PTQ Q3 2025 Issue

Enhancing solvent system efficiency

Magnetic filtration technology has been developed to clean up challenging feed streams as well as circulating solvent systems

Sergio A. Robledo UNICAT Catalyst Technologies, LLC

I n the refining and petrochemical industries, the clean - liness and purity of circulating solvent streams is of paramount importance for stable operations, product quality, and efficiency. Contaminants, especially partic - ulate matter, can significantly degrade solvent quality, leading to excessive regeneration requirements, solvent degradation, and increased operational costs. For these challenges, the UNICAT MagAFS magnetic filtration tech - nology ensures cleaner solvent streams and more efficient operations. Solvent systems in downstream applications Solvent systems play a critical role in various refining and petrochemical processes. Amine systems, for instance, are essential for gas sweetening, removing hydrogen sulphide (H₂S) and carbon dioxide (CO₂) from natural gas and refin - ery gas streams. Extractive solvent systems for liquid-liquid extraction, such as those using sulfolane, are crucial for the recovery of aromatics like benzene, toluene, and xylene (BTX) from hydrocarbon mixtures. Electronic solvent sys - tems are vital in the manufacturing of high-purity electronic components and batteries, where even the smallest con - taminants can lead to significant defects. The efficiency and reliability of these solvent systems directly impact the overall performance and profitability of refining and petrochemical operations. Contaminants in these systems can lead to several operational challenges:  Excessive regeneration requirements : Particulates can foul solvent systems, necessitating frequent regeneration cycles, and/or increase the severity of regeneration pro - cesses. This not only increases operational downtime but also accelerates solvent degradation.  Solvent degradation : Frequent regeneration and the presence of contaminants can lead to the chemical breakdown of solvents, reducing their effectiveness and lifespan.  Increased costs : In addition to the operating costs associated with regeneration equipment, the need for fresh solvent make-up to replace degraded solvents adds to operational expenses. Additionally, poor-quality solvents can lead to further particulate generation, creating a vicious cycle of inefficiency.  Corrosivity and further particulate generation : Contaminated solvents can become corrosive, damaging equipment and generating more particulates, which further degrade solvent quality and system performance.

Negative aspects of poor-quality solvents Extractive separations, such as those used for BTX aromat - ics recovery, rely heavily on the quality of the solvent. Poor- quality solvents can lead to several detrimental effects:  Reduced separation efficiency : Contaminants in the sol - vent can interfere with the separation process, reducing the efficiency of extracting desired components like BTX.  Increased energy consumption : Contaminated solvents require more energy for regeneration and separation pro - cesses, leading to higher operational costs.  Equipment corrosion : Poor-quality solvents can become corrosive, damaging equipment and leading to increased maintenance and replacement costs.  Further particulate generation : Contaminated solvents can generate more particulates, exacerbating the problem and leading to a cycle of inefficiency and increased costs. Maintaining solvent purity in amine systems Amine systems are crucial for gas sweetening, which involves removing H₂S and CO₂ from natural gas and refinery gas streams. Maintaining solvent quality in amine systems is essential to prevent adverse conditions such as foaming and breakthrough of H₂S and CO₂ to downstream processing equipment. Some considerations include:  Foaming : Contaminants in amine solvents can cause foaming, which disrupts the absorption process and reduces the efficiency of gas sweetening. Foaming can lead to oper - ational issues such as increased pressure drop, reduced contact between gas and solvent, and potential carryover of amine into downstream equipment.1  Breakthrough of H₂S and CO₂ : Poor-quality amine sol - vents can lead to breakthrough of H₂S and CO₂, allowing these acidic gases to pass through the sweetening system and enter downstream processing equipment. This can cause corrosion, equipment damage, and create health, envi - ronmental, and safety hazards.2  Operational efficiency : Maintaining solvent purity ensures optimal absorption of acidic gases, reducing the need for fresh amine make-up and external amine regenera - tion cycles, minimising operational downtime.3 The MagAFS magnetic filtration technology addresses these issues by effectively removing particulates from sol - vent streams. Several of the key benefits include:  High efficiency in particulate removal : The filtration system can remove more than 95% of solid particles, including nanoparticles as small as 10 nm. This ensures

PTQ Q3 2025