Sulfite Nanoparticle Oxygen Scavenging (2D)

Antioxidant Load

Sulfite nanoparticle dose 30

Temperature 25 °C

O₂ influx rate 12 /s

Time scale 1.0×

Live Readouts

Sulfite remaining

100%

O₂ scavenged

Target spoiled (oxidized)

0 / 24 (0%)

Sulfite nanoparticle (active surface sites) Spent nanoparticle (sulfate-coated) Dissolved O₂ molecule Protected target compound Oxidized / spoiled target

How it works

Sulfite salts (SO₃²⁻) are the working antioxidant in wine, dried fruit and cured meat: dissolved oxygen oxidizes sulfite before it can oxidize the food's pigments, vitamins or fats.

Net reaction:  2 SO3^2-(surface) + O2 -> 2 SO4^2-
Rate law:      rate = k(T)·[SO3^2-]·[O2]     (2nd order)
Arrhenius:     k(T) = k_ref·exp(-(Ea/R)·(1/T - 1/T_ref))
Diffusion (Stokes-Einstein, ratio form):
  D(T) = D_ref·(T/T_ref)·(eta(T_ref)/eta(T))
water viscosity (Vogel-Fulcher-Tammann eq.):
  eta(Tc) = 2.414e-5 · 10^(247.8/(Tc+133.15)) Pa·s

Sulfite dose — how many nanoparticles (and therefore how many reactive SO₃²⁻ surface sites) are seeded in the batch. Each nanoparticle carries a finite capacity; once exhausted it turns grey and stops reacting.
Temperature — raises both the Arrhenius reaction rate k(T) (faster sulfite consumption per collision) and the diffusion coefficient D(T) (O₂ molecules random-walk faster and reach nanoparticles or targets sooner) — the real reason warm storage burns through a sulfite dose faster.
O₂ influx — new dissolved-oxygen molecules entering from the headspace/packaging per second, modelling permeability of the container.
An O₂ molecule that reaches an active nanoparticle reacts with probability 1−e^−k(T)·dt and is consumed, depleting one surface site. An O₂ molecule that instead reaches an unprotected target compound oxidizes it permanently (browning/spoilage). Once every nanoparticle is spent, incoming O₂ passes straight through to the targets — this is why a sulfite dose has a finite protective lifetime.
This is a top-down 2D cross-section of the same solution volume — drag to pan, scroll/pinch to zoom. A live chart below tracks sulfite remaining, cumulative O₂ scavenged and spoilage over time.

t = 0.0 s

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