There are point sources (domestic, agricultural, and industrial wastewater) and non-point sources that pollutes Philippines’ bodies of water

Around 2.2 million metric tons of organic pollutions are produced annually affecting health, making water unfit for drinking, threatening biodiversity, and damages the Philippine economy.

Annual Renewable Water Resources

Wastewater treatment facilities are expensive and require a large area. Thus, it is currently inaccessible to most polluted waters in the Philippines

BN has partially ionic bonding (stronger compared to covalent bonding in graphene) that makes it mechanically robust, thermoconductive, and insulating.

BN can be used as absorbent in water treatment for it does not absorb water and is chemically stable. Also, it can be reused due to its thermal stability.

A study lead by Lei was able to produce porous hexagonal BN nanosheets that can absorb organic compounds 33 times its own weight.

They tested the porous BNNS on organic solvents, oils, and dyes. And it is shown that it has superior absorption capacity and can be reused through burning or heating.

A study lead by Li was able to produce activated BN that can absorb metal ions and organic contaminants in water and volatile organic compounds in air.

The activated BN has superior absorption capacity compared to both porous BN and activated carbon. Also, reusing the activated BN only lead to a slight decrease in the absorbance capacity

One of the objective of this study is to synthesize BNNS using a simple that involves only heating a boron and nitrogen containing precursor

BN powder is then washed with diluted hydrochloric acid, deionized water, and ethanol. Then dried at 80 °C for 3 h. The powder was then sonicated in IPA (3 mg/ml) for 6 h

Four methods were used to produce the boron nitride powder in the study

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Only urea-boric acid complex was formed in Method 1 but no BN product. Method 2 produces black and white flakes. Method 3, magnesium catalyst is hard to remove. Only Method 4 produces white powder

Only urea-boric acid complex was formed in Method 1 but no BN product. Method 2 produces black and white flakes. Method 3, magnesium catalyst is hard to remove. Only Method 4 produces white powder

No products were formed in Method 1. However, Methods 2, 3, and 4 have a percent yield higher than 100% and it thus suspected that there are plenty of by-products present.

The peak present at 1365 cm−1 represents the B—N—B in-plane bonding while the peak at 780 cm−1 represent secondary absorption of the bond.

The SEM images of synthesized BN powder show that the product has flake morphology and is nonporous.

AFM image of the BNNS shows that the thinnest sheet is around 5 nm, which is equivalent to 16-28 layers of h-BN., while the thickest sheet is around 85 nm.

For the dye absorption, 25 mL of 0.10 mM of orange II or methylene blue is treated with 10 mg BN powder, BNNS, or activated carbon for 2 hours under constant stirring

After 2 hours, there is minimal absorption of both the BN powder and BNNS compared to activated carbon and established absorption capacity

UV-Visible spectrum of orange II shows that the most efficient is the activated carbon followed by BNNS and BN, respectively.

Same with observations is seen in methylene blue. The most efficient is still the activated carbon followed by BNNS and BN, respectively.

Despite the low absorption, the dye is strongly adsorbed on the surface of both BN powder and BNNS and cannot be removed by water. It is also reusable after heating it.

BN powder, nonporous BNNS, and porous BNNS have different absorption capacities because of the difference in available surface area. Also, porous BNNS adsorb compounds fastest because of additional pore filling processes.

Comparing the BNNS produced from the BNNS produced by Lei’s group it is nonporous and thicker. Also, looking at the very high percent yield, it is suspected that the produced BNNS has by-products incorporated with BNNS.

2𝐵(𝑂𝐻)3 ∆𝐵2𝑂3 + 3𝐻2𝑂

𝐶𝑂(𝑁𝐻2)2 ∆𝑁𝐻3 + 𝐻𝑁𝐶𝑂

𝐵2𝑂3 + 2𝑁𝐻3 ∆2𝐵𝑁 + 3𝐻2𝑂

2𝐶𝑂 𝑁𝐻2 2 + 𝑁𝑎𝐵𝐻4 𝐵𝑁 + 𝑁𝑎𝐶𝑁 + 2𝑁𝐻3+ 𝐶𝑂2 + 3𝐻2

𝑁𝐻4𝐶𝑙 𝑁𝐻3 + 𝐻𝐶𝑙

2𝐻3𝐵𝑂3 𝐵2𝑂3 + 3𝐻2𝑂

𝐵2𝑂3 + 2𝑁𝐻3 2𝐵𝑁 + 3𝐻2𝑂

𝑀𝑔 + 2𝐻𝐶𝑙 𝑀𝑔𝐶𝑙2 + 𝐻2𝑀𝑔 +𝐻2𝑂 𝑀𝑔𝑂 + 𝐻2