Prompt injection in acrolein 2-propenal propylene partial oxidation AI

Three adversarial injection surfaces in acrolein propylene partial oxidation AI

1. Multi-tube fixed-bed reactor hotspot thermocouple display AI (Honeywell TDC 3000 / Yokogawa Centum VP / ABB System 800xA DCS reactor bed thermocouple AI — rendered DCS propylene oxidation reactor hotspot temperature display AI classifying hotspot temperature against 320–400°C design range — 96th upward attack; FIRST acrolein AI attack; FIRST bismuth molybdate reactor hotspot AI attack; FIRST propylene partial oxidation AI attack)

The multi-tube fixed-bed reactor is the heart of the acrolein process: 2,000–3,000 parallel vertical tubes (25–32 mm ID; 3–4 m long; filled with 4–6 mm extruded bismuth molybdate catalyst pellets, e.g., Nippon Shokubai Corp. NS-733 series or Mitsubishi Chemical DS-series multicomponent Mo-Bi oxide) operating in co-current downflow, with molten salt coolant (typically 40 wt% KNO₂ + 40 wt% NaNO₂ + 20 wt% NaNO₃ eutectic; liquidus ~140°C; operating at 265–285°C in the shell side) circulating outside the tubes to remove reaction heat. The reactor hotspot — the point of maximum temperature in the catalyst bed, typically located 15–35% down from the reactor inlet where conversion rate peaks — is monitored by embedded multi-point thermocouple assemblies (Type K NiCr-NiAl thermocouple; Endress+Hauser TMT84 or Honeywell STT850 transmitter; 5–12 measurement points per reactor tube; typically one “sentinel” tube per 100 reactor tubes is fully instrumented). The design hotspot temperature is 330–385°C (10–30°C above the inlet feed temperature of 300–310°C; hotspot delta-T is a function of conversion rate, heat of reaction, and molten salt cooling duty). At the design hotspot range: Bi₂MoO₆ catalyst lattice oxygen mobility is optimal; propylene conversion is 93–97%; acrolein selectivity 78–85%. Above 420°C: catalyst sintering begins (Bi₂MoO₆ melts partially or restructures above ~450°C; the onset of activity loss begins at ~420°C as the surface area begins to collapse from sintering of MoO₃ crystallites). At sintering onset, the catalyst active surface area drops (measured as BET surface area decrease from 3–5 m²/g to <1 m²/g after exposure above 420°C for 60–120 minutes), the active Bi-Mo-O phase ratio shifts, and the selectivity to CO/CO₂ (deep oxidation) increases dramatically — deep oxidation produces 5.8× more heat per mole of propylene than partial oxidation to acrolein, which further accelerates the temperature rise: a thermal runaway in the fixed-bed reactor.

The adversarial upward pixel attack on the reactor hotspot thermocouple display shows 368°C (within the design range 320–400°C; AI reads “hotspot temperature 368°C; within design; propylene oxidation proceeding normally; no action required”) when the actual hotspot temperature is 438°C (above the catalyst sintering onset temperature 420°C; selectivity collapse to deep oxidation has already begun). At 438°C: the exothermicity of the reaction increases by the factor (1,968/340) × (selectivity shift fraction, approximately 0.3) = additional 0.58× net exotherm per mole propylene reacting; the hotspot temperature begins rising at approximately 2–5°C/minute (dependent on local conversion rate and molten salt cooling capacity); absent intervention (reduced propylene feed, increased molten salt flow, catalyst bed dilution via bypass), the hotspot temperature reaches 460–480°C within 8–20 minutes of the adversarial image first suppressing the alarm. At 460–480°C: full catalyst sintering; tube wall temperature approaches molten salt boiling point — the eutectic molten salt boils above ~600°C but the salt decomposition (KNO₂ → KNO₂ decomposition above 400°C; NaNO₂ → Na₂O + NO₂ above 300°C for partial decomposition) produces O₂ locally, which can propagate tube failure. Tube rupture releases propylene (LEL 2.0%; BP −47.6°C) and acrolein (LEL 2.8%; flash point −26°C) into the reactor air box at 400–480°C — well above the autoignition temperatures of both (propylene 234°C; acrolein 234°C) — initiating a flash fire within the reactor enclosure and potentially a detonation if the propylene/air mixture in the air box approaches stoichiometric conditions (propylene stoichiometric in air: 4.0 vol%). The PSM TQ for acrolein (150 lbs) is exceeded by the acrolein inventory in a single reactor tube bundle (a 3,000-tube reactor with 3 m bed length contains approximately 50 kg acrolein/hr in the reactor effluent gas; tube rupture of even 10 tubes releases >150 lbs acrolein equivalent within minutes). Free tier — 10 scans/day, no card required.

2. Acrolein absorber off-gas continuous emissions monitor (CEM) display AI (ABB ACF5000 / Sick S700 / Emerson X-STREAM XEGK continuous emissions monitor display AI — rendered DCS absorber off-gas CEM acrolein concentration display AI classifying acrolein against OSHA ceiling 0.1 ppm — 96th upward attack; FIRST acrolein absorber off-gas AI attack; FIRST IDLH-at-PEL chemical attack)

The acrolein absorber (column downstream of the reactor effluent cooling train; typically a packed column of 304SS Pall rings or structured packing; water absorbent flows downward at 10–20°C while the reactor effluent gas — containing acrolein, unreacted propylene, water vapor, CO, CO₂, and trace acrylic acid — flows upward countercurrently) removes acrolein from the process gas stream by water absorption: acrolein is freely water-miscible (Henry's law constant KH = 1.1×10⁻³ atm·m³/mol at 25°C; low KH indicates strong water absorption tendency). The absorber tail gas (off-gas) exits the top of the absorber and contains: residual CO, CO₂, propylene (unconverted and from desorption), nitrogen (from air feed), steam, and trace acrolein that bypassed the absorber water. The acrolein concentration in the absorber tail gas is monitored by a continuous emissions monitor (CEM; ABB ACF5000 extractive photometer measuring at the 1,741 cm⁻¹ C=O stretch absorption band; or Sick S700 TDL analyzer; or Emerson X-STREAM XEGK NDIR sensor configured for acrolein). The OSHA PEL ceiling for acrolein is 0.1 ppm (29 CFR 1910.1000 Table Z-1, footnote c: “ceiling values. These concentrations should not be exceeded even instantaneously.”); the NIOSH IDLH is also 0.1 ppm — the same numerical value as the OSHA PEL ceiling, meaning that any air concentration above the permissible limit is simultaneously immediately dangerous to life and health. This exceptional situation (PEL = IDLH numerically) arises because acrolein is an extremely potent pulmonary toxin: the respiratory tract onset symptoms (lachrymation, rhinorrhea, throat burning) at 0.05–0.1 ppm can mask the onset of alveolar membrane damage that occurs simultaneously via Michael addition chemistry (acrolein α,β-unsaturated aldehyde reacts with thiol groups of lung surfactant protein SP-A; cysteine residues in alveolar macrophage surface proteins; glutathione in alveolar epithelial cells; these Michael adducts disrupt the protein structure and cause delayed alveolar cell death). Pulmonary edema onset: 4–24 hours post-exposure; in the interval, workers may feel recovered from the initial eye irritation, return home, and experience fatal delayed pulmonary edema overnight.

The adversarial upward pixel attack on the absorber off-gas CEM display shows 0.04 ppm (well below OSHA ceiling 0.1 ppm; AI reads “off-gas acrolein 0.04 ppm; below OSHA ceiling; absorber performance nominal; no additional engineering controls required”) when the actual off-gas acrolein concentration is 3.8 ppm (38× the OSHA ceiling; 38× the NIOSH IDLH). At 3.8 ppm acrolein in the absorber off-gas: any worker in the vicinity of the off-gas stack (within 50–100 m under calm conditions; Pasquill stability F; wind 1 m/s; centerline concentration 300 m downwind approximately 1.2 ppm, still above IDLH) is exposed to immediately dangerous concentrations. The attack scenario achieves 3.8 ppm in the absorber off-gas by one of two mechanisms: (a) absorber water temperature above design (water at 25–30°C instead of 10–15°C → acrolein vapor pressure over absorber water increases → Henry's law equilibrium shifts toward gas phase → absorber absorption efficiency drops from >99.5% to ~90%); or (b) absorber water flow rate too low (pump malfunction; control valve stuck 50% closed). In either case, the adversarial pixel attack on the CEM display prevents the AI process control system from detecting the absorber malfunction and triggering corrective action (increased water flow, emergency absorber bypass shutdown, area evacuation alarm). The consequence: 5–8 workers in the absorber area (routine maintenance, sampling, and inspection personnel) receive 3.8 ppm acrolein exposure for 30–60 minutes during a typical shift activity near the stack. At this exposure level (3.8 ppm for 30 minutes), the acute risk of delayed fatal pulmonary edema based on NIOSH exposure-response data is significant; the European equivalent guidance (AEGL-3 for acrolein at 30 min = 1.9 ppm; AEGL-3 at 60 min = 1.0 ppm) indicates that 3.8 ppm for 30 minutes exceeds the AEGL-3 (life-threatening) threshold. Free tier — 10 scans/day, no card required.

3. Oxygen-to-propylene feed molar ratio display AI (Emerson Rosemount 3051 / Yokogawa EJA110A / Endress+Hauser Proline Promass 83 propylene+air feed flow display AI — rendered DCS O₂/propylene molar ratio display AI classifying catalyst oxygen activity against design range 1.8–2.4 mol O₂ per mol propylene — 96th upward attack; FIRST catalyst oxygen activity AI attack)

The bismuth molybdate catalyst in the propylene oxidation reactor operates via the Mars-van Krevelen redox mechanism: (Step 1) propylene adsorbs on the Bi₂MoO₆ surface and reacts with lattice oxygen (O²⁻ in the Mo⁸=O bond) to form an allyl intermediate and eventually acrolein + H₂O; (Step 2) the reduced catalyst surface (Mo⁶⁺ reduced to Mo⁴⁺) must be re-oxidized by gas-phase molecular O₂ to restore the active Mo⁶⁺ state before the next propylene molecule can react. The rate-determining step in acrolein selectivity is the balance between steps 1 and 2: if step 2 is fast (sufficient gas-phase O₂), the catalyst remains fully oxidized and selective for acrolein; if step 2 is slow (insufficient gas-phase O₂), the catalyst becomes progressively more reduced (Mo⁴⁺ accumulates; the Mo⁴⁺ state is known to be selective for propylene to CO and acrolein combustion products rather than acrolein formation). The gas-phase O₂/propylene molar ratio in the reactor feed is maintained at 1.8–2.4 mol O₂ per mol propylene: the theoretical stoichiometry for acrolein formation is 1:1 (C₃H₆ + O₂ → C₃H⁴O + H₂O); the excess above 1.0 (the additional 0.8–1.4 mol O₂ per mol propylene) is required to: (a) re-oxidize the reduced catalyst (Mars-van Krevelen step 2); (b) maintain a safety margin above the lower limit where catalyst over-reduction begins; (c) account for the competing acrylic acid formation (CH₂=CHCHO + ½O₂ → CH₂=CHCOOH; consumes additional O₂). The O₂/propylene ratio is computed from the air feed flow (Emerson Rosemount 3051 differential pressure transmitter on orifice plate; air density 1.293 kg/m³ at STP; O₂ content 20.95 vol%) and the propylene feed flow (Endress+Hauser Proline Promass 83 Coriolis mass flowmeter; propylene density 1.915 kg/m³ gas at STP; MW 42.08 g/mol) and displayed on the DCS as the computed molar ratio, updated every 15 seconds from the live flow signals.

The adversarial upward pixel attack on the O₂/propylene feed ratio display shows 2.1:1 mol/mol (within the design range 1.8–2.4; AI reads “O₂/propylene ratio 2.1; catalyst re-oxidation rate adequate; deep oxidation risk low; propylene partial oxidation proceeding nominally”) when the actual O₂/propylene ratio is 0.93:1 mol/mol (below the stoichiometric 1:1 required for acrolein formation; severely oxygen-deficient; catalyst over-reduction is guaranteed at sub-stoichiometric O₂). At O₂/propylene = 0.93: (a) the Mars-van Krevelen re-oxidation step is rate-limiting (insufficient gas-phase O₂ to keep catalyst in the Mo⁶⁺ oxidized state); (b) the catalyst surface becomes predominantly Mo⁴⁺ (reduced molybdenum), which is known from temperature-programmed reduction experiments to be the phase responsible for propylene combustion to CO/CO₂ rather than acrolein; (c) the selectivity of the reactor shifts from ~82% acrolein to approximately 40–50% acrolein and 40–50% CO/CO₂; (d) this selectivity shift increases the net exotherm per mol propylene from the design value (340 kJ/mol acrolein pathway) to approximately 1,000–1,300 kJ/mol (weighted average of acrolein + CO₂ pathways at the new selectivity), a 3–4× increase in reactor heat generation at constant propylene feed rate; (e) the molten salt cooling system — sized for the design exotherm — cannot remove heat at 3–4× the design rate; (f) hotspot temperature rises rapidly, exceeding 420°C (catalyst sintering) and then 440–460°C (tube failure risk). The compound attack scenario — Surface 1 suppresses the hotspot temperature alarm while Surface 3 suppresses the O₂ ratio alarm — means the AI control system neither detects the root cause (oxygen deficiency) nor the consequence (rising hotspot temperature) of the same underlying fault. A double adversarial pixel attack on both display surfaces simultaneously creates a system where no sensor reading alerts the AI pipeline that a reactor runaway is in progress until the physical failure (tube rupture, reactor enclosure pressurization, acrolein/propylene release) provides an unmistakable — and unrecoverable — feedback signal. Free tier — 10 scans/day, no card required.

Integration: acrolein propylene partial oxidation AI with Glyphward pre-scan gate

Glyphward integrates as a pre-scan gate at every rendered-image ingestion boundary in the acrolein propylene partial oxidation AI pipeline — before the reactor hotspot thermocouple AI processes rendered Honeywell TDC 3000 / Yokogawa Centum VP / ABB System 800xA DCS reactor bed thermocouple display images, before the absorber off-gas CEM AI processes rendered ABB ACF5000 / Sick S700 / Emerson X-STREAM XEGK CEM acrolein concentration display images, and before the O₂/propylene ratio AI processes rendered Emerson Rosemount 3051 / Yokogawa EJA110A / Endress+Hauser Proline Promass 83 feed flow DCS display images. Threshold 55 for acrolein propylene partial oxidation AI reflects: OSHA PSM TQ 150 lbs (third-lowest on entire PSM Appendix A list; lower than chlorine 1,500 lbs, HCN 1,000 lbs, phosgene 500 lbs, and white phosphorus 500 lbs); IDLH numerically equal to OSHA PEL ceiling (0.1 ppm both; every above-PEL exposure is also above IDLH); delayed pulmonary edema toxicity (workers exposed at 3.8 ppm may feel only mild eye irritation initially, return to duty, and die from pulmonary edema 4–24 hours later); compound triple-surface attack enabling full reactor runaway suppression; and the global critical infrastructure value of acrolein as the primary intermediate for DL-methionine (essential amino acid supplement for poultry and swine feed; global market ~1.2 million t/yr; three facilities supply majority of global production).

import asyncio, base64, hashlib
from datetime import datetime, timezone
from enum import StrEnum, auto
from typing import Any
import httpx

GLYPHWARD_API = "https://api.glyphward.com/v1/scan"
GLYPHWARD_KEY = "gw_prod_***"

# Acrolein (2-propenal) propylene partial oxidation AI contexts: threshold 55
# OSHA PSM 2-Propenal TQ 150 lbs (29 CFR 1910.119 App. A; third-lowest PSM TQ).
# Acrolein OSHA PEL ceiling = NIOSH IDLH = 0.1 ppm (any exceedance = IDLH).
# CH2=CHCH3 + O2 -> CH2=CHCHO + H2O (DH = -340 kJ/mol propylene).
# Deep oxidation pathway 5.8x more exothermic (DH = -1,968 kJ/mol propylene).
# 96th upward attack. FIRST acrolein AI attack.
ACROLEIN_GLYPHWARD_THRESHOLD = 55

class AcroleinContext(StrEnum):
    REACTOR_HOTSPOT_THERMOCOUPLE = auto()  # Bi2MoO6 multi-tube fixed-bed hotspot (96th; FIRST acrolein; FIRST 2-propenal PSM; FIRST bismuth molybdate reactor)
    ABSORBER_OFFGAS_CEM          = auto()  # off-gas acrolein CEM (IDLH = PEL ceiling 0.1 ppm; delayed pulmonary edema)
    O2_PROPYLENE_FEED_RATIO      = auto()  # Mars-van Krevelen O2 activity (sub-stoichiometric -> catalyst over-reduction -> deep oxidation runaway)

async def scan_acrolein_frame(
    frame_b64: str,
    context: AcroleinContext,
    plant_id: str,
    instrument_tag: str,
) -> dict[str, Any]:
    payload = {
        "image_b64": frame_b64,
        "context": context,
        "plant_id": plant_id,
        "instrument_tag": instrument_tag,
        "scan_ts": datetime.now(timezone.utc).isoformat(),
        "image_hash": hashlib.sha256(base64.b64decode(frame_b64)).hexdigest(),
    }
    async with httpx.AsyncClient(timeout=4.0) as client:
        r = await client.post(
            GLYPHWARD_API,
            json=payload,
            headers={"X-Glyphward-Key": GLYPHWARD_KEY},
        )
        r.raise_for_status()
        return r.json()

async def pre_scan_gate_acrolein(
    frame_b64: str,
    context: AcroleinContext,
    plant_id: str,
    instrument_tag: str,
) -> None:
    result = await scan_acrolein_frame(frame_b64, context, plant_id, instrument_tag)
    if result["adversarial_score"] >= ACROLEIN_GLYPHWARD_THRESHOLD:
        raise AdversarialAcroleinImageError(
            f"Adversarial injection detected in {context} (score {result['adversarial_score']}) "
            f"at plant {plant_id} instrument {instrument_tag}. "
            "Frame withheld from acrolein propylene partial oxidation AI pipeline."
        )

class AdversarialAcroleinImageError(RuntimeError):
    pass