Cyanide — Equipment Material Selection

Name: Cyanide Equipment Material Selection Dataset
Creator: James Riggins

Direct answer: This page collects every published row in the LibertyCES datasets that applies to cyanide service: Flowline chemical compatibility chart, elastomer seal compatibility, centrifugal pump material resistance, peristaltic tube compatibility, hydrometallurgical duty-class selection, engineering rules. This page collects the sodium, potassium, calcium and copper cyanide entries from each dataset. Other cyanide compounds in those datasets (for example barium, cadmium, nickel, silver, zinc, mercuric) are not repeated here; see the related links and the full dataset pages. LibertyCES supplies the equipment for handling these fluids, never the fluid itself.

Pipe, Tank & Wetted Material Compatibility

Sodium Cyanide (Solution)

Concentration	Temp (°F)	Temp (°C)	PVC	Polypropylene (PP)	PVDF	PFA	PTFE	Stainless Steel 316
—	104	40	Excellent	Excellent	Excellent	Excellent	Excellent	Excellent
—	176	80	No rating published	Good	Excellent	No rating published	Excellent	Fair

Potassium Cyanide

Concentration	Temp (°F)	Temp (°C)	PVC	Polypropylene (PP)	PVDF	PFA	PTFE	Stainless Steel 316
—	176	80	No rating published	Good	Excellent	No rating published	Excellent	Good
—	104	40	Excellent	Excellent	Excellent	Excellent	Excellent	Good

Copper Cyanide

Concentration	Temp (°F)	Temp (°C)	PVC	Polypropylene (PP)	PVDF	PFA	PTFE	Stainless Steel 316
—	176	80	No rating published	Good	Excellent	No rating published	Excellent	Good
—	104	40	No rating published	Excellent	Excellent	Excellent	Excellent	Good

Legend: E = Excellent · G = Good · F = Fair · C = Corroded · (blank) = No rating published for this chemical/concentration/temperature combination — treat as unknown, not safe · A = Rating code not defined in the source vendor legend (appears once, Ammonium Sulfate/316SS) — shown as-is, not interpreted. Blank ratings mean no rating was published. Source: Flowline chemical compatibility chart.

Elastomer Seal Material Compatibility

Dataset entry	FFKM	FKM-ETP	TFE/P	FKM	HNBR
SODIUM CYANIDE	Good	Good	Good	Good	Good
POTASSIUM CYANIDE	Good	Good	Good	Good	Good
CALCIUM CYANIDE	Good	Good	Good	Good	Good
COPPER CYANIDE	Good	Good	Fair	Good	Good

Ratings: 1 = Good, 2 = Fair, 3 = Poor, 4 = Not Recommended. Full dataset: Elastomer Seal Material Compatibility.

Centrifugal Pump Wetted-End Material — Max Temperature (°F)

Dataset entry	Sp. Gr.	CPVC	Glass-Filled PP	PVDF	Ryton PPS	ETFE	PTFE	316 SS	Hastelloy C-276	Titanium	Carbon	Ceramic	Silicon Carbide	EPDM	FKM	FEP
Sodium Cyanide NaCN	—	180	180	275	70	300	500	140	200	200	500	500	500	176	176	300
Potassium Cyanide KCN	—	180	180	285	200	300	500	140	140	200	500	NR	500	200	70	300

"NR" = not recommended at any temperature, "ND" = no data published. Full dataset: Centrifugal Pump Material Resistance.

Peristaltic Pump Tube Compatibility

Dataset entry	Flex-A-Prene®	Flex-A-Chem®	Flex-A-Thane®
Sodium Cyanide, 30% in w	Excellent	Excellent	Not Recommended
Potassium Cyanide, 33% in w	Excellent	Excellent	Excellent

Based on 28-day room-temperature (73°F) immersion testing. Full dataset: Peristaltic Pump Tube Compatibility.

Hydrometallurgical Duty-Class Material Selection

Service context	Fluid	Concentration	Max temp (°F)	Equipment	Material	Verdict
Leaching Control Skid manifold (gold/silver circuit)	Barren Cyanide Solution	not stated	100	Skid / Manifold	Polypropylene + SST316	Recommended

Leaching Control Skid manifold (gold/silver circuit) — Polypropylene + SST316: Real, named dual-chemistry rating -- the same skid family is rated for both major heap-leaching chemistries (copper SX/EW raffinate and gold/silver cyanide). (Source: Netafim Mining Products catalog (Leaching Control Skid))

Full dataset: Hydrometallurgical Duty-Class Material Selection.

