KY-403 Petroleum Products Acid Number Analyzer by Keyuan Instruments

Overview

The KY-403 Petroleum Products Acid Number Analyzer is an automated potentiometric titration system engineered for precise determination of acid number (AN) in crude oils, refined petroleum products, and lubricants. It operates on the fundamental principle of potentiometric endpoint detection—measuring the potential shift across a high-impedance pH-sensitive electrode pair during titration with standardized alcoholic potassium hydroxide (KOH) solution in a toluene–isopropanol solvent matrix. This method conforms rigorously to internationally recognized standard test procedures, including ASTM D664 (equivalent in scope to GB/T 7304–2000) and ASTM D974 (aligned with GB/T 18609), ensuring traceable, auditable, and inter-laboratory comparable results. Designed for routine QC/QA workflows in refinery laboratories, third-party testing facilities, and R&D centers, the KY-403 delivers reproducible acid number quantification down to 0.001 mg KOH/g—critical for monitoring oxidation stability, corrosion risk, and additive depletion in hydrocarbon streams.

Key Features

• Automated potentiometric titration platform with integrated microprocessor control and real-time voltage acquisition at 10 mV resolution
• Imported anti-diffusion titration head minimizing reagent carryover and ensuring consistent drop formation
• Self-calibrating burette drive mechanism with 10 mL glass syringe-type burette, certified accuracy of ±0.1% full scale
• Dynamic endpoint recognition algorithm applying Savitzky–Golay smoothing to raw titration curves, followed by first-derivative inflection point refinement
• Full Windows-based graphical user interface supporting step-by-step guided operation, method recall, and parameter locking per SOP
• Automatic sequence execution: solvent blank correction, electrode conditioning, sample dissolution, titrant delivery, endpoint validation, and post-titration rinse cycles
• Built-in thermal drift compensation for electrode potential stabilization over extended run times (up to 8 h continuous operation)

Sample Compatibility & Compliance

The KY-403 accommodates a broad spectrum of liquid hydrocarbon matrices—including naphthas, diesel fuels, base oils, transformer oils, and crude fractions—provided they dissolve homogeneously in the specified toluene–isopropanol (1:1 v/v) titration medium. It is validated for use under ISO/IEC 17025-accredited testing environments and supports full compliance with regulatory frameworks governing petroleum product quality: GB/T 7304–2000, GB/T 18609–2010, ASTM D664–22, and ASTM D974–21. All measurement data—including raw mV vs. volume traces, calculated equivalence points, and operator annotations—are time-stamped and stored with immutable audit trails, satisfying GLP documentation requirements and enabling 21 CFR Part 11–compliant electronic record retention when deployed with validated LIMS integration.

Software & Data Management

The embedded Windows 10 IoT Enterprise software provides dual-mode operation: standalone local control or networked deployment via Ethernet TCP/IP. Method templates are configurable per product grade (e.g., “Crude AN – High Range”, “Lube Oil AN – Low Range”) and include adjustable parameters such as stirring speed (150–300 rpm), titrant concentration (0.01–0.1 mol/L KOH), and endpoint sensitivity thresholds. Data export options include CSV, PDF analytical reports (with lab header, analyst ID, instrument serial number, and calibration certificate references), and direct ODBC connectivity to enterprise laboratory information management systems (LIMS). All critical events—including power interruption recovery, electrode offset drift alerts, and burette air bubble detection—are logged with ISO 8601 timestamps and retained for ≥12 months.

Applications

• Monitoring acid number increase during thermal aging of turbine and hydraulic oils per ASTM D2440
• Quantifying naphthenic acid content in heavy crudes prior to desalting and distillation
• Verifying acid number specifications for jet fuel (ASTM D3242) and marine residual fuels (ISO 8217)
• Supporting catalyst deactivation studies in hydrotreating units through feedstock acidity profiling
• Conducting comparative oxidation stability assessments per RP-227 (API RP 227) using accelerated aging protocols
• Validating neutralization efficiency of alkaline additives in engine oils and gear lubricants

FAQ

What solvent system is required for accurate acid number determination on the KY-403?
Toluene and isopropanol in a 1:1 (v/v) mixture is mandatory; alternative solvents invalidate conformance with GB/T 7304 and ASTM D664.
Does the instrument support multi-sample batch processing without manual intervention?
Yes—when equipped with an optional 12-position autosampler, the KY-403 executes unattended sequences including electrode cleaning, blank subtraction, and result validation per IEC 61000-4-30 immunity standards.
How is electrode calibration verified during daily operation?
The system performs automatic open-circuit potential (OCP) checks before each analysis and logs deviations exceeding ±15 mV from baseline; users may initiate two-point buffer calibration (pH 4.01 and 7.00) at any time.
Can measurement uncertainty be estimated directly within the software?
Yes—the software calculates expanded uncertainty (k=2) based on burette volumetric error, titrant molarity uncertainty, electrode repeatability (per NIST SP 800-142), and sample mass variability, outputting a GUM-compliant uncertainty budget with each report.
Is firmware upgrade capability available remotely?
Firmware updates are delivered via encrypted USB key only; no remote internet connection is permitted to maintain data integrity and cybersecurity compliance per ISO/IEC 27001 Annex A.8.2.3.