DEVELOPMENT OF COD (CHEMICAL OXYGEN DEMAND) ANALYSIS METHOD IN WASTE WATER USING SPECTRODIRECT

Increased human activities will cause various problems, one of which is water pollution in water sources because it receives a pollution load that exceeds its carrying capacity. In the context of environmental conservation, the government has set quality standards for liquid waste produced by various industries and other activities in a Decree of the State Minister for the Environment. COD (Chemical Oxygen Demand) is one of the most important parameters in wastewater quality standards. This study aims to validate the COD analysis method which refers to COD Thermoreactor System (LOVIBOND brand) at Pakuan University Service Laboratory, to ensure the validity of COD analysis results at Pakuan University Service Laboratory. Spectrodirect COD analysis method provides results that meet the requirements of accuracy, precision, LOD, and LOQ which is quite good. The results of the Coefficient of Variation give good results with a value of 1.8841% indicating the accuracy of the analysis method is good. The accuracy parameter also gives good results and meets the requirements with a% recovery value of 98.70351%. Overall, it can be stated that the spectrodirect analysis method tested is an accurate, precise, simple, and economical method for determining COD levels

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Pengolahan Limbah Cair Industri Pakan Ternak dengan Kombinasi Proses Aerasi dan Biologi Aerob

Jurnal Teknologi Lingkungan ◽

10.29122/jtl.v22i2.3967 ◽

2021 ◽

Vol 22 (2) ◽

pp. 249-256

Author(s):

Ketut Sumada ◽

Novika Cahya Chaerani ◽

Melandy Dwi Priambodo ◽

Erwan Adi Saputro

Keyword(s):

Chemical Oxygen Demand ◽

Animal Feed ◽

Oxygen Demand ◽

Quality Standards ◽

Biological Oxygen Demand ◽

Integrated System ◽

Inorganic Substances ◽

Study Results ◽

Wastewater Quality ◽

Aeration Process

ABSTRACT Wastewater is unclean and contains various substances that can risk the lives of humans and animals. This waste usually comes from the results of human actions (including industrialization). Industry must apply the principle of waste control in a careful and integrated system. Aeration is one of the most widely used techniques for improving the physical and chemical characteristics of wastewater. The aerobic microbiological wastewater treatment process utilizes aerobic microbial activity in aerobic conditions to decompose organic matter in wastewater into stable inorganic substances that don’t provide pollution impacts on the environment. This study determines the best time for the aeration process to reduce Chemical Oxygen Demand (COD) or Biological Oxygen Demand (BOD) of animal feed wastewater and the volume ratio of waste, that is, the number of microorganisms to reduce COD and BOD of animal feed wastewater. The study results show that the longer the aeration contact time, the more significant the decrease in COD and BOD values. In addition, the greater the addition of microbial concentration, the more effective the reduction in COD and BOD values. Furthermore, the aeration process time with microbial concentration, which will produce the best COD and BOD reduction, is 6 hours. Unfortunately, the COD and BOD values ??still do not meet the wastewater quality standards in the aeration process. Still, with microbial concentrations, COD and BOD values ??reduction targets will be obtained in the aerobic biological process, following the wastewater quality standards. Finally, wastewater processing from the animal feed industry with a combination of aeration and aerobic biology can meet quality standards. Keywords: aerobic, anaerobic, animal feed, BOD, COD, wastewater ABSTRAK Air limbah merupakan air yang tidak bersih atau yang mempunyai kandungan berbagai zat yang berbahaya bagi kelangsungan hidup manusia, hewan, dan tumbuhan. Biasanya limbah dihasilkan dari kegiatan manusia (termasuk industrialisasi) sehingga sudah sepatutnya perindustrian mengelola hasil buangannya sesuai kaidah pengolahan limbah secara terpadu, efisien, dan efektif. Aerasi merupakan salah satu teknik yang paling banyak digunakan dalam perbaikan karakteristik fisik dan kimiawi air limbah. Terdapat berbagai proses pengolahan limbah di mana salah satunya dengan memanfaatkan aktivitas mikroba aerob untuk menguraikan zat organik dalam kondisi aerob menjadi zat anorganik yang stabil yang tidak mencemari lingkungan. Tujuan dari penelitian ini adalah mengetahui waktu terbaik proses aerasi terhadap penurunan Chemical Oxygen Demand (COD) atau Biological Oxygen Demand (BOD) limbah cair pakan ternak dan mengetahui rasio volume limbah, yaitu jumlah mikroorganisme terhadap penurunan COD dan BOD limbah cair pakan ternak. Kesimpulan hasil kajian yaitu waktu pengontakan aerasi semakin lama dan penambahan konsentrasi mikroba berpengaruh pada penurunan nilai COD dan BOD dengan penurunan terbaik didapatkan pada waktu 6 jam. Nilai COD dan BOD proses biologi aerob dengan penambahan konsentrasi mikroba pada proses aerasi dan kombinasi aerasi dan biologi aerob telah memenuhi standar baku mutu limbah tetapi pada proses aerasi belum. Kata kunci: aerob, anaerob, BOD, COD, limbah cair, pakan ternak