Equipment by Process Stage

Cyanide Destruction / Precipitation (gold/silver route)

Process: Two-stage pH/ORP-controlled process: cyanide -> cyanate -> carbonate, with an explicit cyanogen chloride gas hazard if pH isn't raised fast enough (target under 0.1 ppm).

Equipment class: pH/ORP instrumentation, dosing pumps, reaction tanks

GF Signet -- cyanide destruction process knowledge (2-stage pH/ORP setpoints), electrode selection for cyanide-poisoning-resistant service
ProMinent -- metering pumps for reagent dosing

Source: existing rules cyanide-destruction-ph-orp-setpoints, ph-orp-electrode-poisoning-ion-selection. Full dataset: Leach-Circuit Equipment by Process Stage.

Engineering Rules That Apply

Cyanide Destruction Ph Orp Setpoints

Cyanide is an extremely toxic complexing agent widely used in plating processes. The two-stage method (cyanide to cyanate, then cyanate to carbonate/nitrogen gas) is the nationally preferred treatment approach; some jurisdictions accept single-stage (batch) treatment. These are real, vendor-published process control setpoints and explicit gas-release safety hazards, not general industry knowledge.

Confidence: confirmed. Source: vendor-sources/gf-signet-application-solutions.md.

Ph Orp Electrode Poisoning Ion Selection

Signet's own published pH/ORP Electrode Application Matrix rates its general-purpose 2724-2726/2734-2736 electrode families only '**' (Compatible, the lowest non-excluded tier) against every one of these poisoning chemicals, while the Harsh Chemicals family (2764-2767) rates '*****' (Better) against the identical list. This is not a hard compatibility cutoff (general-purpose electrodes will technically function) but a real electrode-life/reliability distinction - continuous exposure to silver-ion-reactive or heavy-metal chemistries will foul or poison a general-purpose electrode's reference junction faster than the harsh-chemical-rated version. Directly relevant to any cyanide destruction (see cyanide-destruction-ph-orp-setpoints) or chrome reduction (see chrome-reduction-ph-orp-setpoints) system quote, since both processes generate exactly these poisoning ions in the monitored stream, and to any plating-bath wastewater treatment quote generally.

Confidence: confirmed. Source: vendor-sources/gf-signet-instrumentation-catalog.md.

Equipment LibertyCES Supplies

LibertyCES specifies and supplies the pumps, valves, tanks, piping, and instrumentation that store, transfer, meter, and contain fluids like cyanide — never the fluid itself, always the equipment engineered to handle it.

Reviewed by James Riggins, Founder, LibertyCES — 30+ years specifying industrial fluid-handling equipment. Request a free spec review →

This data is a screening reference, not a final engineering approval; confirm with a manufacturer-specific data sheet before specifying equipment. Blank or "No data" entries mean no rating was published — treat as unknown, not safe.

All chemicals →
All engineering rules →

Frequently Asked Questions

Does LibertyCES sell cyanide?

No. LibertyCES supplies the equipment that stores, transfers, meters, and controls fluids like cyanide (pumps, valves, tanks, piping, instrumentation). It does not supply the fluid itself.

Which engineering rules apply to cyanide service?

Published rules on this page: Cyanide Destruction Ph Orp Setpoints; Ph Orp Electrode Poisoning Ion Selection. Each links to its full rule page with confidence rating and source.

Is this data a final material approval for cyanide?

No. It is a screening reference compiled from published vendor data and LibertyCES field rules. Ratings depend on concentration and temperature; confirm against the manufacturer data sheet and your actual duty point, or request a free spec review.

Source: Liberty Chemical Equipment & Supply, Inc. (LibertyCES) — engineering data compiled and reviewed by James Riggins, Founder, LibertyCES, from real vendor and field-verified sources. For a free spec review, call James at (559) 395-5500 or email james@libertyces.com / sales@libertyces.com. Website: libertyces.com.