Heavy aromatics transalkylation (TransPlus℠ 5)  

The TransPlus℠ 5 process is a low-cost, high-conversion technology to upgrade C₉₊ aromatics and toluene to higher-value mixed xylenes and high purity benzene products. Benzene can also be co-processed for additional mixed xylenes production. The TransPlus 5 process, which is based on a proprietary high-activity, co-extruded dual zeolite catalyst with low precious metal content, offers superior yields, longer cycles, lower operating costs and increased profitability. The TransPlus 5 process can also be licensed by Axens as part of the ParamaX® technology suite for grassroots aromatics complexes.

The following simplified flowscheme shows the TransPlus 5 process in a typical fractionation and recovery section of an aromatics complex.

The TransPlus 5 process delivers improved products yields, very low ring loss, improved benzene purity and significantly extended cycles. While cycles of 7+ years have been achieved with the first generation catalysts, significantly longer cycles are anticipated with the TransPlus 5 process, now in commercial operation. Multiple in-situ regenerations of previous generation catalysts have been commercially demonstrated. Likewise, the catalyst used in the TransPlus 5 process is fully regenerable in-situ, allowing continued operation for many years beyond the first cycle. The TransPlus 5 process delivers substantial improvements over its predecessors such as higher C₉₊ aromatics conversion per pass, higher selectivity to xylenes and benzene products, lower aromatics ring loss, longer cycles and reduced installed costs. The TransPlus 5 process operation at higher C₉₊ aromatics conversion per pass allows reduced recycle rates and reduced operating costs versus prior generations.

The TransPlus 5 process is the third generation of transalkylation technology licensed by ExxonMobil. The process features a high-activity, co-extruded dual zeolite catalyst formulation with low precious metal content, higher operating weight hourly space velocity (WHSV), and an expanded temperature window compared to the prior generation technology.

The TransPlus 5 process is capable of handling fresh feeds with compositions from very light feeds up to and including 100% C₉₊ aromatics. In addition, the TransPlus 5 process can process C₉₊ heavy aromatics with either toluene, benzene or any combination of the two as co-feeds. This broad feedstock flexibility provides licensees with exceptional operating flexibility and profit-maximizing potential. For example, licensees have increased flexibility to optimize the disposition of the C₉₊ aromatics stream by enabling incremental production of mixed xylenes and reducing the heavy aromatics content in gasoline in order to meet reformulated fuel requirements or distillation specifications. Licensees can also upgrade benzene product to mixed xylenes when it is economically attractive.

• Initial discussions to confirm client objectives and tailor the solution
• Detailed yield estimate
• Feasibility study
• Commercial proposal
• Process design package
• Technology transfer, training, catalyst loading and startup support
• Technology improvement
• Performance monitoring and technical assistance throughout the life of the catalyst