Liquid-crystal-display glass may contain a thin indium tin oxide coating that can be targeted by hydrometallurgical recycling. Hydrochloric acid has been evaluated for transferring indium into solution before selective separation, but whole devices also contain polarizers, adhesives, metals, backlights and other materials. Dismantling quality and glass preparation can influence results as much as acid concentration. Buyers need a reagent specification linked to indium yield, tin and other impurities, solvent extraction, chloride recycle and residue quality. This guide covers industrial qualification rather than operational conditions.

For industrial qualification, assign purchasing, quality, engineering, operations, logistics and EHS ownership before the first commercial delivery. Approve hydrochloric acid concentration, analytical methods, sampling, storage conditions, transfer equipment, deviation response and release authority in writing. Compare representative lots under controlled conditions and record acid consumption, process performance, corrosion observations, mass balance, waste and final product quality. This separates raw-material variation from changes in water, feedstock, equipment, operator or laboratory method.

Review the chain from supplier release through carrier, package, receiving connection and day tank because contamination or dilution can occur after final analysis. Reconcile ordered, received, stored and consumed quantities and investigate unexplained differences. Supplier scorecards should cover documentation accuracy, delivery condition, corrective-action quality and change notification as well as price. Qualify a contingency source before disruption using the same methods and process criteria. When buyer and supplier results differ, review sample representativeness, temperature, standards, calibration, detection limits and uncertainty before deciding disposition.

Hydrochloric acid is corrosive and can release irritating hydrogen chloride vapor or acid mist. Use the current SDS, compatible materials, segregation, ventilation, secondary containment and an approved emergency plan. The NIOSH Pocket Guide entry and NIH PubChem record provide general identity and hazard context; local law, site procedures and the process hazard review remain controlling. Confirm emergency contacts, unloading hours and stop-work authority for every shipment. Close qualification with an authorized report, approved-supplier status and a defined routine-monitoring plan.

Use published research as context

A recent open-access LCD waste study evaluated pretreatment, hydrochloric-acid leaching and recovery of indium chloride. Its simulated waste mix and laboratory method require independent site validation.

Translate evidence into a site-specific qualification plan

Define the feed, equipment, analytical methods, acceptance criteria and stop conditions before trials. Scale only after replicated data, a reviewed hazard assessment and documented treatment routes support the decision.

Define the LCD feed and dismantling boundary

Separate televisions, monitors and notebooks and document model age, display technology and glass fraction. Remove lamps, electronics, films and metals through approved work instructions.

Measure indium before promising recovery

Use representative sampling and validated digestion to quantify indium, tin, iron, aluminum and other metals. Thin coatings make sampling error significant relative to total value.

Qualify glass preparation and leach selectivity

Record cutting, film removal, particle size and cleaning. Compare indium transfer with tin and matrix dissolution across representative feed lots.

Verify every separation stage

Track filtration, extraction, stripping, precipitation or crystallization as applicable. Confirm indium purity, yield and solvent losses through replicated balances.

Specify hydrochloric acid for low-level recovery

Define concentration, metals, residue, sulfate and analytical methods. Trace contaminants can matter when the target metal is present at a relatively low level.

Control water and reagent blanks

Analyze water, filters, vessels and reagents for background indium and interfering metals. Use blanks, standards and retained samples to distinguish process recovery from contamination.

Engineer compatible closed processing

Review reactor, ultrasonic equipment if used, seals, pumps, filters and extraction equipment for chloride service. Control aerosols, solvent vapor and incompatible materials with ventilation, interlocks and containment.

Characterize the cleaned glass and residues

Determine whether the remaining glass meets a reuse or disposal route. Account for polymer films, metals, spent solvent, wash water and any hazardous fractions separately.

Scale acid supply to verified net demand

Start with documented trial lots and move to larger packages only after stable preprocessing and recovery balances. Require COA, SDS, lot genealogy, retained samples and change control.

Prepare an LCD-recycling inquiry

Provide concentration, impurity limits, package, trial volume, destination and documentation needs. Review the Hiacid hydrochloric acid product page, then request a qualification quotation.

Related hydrochloric acid resources

• Hydrochloric Acid for Chitin and Chitosan Demineralization
• Hydrochloric Acid for Phosphorus Recovery from Municipal Sludge
• Hydrochloric Acid for Nickel Laterite Leaching Trials

Frequently asked questions

Why is LCD dismantling part of acid qualification?

Films, electronics, lamps, adhesives and glass preparation change feed composition, safety and reagent demand.

Why use analytical blanks?

Indium levels can be low, so background contamination from water, filters or vessels can distort recovery results.

Is indium leaching the final recovery step?

No. Selective separation, purification and product-quality verification are still required.

Can all display glass use one process?

No. Device type, age, coating, dismantling and particle preparation require representative validation.