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Pengukuran Parameter Bahan Organik Di Perairan Sungai Silugonggo, Kecamatan Juwana, Kabupaten Pati

BULETIN OSEANOGRAFI MARINA ◽

10.14710/buloma.v10i3.32345 ◽

2021 ◽

Vol 10 (3) ◽

pp. 299-306

Author(s):

Erick Samuel Frederico Hasibuan ◽

Endang Supriyantini ◽

Sunaryo Sunaryo

Keyword(s):

Organic Matter ◽

Chemical Oxygen Demand ◽

Biochemical Oxygen Demand ◽

Oxygen Demand ◽

Quality Standard ◽

Parameter Analysis ◽

Fishing Industry ◽

Total Organic Matter ◽

Purposive Sampling ◽

Wastewater Quality

Perairan Silugonggo merupakan area pemukiman warga dengan banyak aktivitas perikanan dan kelautan seperti: pertambakan, industri perikanan dan merupakan alur pelayaran. Tingginya aktivitas pemukiman dan industri akan menghasilkan limbah organik dalam jumlah besar. Bahan organik yang melimpah dapat menimbulkan pencemaran lingkungan. Penelitian ini bertujuan untuk mengetahui kandungan bahan organik di perairan sungai Silugonggo, Kecamatan Juwana, Kabupaten Pati. Kandungan bahan organik diketahui melalui analisis parameter TOM (Total Organic Matter), BOD5 (Biochemical Oxygen Demand) dan COD (Chemical Oxygen Demand). Pengambilan sampel dilaksanakan pada tanggal 20 Desember 2019 dan 20 Januari 2020. Metode yang digunakan pada penelitian ini menggunakan metode kasus dengan pengamatan secara langsung di lapangan dan penentuan lokasi penelitian menggunakan metode purposive sampling. Hasil pengukuran parameter penelitian dianalisis menggunakan analisis ragam. Hasil penelitian menunjukkan bahwa nilai TOM sebesar 8,11 – 11,9 mg/L. Hasil pengukuran parameter (a) BOD5 sebesar 8,07 – 24,66 mg/L dan (b) COD sebesar 26,04 – 79,21 mg/L, hasil tersebut berada di bawah baku mutu yang ditetapkan menurut Keputusan Menteri Lingkungan Hidup No. 51 Tahun 2004 tentang Baku Mutu Air Limbah. Tingginya nilai TOM dikarenakan banyaknya masukan limbah bahan organik dari aktivitas di perairan sungai Silugonggo, seperti: pertambakan, industri perikanan, dan alur pelayaran. Silugonggo waters is a residential area with many fishery and marine activities such as: aquaculture, fishing industry and shipping lanes. High residential and industrial activities will produce large amounts of organic waste. Abundant organic matter can cause environmental pollution. This study aims to determine the content of organic matter in the waters of the Silugonggo River, Juwana District, Pati Regency. The content of organic matter is known through parameter analysis of TOM (Total Organic Matter), BOD5 (Biochemical Oxygen Demand) and COD (Chemical Oxygen Demand). Sampling was carried out on December 20, 2019 and January 20, 2020. The method used in this study used the method of direct observation in the field and the date of the research location using the purposive sampling method. The results of the measurement of research parameters were analyzed using analysis of variance. The results showed that the TOM value was 8.11–11.9 mg/L. Parameter measurement results (a) BOD5 of 8.07–24.66 mg/L and (b) COD of 26.04–79.21 mg/L, these results are below the quality standard stipulated according to the Decree of the Minister of the Environment No. 51 of 2004 concerning Wastewater Quality Standards. The high value of TOM is due to the large number of inputs of organic matter from activities in the waters of the Silugonggo river, such as: aquaculture, fishing industry, and shipping lanes.

