Sodium Chloride

Product Overview

Sodium Chloride (NaCl) is the finishing shop's low-cost chloride-ion source. Its main plating job is in Watts-type nickel and nickel-iron baths, where dissolved chloride keeps nickel anodes dissolving at near 100% efficiency and raises solution conductivity. Because nickel chloride (NiCl2·6H2O) costs several times more than sodium chloride per kilogram, many shops run a blended chloride system: part nickel chloride for its nickel value, part sodium chloride for its chloride value. Beyond plating, refined salt makes the 50 g/L sodium chloride solution used for neutral salt spray testing (ASTM B117) and the brine that regenerates deionizer resin beds feeding rinse lines. In QLQ's finishing plants, salt is used in the nickel-chrome hardware lines and in the in-house salt spray cabinet that audits plated zipper sliders and buckles. Not every salt is equal for this work: vacuum-refined salt (white, ≥ 99.3%, low calcium and magnesium, no additives) is the plating-grade choice, while crude sea salt or solar salt carries calcium, magnesium, sulfate and organic residues, and common table salt may contain anti-caking agents or iodide - both of which contaminate a nickel bath.

Product Identity (Encyclopaedia Card)

What it is and what it does. Sodium chloride is the low-cost chloride source used in zinc and nickel plating baths, in pickling accelerators, and as the brine base of many cleaning and rinsing operations.

• White cubic crystals, very soluble; the chloride ion activates the anode and helps it dissolve uniformly.
• In acid zinc baths it is added together with ammonium or potassium chloride to reach the required conductivity.
• Chloride levels must be controlled in nickel baths because too much chloride causes pitting.

Typical Use in a Plating / Finishing Line

Safety, Handling & Storage

Quality Documents Shipped With Every Batch

Buyer Questions We Answer Every Week

Why Chloride Matters in a Nickel Bath (and How Much NaCl Fits)

In a Watts nickel bath the anode is the source of nickel metal, but a sulfate-only solution passivates nickel anodes and the bath starves. Chloride ions break that passivation film, and the practical rule is simple: keep total chloride (as Cl-) between roughly 12 and 20 g/L for dependable anode dissolution, and never below about 5-8 g/L or anodes film over at normal current density. Nickel chloride supplies chloride and nickel at the same time; sodium chloride supplies only chloride and sodium. On a chloride basis, 10 g/L NaCl carries about the same Cl- as 20 g/L NiCl2·6H2O, which is why a common cost-saving blend replaces roughly a third of the nickel chloride with salt. Sodium is tolerated by nickel baths in moderate amounts, but it carries no plating value, so the blended bath is controlled on total chloride by titration and on nickel metal by analysis, not by habit.

Two housekeeping notes for blended operation: sulfate and hardness impurities in crude salt build calcium sulfate scale on anodes and tank walls, and sodium that is never plated out accumulates - so keep drag-out under control and let routine carbon treatment and partial dumps manage the sodium load rather than topping the bath with salt alone forever.

How to Check Quality Before Loading a Batch

How QLQ controls it: salt is bought against a written specification that bans iodide and anti-caking additives, and every delivery is checked for appearance and clarity before the bags go into the nickel-line store. A Hull cell panel run on each new lot confirms the salt is electrically clean before it is used for production, and the lot number is logged against the tank record for traceability.

Common Problems & Fixes (Workshop Table)

Handling & Safety for the Plating Line

• Health: sodium chloride is a mild irritant only. Dust from handling bags can irritate eyes and airways - wear a dust mask and goggles when emptying bags in enclosed areas.
• Solution preparation: salt dissolves quickly in warm water with stirring; a 50 g/L salt spray solution is made up in DI water, not tap water, so calcium and magnesium do not distort the test.
• Corrosion: salt brine is aggressively corrosive to carbon steel racks, bus bars and concrete floors. Rinse spills promptly and keep the salt storage area dry and off the floor.
• Storage: keep bags sealed on pallets. Salt absorbs moisture and cakes, and a caked bag breaks open - not a safety hazard, but it makes weighing inaccurate.
• Contamination discipline: keep the plating salt physically separate from table salt and crude salt stores. Color-coded bags and a clear label prevent the classic mix-up that ruins a nickel bath.

What It Does on Iron, Zinc Alloy, Copper and Stainless Steel Parts

FAQ

Cutting nickel-line cost without cutting quality? QLQ engineers help customers blend chloride sources, set titration schedules and audit salt spray cabinets across 10+ countries. Contact us with your bath analysis.