Online analytical instruments for sulfonation analysis

This post was last edited by qugd on 2018-2-5 at 15:40. In the process of alkylbenzene sulfonation, fuming sulfuric acid or concentrated sulfuric acid is generally used as the sulfonating agent. Due to the strong acidic environment in this reaction, the detectors or probes of many online analyzers cannot withstand the conditions present during the reaction. Therefore, for the several monitoring parameters you mentioned, aside from color, it is difficult to develop online analyzers since sample processing and the use of chemical reagents are required. Moreover, given the limited market demand for analyzers specifically designed for this alkylbenzene sulfonation process, it may not be economically viable for analyzer manufacturers to create such online analyzers; hence, no such devices exist. You can inquire with some more professional manufacturers of online analyzers, stating your specific requirements and sample conditions, and ask them to design an online analysis system suitable for your application conditions; however, the price might be beyond your budget. Any type of online analyzer, no matter how simple it may be, will have a very high price if there is low demand in the market. The market acts as an invisible force, and its ability to influence prices is far greater than one might imagine.

When determining the median value, it is probably the saponification value; hydrolysis is required to separate the alkyl sulfonic acids, followed by acid-base titration in a non-aqueous solvent. Conducting this test in a laboratory is also quite troublesome. Inorganic acids (acid value), namely the sulfuric acid remaining from the reaction process; at this point it is necessary to find ways to eliminate the effect of the resulting sulfonates or sulfonamides, which may also involve separation. This sample processing is quite complicated, after which the separated acid is neutralized and titrated. Free oil, that is, unreacted alkylbenzenes or other hydrocarbons, must be separated from these residual oils in a system with high surface activity; this may require the use of special extraction methods or other particular separation techniques, in order to quantitatively determine the amount of oil that has been separated. This is also a very difficult sample analysis process. You can inquire about online near-infrared analysis systems; there might be solutions available. However, the complexity of such analysis systems – including sampling, sample preparation, establishing the spectral model of the analyzer, and subsequent training and maintenance of the model – may be beyond what you or your organization can handle. Additionally, the conditions of the sample system may impose certain limitations on this analysis method.

Thank you to the person above. It should be noted that in current sulfonation techniques, SO3 is directly used in contact with alkylbenzenes, without the use of fuming sulfuric acid or concentrated sulfuric acid.

1. On the contrary, as for color, there are mature online industrial colorimeters available; if you need more information, please leave your contact details. 2. For the testing of the neutralization value of inorganic acids, samples are required, and the titration is carried out in the laboratory using an automatic titrator. Please note that even online titration is not real-time. Since direct sulfonation of SO3 yields a multi-component anhydrous mixture, it is difficult to determine it directly using methods such as conductivity and refractive index. 3. The measurement of free oil, in my opinion, should be possible to carry out online using optical methods such as infrared and ultraviolet spectroscopy. The principle is similar to that of an oil analyzer in water, but this still requires further demonstration. 4. The near-infrared online systems recommended by QUGD friends seem to be available from several brands in Japan, such as KURABO; they can be used to analyze mixtures, but indeed a large amount of data is required as a basis for this.