Survey of methylene orange wastewater treatment by activated carbon material prepared from macadamia husk with chemical activator H3PO4 shows that coal with the best methylene orange color treatment is achieved Optimal conditions such as pH = 5, coal dose 0.9 g/L and time 120 minutes. The results show that it is applicable to color wastewater treatment and the results are similar to other research results.

Investigate the possibility of treating wastewater containing heavy metals Zn2+ with activated carbon material prepared from macadamia shell with chemical activating agent H3PO4, showing high efficiency of adsorption of Zn2+. The results of the study showed that activated carbon with H3PO4 activating agent has high adsorption capacity, capable of handling Zn2+ best at pH = 4.5, dosage 1.8 g/L and time is 120 minutes. . The results show similarities with other research results and are capable of treating wastewater containing heavy metals Zn2+.