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Evaluation Methods of Water Environment Safety and Their Application to the Three Northeast Provinces of China

Sustainability ◽

10.3390/su11185135 ◽

2019 ◽

Vol 11 (18) ◽

pp. 5135 ◽

Cited By ~ 2

Author(s):

Li ◽

Sun ◽

Yuan ◽

Liu

Keyword(s):

Principal Component Analysis ◽

Water Resources ◽

Chemical Oxygen Demand ◽

Water Environment ◽

Oxygen Demand ◽

Principal Component ◽

Component Analysis ◽

Analysis Method ◽

Industry Output ◽

Per Capita

Focusing on the topic of water environment safety of China, this paper has selected the three northeast provinces of China as the research object due to their representativeness in economic development and resource security. By using the Entropy Weight Method, the Grey Correlation Analysis Method, and the Principal Component Analysis Method, this paper has first constructed a water environment safety evaluation system with 17 indicators from the economic, environmental, and ecological aspects. Furthermore, this paper has screened the initially selected indicators by the Principal Component Analysis Method and finally determined 11 indicators as the evaluation indicators. After indicator screening, this paper has adopted the improved Fuzzy Comprehensive Evaluation Method to evaluate the water environment safety of the three northeast provinces of China and obtained the change in water environment safety of different provinces from 2009 to 2017. The results show that the overall water environment safety of the region had improved first but worsened afterward, and that in terms of water safety level, Jilin Province ranked first, followed by Heilongjiang Province and Liaoning Province. The three factors that have the greatest impact on the water environment safety of the three provinces are: Liaoning—Chemical Oxygen Demand (score: 17.10), Per Capita Disposable Income (score: 13.50), and Secondary Industry Output (score: 11.50); Heilongjiang—Chemical Oxygen Demand (score: 18.64), Per Capita Water Resources (score: 12.75), and Concentration of Inhalable Particles (score: 10.89); Jilin—Per Capita Water Resources (score: 15.75), Chemical Oxygen Demand (score: 14.87), and Service Industry Output (score: 11.55). Based on analysis of the evaluation results, this paper has proposed corresponding policy recommendations to improve the water environment safety and promote sustainable development in the northeast provinces of China.

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Pengembangan Potensi Energi Alternatif Dengan Pemanfaatan Limbah Cair Kelapa Sawit Sebagai Sumber Energi Baru Terbarukan Di Kabupaten Kotawaringin Timur

Jurnal Ilmu Lingkungan ◽

10.14710/jil.14.2.96-102 ◽

2016 ◽

Vol 14 (2) ◽

pp. 96 ◽

Cited By ~ 1

Author(s):

Yulian Mara Alkusma ◽

Hermawan Hermawan ◽

H Hadiyanto

Keyword(s):

Renewable Energy ◽

Chemical Oxygen Demand ◽

Palm Oil ◽

Oil Palm ◽

Liquid Waste ◽

Oxygen Demand ◽

Electrical Energy ◽

Palm Oil Mill Effluent ◽

Environmental Disaster ◽

Palm Oil Mill

ABSTRAKEnergi memiliki peranan penting dalam proses pembangunan yang pada akhirnya untuk mencapai tujuan sosial, ekonomi dan lingkungan untuk serta merupakan pendukung bagi kegiatan ekonomi nasional. Sumber energi terbarukan yang berasal dari pemanfaatan biogas limbah cair kelapa sawit dapat menghasilkan energi listrik yang saat ini banyak bergantung pada generator diesel dengan biaya yang mahal.Limbah cair kelapa sawit (Palm Oil Mill Effluent atau POME) adalah limbah cair yang berminyak dan tidak beracun, berasal dari proses pengolahan minyak kelapa sawit, namun limbah cair tersebut dapat menyebabkan bencana lingkungan apabila tidak dimanfaatkan dan dibuang di kolam terbuka karena akan melepaskan sejumlah besar gas metana dan gas berbahaya lainnya ke udara yang menyebabkan terjadinya emisi gas rumah kaca. Tingginya kandungan Chemical Oxygen Demand (COD) sebesar 50.000-70.000 mg/l dalam limbah cair kelapa sawit memberikan potensi untuk dapat di konversi menjadi listrik dengan menangkap biogas (gas metana) yang dihasilkan melalui serangkaian tahapan proses pemurnian. Di Kabupaten Kotawaringin Timur terdapat 36 Pabrik Pengolahan Kelapa Sawit yang total kapasitas pabriknya adalah sebesar 2.115 TBS/jam, menghasilkan limbah cair sebesar 1.269 ton limbah cari/jam dan mampu menghasilkan 42.300 m3 biogas.Kata kunci: Renewable Energy, Plam Oil Mill Effluent, Chemical Oxygen Demand, Biogass, Methane. ABSTRACTEnergy has an important role in the development process and ultimately to achieve the objectives of social, economic and environment for as well as an environmental support for national economic activity. Renewable energy source derived from wastewater biogas utilization of oil palm can produce electrical energy which is currently heavily dependent on diesel generators at a cost that mahal.Limbah liquid palm oil (Palm Oil Mill Effluent, or POME) is the wastewater that is greasy and non-toxic, derived from the processing of palm oil, but the liquid waste could cause environmental disaster if not used and disposed of in open ponds because it will release large amounts of methane and other harmful gases into the air that cause greenhouse gas emissions. The high content of Chemical Oxygen Demand (COD) of 50000-70000 mg / l in the liquid waste palm oil provides the potential to be converted into electricity by capturing the biogas (methane gas) produced through a series of stages of the purification process. In East Kotawaringin there are 36 palm oil processing factory that total factory capacity is of 2,115 TBS / hour, producing 1,269 tons of liquid waste wastewater / h and is capable of producing 42,300 m3 of biogas.Keywords: Renewable Energy, Plam Oil Mill Effluent, Chemical Oxygen Demand, Biogass, MethaneCara sitasi: Alkusma, Y.M., Hermawan, dan Hadiyanto. (2016). Pengembangan Potensi Energi Alternatif dengan Pemanfaatan Limbah Cair Kelapa Sawit sebagai Sumber Energi Baru Terbarukan di Kabupaten Kotawaringin Timur. Jurnal Ilmu Lingkungan,14(2),96-102, doi:10.14710/jil.14.2.96-102

