maximum absorption wavelength of 610 nm. A technique based on three sampling loops with a single injection valve is developed. The flow-injection system produces a signal of main peak with two shoulders of the same height. The height of the shoulders corresponds to the formaldehyde concentration, and the height difference between the shoulders and the main peak corresponds to the methanol concentration. The detection limit is 0.1 μg/mL for formaldehyde and 1.0 μg/mL for methanol with the sampling rate of 10 samples per hour. The relative standard deviations for 11 replicate determinations of formaldehyde (1.0 μg/mL) and methanol (10 μg/mL) are 1.1 and 2.1%, respectively. The method has been successfully applied to the simultaneous determination of formaldehyde and methanol in some gas samples. Pleiades Publishing, Ltd., 2007 Yue X. School of Chemistry and Materials Science, Shaanxi Normal University, 710062, Xi'an, China aut Zhang Z. School of Chemistry and Materials Science, Shaanxi Normal University, 710062, Xi'an, China aut Journal of Analytical Chemistry Nauka/Interperiodica 62/10(2007-10-01), 992-996 1061-9348 62:10<992 2007 62 10809 https://doi.org/10.1134/S1061934807100164 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1134/S1061934807100164 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Yue X. School of Chemistry and Materials Science, Shaanxi Normal University, 710062, Xi'an, China aut NATIONALLICENCE 700 1- Zhang Z. School of Chemistry and Materials Science, Shaanxi Normal University, 710062, Xi'an, China aut NATIONALLICENCE 773 0- Journal of Analytical Chemistry Nauka/Interperiodica 62/10(2007-10-01), 992-996 1061-9348 62:10<992 2007 62 10809 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer