1. Material matrix by chemical family
Material selection for a chemical pump always starts from identification of the fluid family. There is no universal pump that serves all industrial chemistry — a cast iron that perfectly resists an alkaline solution at 60 °C may suffer accelerated corrosion in contact with dilute sulfuric acid, and a 316L that serves weak organic acids well may fail in weeks in a concentrated chloride environment.
The table below summarizes the most frequent combinations in the Brazilian chemical sector and the material recommendation for FBCN in each case.
| Chemical family | Typical examples | FBCN material | Sealing |
|---|---|---|---|
| Dilute sulfuric acid (<15%) | Battery, mild pickling | 316L / CF8M | Plan 53A double seal |
| Concentrated sulfuric acid (>80%) | Fertilizer, heavy chemistry | Carbon steel or duplex 2205 | Double seal + external flush |
| Hydrochloric acid (any conc.) | Pickling, chemical synthesis | or lined | Double seal with inert barrier |
| Phosphoric acid | NPK fertilizer | 316L / duplex 2205 | Plan 53B double seal |
| Caustic soda (NaOH 30-50%) | Bayer alumina, pulp and paper | 316L / 904L for high temp | Double seal + EPDM/PTFE |
| Organic solvents (toluene, xylene) | Synthesis, lacquers, paints | Cast iron or 316L (ATEX) | Double seal + FKM/PTFE |
| Polymers in solution | Resins, adhesives, polymers | 316L + open impeller | Double seal with heated jacket |
| Pharma APIs in process | Active synthesis, purification | 316L with sanitary finish | GMP sanitary seal |
2. Inorganic and organic acids: critical material boundary
Inorganic acids — sulfuric, hydrochloric, nitric, phosphoric, hydrofluoric — are the most challenging fluids for material selection. Behavior strongly depends on concentration and temperature, and the recommendation can change drastically as a function of a few Celsius degrees or a few concentration percentage points.
Sulfuric acid is a classic example: at 98% at ambient temperature, it can be pumped in common carbon steel (the passive iron sulfate layer protects the metal); at 50% at the same temperature, carbon steel corrosion is catastrophic and the recommendation drops to 316L or duplex; at higher temperature, even 316L fails and the recommendation migrates to or higher alloys.
Organic acids — acetic, formic, lactic, citric, oxalic — are generally less aggressive than inorganic ones at the same concentration, but still require 316L in most cases. The critical exception is formic acid at elevated concentrations and temperatures above 60 °C, which attacks 316L even in moderate dilutions — in these cases, the recommendation migrates to 904L or .
For the food industry, selection is similar to pharmaceutical: electropolished 316L with sanitary finish Ra <0.8 μm, no threads in contact with product, and integrated CIP (Clean-in-Place).
3. Volatile organic solvents and ATEX classification
Pumping volatile organic solvents — toluene, xylene, hexane, ethyl acetate, isopropyl alcohol, ether — is dominated by two simultaneous concerns: construction material corrosion (typically moderate for most clean solvents) and safety in explosive atmospheres. All the cited solvents have low flash point and form explosive mixtures with air at small concentrations, which requires operation in Zone 1 or Zone 2 classified areas per NBR IEC 60079-10-1.
Mandatory certification in Brazil is INMETRO per Ordinance 179/2010 — European ATEX does not replace it, although it is technically equivalent.
FBCN in organic solvent service normally gets cast iron or 316L casing, closed impeller, Ex d IIB T3 motorization for most solvents (Ex d IIC T3 for hydrogen and acetylene), anti-spark coupling, equipotential grounding and Ex ia (intrinsically safe) instrumentation. The mechanical seal needs double seal Plan 53A or 53B with inert barrier fluid (glycol or non-reactive lubricating oil), silicon carbide faces and FKM or PTFE elastomer depending on the specific chemical compatibility of the solvent.
FB Bombas supplies the complete set already INMETRO-certified with WEG or Siemens motorization, directly meeting compliance requirements of classified areas.
4. Polymers, resins and thermal oil loops
Brazilian polymer and resin manufacturing is dominated by Braskem (polyethylene, polypropylene, PVC, chlorine-soda) and Unigel (styrene, caprolactam), with a constellation of smaller producers in epoxy, polyurethane, polyester and specialty resins. The manufacturing process for these products involves chemical reactions at high temperatures (200 to 350 °C), often with increasing viscosity as the polymer forms.
The typical architecture of a polymer plant includes: mechanically agitated reactors heated by thermal oil, monomer feed lines (often volatile), jacket cooling lines and transfer lines for the final product to storage or pellet.
This is an environment where the three FB Bombas lines combine: FBCN for monomers and cooling circuits (316L or duplex depending on chemistry), FBE for partially polymerized products with increasing viscosity (positive displacement maintains stable flow even as viscosity varies 10x over the cycle), and FBOT for the reactor thermal oil heating loop (temperatures of 280 to 320 °C).
Integrating the three technologies is a competitive differentiator: the same pump-house serves the complete line, with the same engineering support and the same standardized maintenance cycle.
5. Pharmaceutical industry: GMP, ANVISA and sanitary finish
The Brazilian pharmaceutical industry is regulated by ANVISA (National Health Surveillance Agency) under Resolution RDC 658/2022, which adopts Good Manufacturing Practices (GMP) per the international PIC/S standard.
From a pump standpoint, the two practical consequences are: first, all pumps in direct contact with pharmaceutical product in process need to be of sanitary construction, with electropolished finish Ra <0.8 μm (ideal <0.4 μm), without threads or crevices that could accumulate product, and with tri-clamp or similar sanitary connections; second, cleaning validation (CIP — Clean-in-Place) must meet verification protocols by swab or rinse analysis, which forces the pump design to be compatible with automated CIP cycles.
FB Bombas meets Brazilian pharmaceutical demand with sanitary variants of the FBCN line in electropolished 316L, validated for operation in Class C/D cleanrooms and compatible with CIP with caustic soda, hydrogen peroxide or peracetic acid. FAT/SAT qualification documentation, material certificates (MTR), surface roughness testing and the complete traceability dossier are provided with each pump.
Brazilian customers in the sector — EMS, Eurofarma, Aché, Hypera Pharma, Libbs, Cristália, Biolab, Sanofi Brasil, Roche Brasil, among others — have their own specific requirements that are met case by case by the application engineering department.
