Catalysis 2025 Issue

hazardous classification. Any losses or liabilities incurred will ultimately affect the company’s bottom line, not the contractor’s. Managing the shipment of hundreds of metric tons of spent catalysts, which contain significant values in plati - num, palladium, and other PM, is best handled by special - ists. Sabin International Logistics Corporation (SILC) has previously discussed the intricate web of domestic and international regulations, permits, and logistical hurdles involved in shipping PM-bearing catalysts, elaborating on the process of organising transportation from any global location to Sabin’s recovery and refining facilities. The reliability of the chosen PM refiner is crucial for receiv - ing quality service. Ethical compliance in the PM industry is essential to avoid financial and legal risks. Catalyst owners should be diligent in selecting a PM recycler, as unethical practices, such as misrepresenting metal content or other deceptive behaviours, have been prevalent in the industry. Consulting regulatory bodies and media sources are rec - ommended to ensure a comprehensive investigation and verification of the recycler’s financial standing, safety, envi - ronmental compliance, and other certifications. The vendors in the world of PM refining can be classified as brokers, secondary refiners, and primary refiners: Brokers : Not an actual PM refiner, but a middleman who must, in turn, have the PM recovered by a secondary or primary refiner, which will be discussed in further detail. If the catalyst owner finds themselves in need of fast cash for their PM content, a reputable broker may be a good option. The trade-off will be sacrificing a large percentage of the overall market value of the PM, sometimes as high as 50%. Secondary refiners : These companies essentially serve the low-volume market, as they typically run small-capacity processing and sampling operations. The purpose of the secondary refining side is to collect various materials and combine them into larger parcels, possibly upgrading them somewhat along the way. They do not produce pure PM and must ship their ultimate output to a primary refiner, so they are also a form of middleman. Primary refiners : Companies that produce 99.9%+ pure PMs for return to the market (fully accredited and accepted by the banks, jewellery makers, and catalyst manufactur - ers). All the legitimate, certified, fine PMs on Earth come through a primary refiner. The need to protect human rights and the environment requires strict adherence to all aspects of responsible sourcing and risk awareness. This protects customers, PM refiners, and ultimately all their employees and the end consumer. The Good Delivery programme from the London Platinum and Palladium Market (LPPM) and the Responsible Sourcing programme from the London Bullion Metals Association (LBMA) provide owners of PM assets with lists of acceptable PM refiners. These certifications are critical to risk management. There has been increasing scrutiny of the PM industry from the US Department of Treasury, the LPPM, and the LBMA over the last 10 or more years. Concerns about drug car - tels, terrorist groups, and other criminals make it mandatory for refiners to actively participate in stringent due diligence

and anti-money laundering (AML) programmes. The Good Delivery and Responsible Sourcing designations, therefore, not only accredit the technical aspect (the ability to refine gold, silver, platinum, and palladium to 99.9%+ levels), but also include passing the strict sourcing audits annually. It is expected that compliance requirements will continue to grow more complex in the future as efforts expand to fur - ther guarantee responsible sourcing. Traditionally, recovery of platinum group metals and rhe - nium from petroleum and petrochemical catalyst is accom - plished by dissolving the spent catalysts in strong caustics or acids. This hydrometallurgical recovery process is com - monly referred to in the industry as ‘digesting’. Except for aluminosilicates (or zeolites), digestion serves well in recovering the PM from spent process catalysts in most cases. Certain events and circumstances encountered over the life of the catalyst, however, can create many problems when trying to digest: • Overheating during operation can harden substrates (gamma alumina converting to theta or alpha alumina), rendering them insoluble to even powerful solvents. • Excessive fines or carbon content can prevent exposure of the catalyst surface area to the solvents. • Metals present in the feed, or additives introduced to extend catalyst life, can create chemical imbalances and interfere with the desired chemical reaction. Individually, each of these factors can reduce PM recov - ery, and in combination these effects can be great. In some cases, for example, as much as 20 or 30% of the rhenium contained can remain insoluble. Should these insoluble materials still hold PM, the hydrometallurgical refiners must send them out to a copper smelter to recover the platinum group metals, but the rhenium (Re) is lost. A refiner that uses pyro-metallurgical technology such as Sabin’s proprietary Pyro-Re process (see Figure 1 ) can Figure 1 Pyro-metallurgical processes are required to recover and refine every possible ounce of precious metals like rhenium (Re) from catalytic operations in refinery and petrochemical facilities

Catalysis 2025