Online Quantitative Analysis of Chlorine Contents in Chlorinated Paraffins by Facile Raman Spectroscopy

Abstract

Online analysis of industrial chemicals is extremely important for managing product quality and performance. The chlorine (Cl) content is one of the most important technical metrics for chlorinated paraffins (CPs), and the conventional approaches to estimate Cl contents require transforming the Cl element to chloride followed by quantitative analysis with either titration or instrumentation, which are normally tedious and timeconsuming and cannot simultaneously guide the industrial production. Here, we developed a rapid, real-time, and online approach to determine the Cl content of CPs with facile Raman spectroscopy. The chlorination of paraffins generated two new Raman peaks at 610−618 and 668−690 cm −1 , which are associated with the vibrational modes of the S HH and S HC conformations of the C−Cl bond in CPs, respectively. More importantly, the corresponding peak of the S HH conformation decreased and that of the S HC conformation increased with the enhancement of the chlorination degree of CPs. The ratiometric calculation of the two respective Raman peak areas leads to a quantitative analysis of the Cl content of CPs. The developed approach can online provide the Cl contents of CPs within seconds accurately but without the tedious sample treatment required by conventional approaches. The strategy of integrating Raman analysis with the industrial pipeline will help in managing the production and quality control of industrial chemicals.

Hydrophobization of Reduced Graphene Oxide Aerogel Using Soy Wax to Improve Sorption Properties

“…In addition to peaks D and G, other narrower peaks can be seen in spectrum 2, displayed in red color. The positions of some peaks are the same as peak positions in the paraffin spectra; in particular, the position of the peak at 1128 cm −1 coincides with the position of the ν as (CC) peak of paraffin [ 34 , 35 , 36 , 37 ]. It can be thought that this point of the analysis zone contains mostly soy wax.…”