Sulfuric Acid Monitoring
Accurately monitoring sulfuric acid concentration in the alkylation process is essential for maintaining optimal reaction conditions and ensuring the efficiency of this critical refining operation. Traditional methods, such as laboratory titration, are reliable but can be time-consuming and require manual sampling, which interrupts continuous process control. A need exists for a reliable, in-situ method that can provide real-time monitoring without disrupting operations.
HORIBA’s Process Instruments has developed a fiber-coupled Raman scattering instrument tailored for this application. The Raman probe, constructed from durable carbon steel, is designed for direct insertion into the process stream without the need for sample conditioning. The system communicates with a base instrument remotely located in the safe environment of the control room, enabling seamless integration with refinery operations.
Your Simple, Cost-efficient Turnkey Solution
At HORIBA Process Instruments, we understand the unique demands of your industry. Our cutting-edge solutions are designed to deliver accurate, real-time insights for process optimization, safety, and compliance. From oil and gas to pharmaceuticals and beyond, we provide reliable tools that empower you to monitor critical parameters, reduce operational costs, and improve product quality.
Raman spectra of laboratory-prepared sulfuric acid dilutions
The HORIBA PI-200-L instrument has been used to record Raman spectra of laboratory-prepared sulfuric acid dilutions ranging from 95% to 85% acid concentrations. Changes in acid concentration are reflected in the Raman peaks: the peaks at 913 cm⁻¹ and 1162 cm⁻¹ decrease with dilution, while the peak at 1043 cm⁻¹ increases substantially. This combination of increasing and decreasing peaks creates a robust chemometric model for correlating Raman spectra with acid concentrations.
Typical online PLS analysis of the sulfur concentrations
Partial Least Squares (PLS) analysis was applied to 64 alkylation unit samples, using both the Raman spectra and laboratory titration data to build a predictive model. The PLS model leveraged the three prominent acid peaks in the 850 to 1250 cm⁻¹ wavenumber region and achieved a standard deviation of 0.11 %Wt for predicted versus laboratory values. This precision is well within the 0.2 %Wt variance inherent to conventional titration techniques.
The strong agreement between predicted and actual sulfuric acid concentrations demonstrates the reliability of on-line Raman spectroscopy for in-situ monitoring. By providing continuous, accurate, and non-invasive measurement, HORIBA’s Raman solution enhances process control, reduces sampling delays, and supports consistent alkylation unit performance. This advancement represents a significant step forward in optimizing refining operations through innovative monitoring technologies.
Resources
At HORIBA Process Instruments, we are committed to more than just delivering cutting-edge Raman technology—we aim to empower you with the knowledge and tools to excel in your industry. Our Resources & Knowledge Base is your go-to hub for expert insights, technical documentation, and best practices to optimize your process monitoring and analysis.
Learn Morecontact our experts
Send us a message or give us a call at (801) 322-1235 and our team will be in touch shortly.
*indicates a required field.