The concept of sustainable phosphorus is studied in depth around the world, as the scientific community largely agrees that the non-renewable phosphorus reserves in the form of phosphorite ore must be used judiciously. Unfortunately, many developed countries, including Canada, have yet to implement a phosphorus management plan. The Netherlands, Germany, and Switzerland can be heralded as success stories of effective, committed, cross-sector phosphorus management. We examine factors that contributed to their success and consider how these may be transferred to Canada. We also consider Canadian geographic and research factors and contrast the Canadian policy environment and phosphorus recycling efforts with those in the EU. Finally, we analyze active Canadian and North American phosphorus interest groups and seek to determine why their collective efforts have yet to coalesce around tangible action. Canada produces phosphorus fertilizer from imported deposits of phosphate rock. Canada produces potassium fertilizer from its rich potash mines, making it a global power in nutrient production. It is imperative that Canada earns a respected leadership role in efficient global phosphorus and potassium nutrient management and recycling.

Polyacrylamide gel electrophoresis is commonly used to characterize the chain length of polyphosphates (polyP), more generally called condensed phosphates. After separation, nonradioactive, optical polyP staining is limited to chain lengths greater than 15 monomers with toluidine blue or 4′,6‐diamidino‐2‐phenylindole. PolyP chain lengths longer than 62monomers were correlated to the shortest DNA ladders. In this study, synthetic linear polyPs (Sigma‐Aldrich “Type 45”, estimated mean length of 45 monomers), trimetaphosphate (trimetaP: 3 ring), tripolyphosphate (tripolyP), pyrophosphate (PP_i), and inorganic orthophosphate (o‐P_i) were visualized after separation by an in situ hydrolytic degradation process to o‐P_i that was subsequently stained with methyl green. Statistically insignificant migration reduction of synthetic short‐chain polyP after perchloric acid or phenol–chloroform extraction was confirmed with the Friedman test. ³¹P diffusion–ordered NMR spectroscopy confirmed that extraction also reduced PP_i diffusivity by <10%. Linear regression between the R_f peak migration value and the logarithm of synthetic polyP molecular weights enabled estimation of extracted polyP chain lengths from 2 to 45 monomers. Linear polyP extracts from Saccharomyces cerevisiae grown in aerobic conditions were generally shorter than extracts cultured in anaerobic conditions. Extractions from both aerobic and anaerobic S. cerevisiae included tripolyP and o‐P_i, but no PP_i.

Municipal biosolids contain organic and inorganic phosphorus (P) that could be recovered for reuse as P fertilizer. Inorganic P compounds include iron phosphates that precipitate and/or adsorbed phosphate ions as a consequence of soluble iron addition in order not to exceed total phosphorus (TP) emission limits. The inorganic orthophosphate (o-Pi) minerals within biosolids can have low solubilities. One P recovery strategy is to maximize the dissolution of o-Pi from biosolids for reuse. Dissolving iron phosphates in biosolids by adding sodium sulfide was assessed as an o-Pi dissolution strategy. 10 % w/w biosolids slurries with a total phosphorus (TP) of 0.97 ± 0.03 mmol P/dry g were mixed with sulfide/TP (S^2-/TP) molar ratios from 0 to 4 for up to 96 h. The maximum o-Pi concentration (48 ± 7 mM, or 42 ± 6 % of TP) was obtained for 4 S^2-/TP after 24 h at room temperature (RT). Iron concentrations measured by colorimetry (ferrozine) reduced from 0.6 ± 0.1 mM to less than 0.01 mM (S^2-/TP > 1). X-ray diffraction and FTIR suggest that sulfide treatment preferentially dissolved amorphous o-Pi-containing solids, vivianite, and minerals with iron, aluminum, phosphate, sulfate, and other subsitutions. Poorly crystalline erdite (NaFeS₂ ·2H₂O) was detected in products after S^2-/TP treatment ratios ≥ 2. Incubation at RT or 37 °C did not affect the o-Pi concentrations for 0 or 4 S^2-/TP over 47 h. Sulfide addition could also increase the risk of construction material corrosion, and reduce the efficiency of P recovery by precipitation. There are disadvantages to using sulfide to dissolve o-Pi from biosolids as a potential P recovery process.