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Analisis Air Limbah Pada Dapur Praktek di Politeknik Pariwisata Makassar

LaGeografia ◽

10.35580/lageografia.v18i1.11131 ◽

2019 ◽

Vol 18 (1) ◽

pp. 82

Author(s):

Muhammad Musawantoro ◽

Mustifa Shafany

Keyword(s):

Wastewater Treatment ◽

Laboratory Test ◽

Experimental Research ◽

Oxygen Demand ◽

Quality Standards ◽

Treatment Model ◽

Test Results ◽

Laboratory Test Results ◽

Wastewater Quality ◽

Wastewater Samples

The importance of research is to provide a description of wastewater content in Makassar polytechnics in the kitchen, through experimental research methods, by taking wastewater samples from practical kitchens, laboratory test results provide results data obtained from chemical Oxygen Demand supply, wastewater discharged directly into sewers Will not meet the requirements for wastewater quality standards. The wastewater treatment model in polytechnics is still not feasible and is not environmentally friendly, steps need to be taken to make wastewater installations.

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ANALISIS KANDUNGAN LIMBAH INDUSTRI TAHU DAN TEMPE RAHAYU DI KELURAHAN UNER KECAMATAN KAWANGKOAN KABUPATEN MINAHASA

AGRI-SOSIOEKONOMI ◽

10.35791/agrsosek.16.2.2020.28758 ◽

2020 ◽

Vol 16 (2) ◽

pp. 245

Author(s):

Febrian Sayow ◽

Bobby Vian Jhon Polii ◽

Wenny Tilaar ◽

Kojoh Deanne Augustine

Keyword(s):

Sampling Method ◽

Liquid Waste ◽

Quality Standards ◽

Quality Standard ◽

Water Sampling ◽

Raw Water ◽

Descriptive Research ◽

Sampling Locations ◽

The Government

This study aims to (1). Knowing the content and quality of Rahayu's tofu and tempe factory liquidwaste in Uner Village, Kawangkoan Sub-district, Minahasa Regency, and (2). To find out whether Rahayu's tofu and tempe factory liquid waste has exceeded the quality standard. This research was conducted for 3 months, namely in January 2020- March 2020. Sampling locations were carried out in the factory of Tahu and Tempe Rahayu Sub-district in Uner Village, Kawangkoan District, then continued with the analysis at the Manado Industrial Research and Standardization Laboratory (Baristand). This research was a descriptive research and laboratory analysis. Waste water sampling was carried out using a composite sampling method. Sampling was done in the first two places, raw water is used to make tofu and tempe in an inlet and the first was taken from the tofu factory wastewater and tempe in the sewer. Waste liquid sampling was carried out 3 times and for analysis carried out at the Baristand Laboratory to obtain data according to the parameters set in this study. The results showed that the quality of Rahayu tofu and tempe industrial liquid waste based on the analysis of BOD, COD, and TSS parameters that have been analyzed accordingly and have not passed the quality standards set by the Government. However, for the pH parameters are not appropriate and in accordance with the quality standards set by Government.*eprm*

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EVALUASI KINERJA INSTALASI PENGOLAHAN AIR LIMBAH RSD MANGUSADA KABUPATEN BADUNG

Jurnal Ilmiah Teknik Sipil ◽

10.24843/jits.2021.v25.i01.p04 ◽

2021 ◽

Vol 25 (1) ◽

pp. 30

Author(s):

Kadek Diana Harmayani

Keyword(s):

Wastewater Treatment ◽

Liquid Waste ◽

Oxygen Demand ◽

Secondary Data ◽

Total Suspended Solid ◽

Quality Standards ◽

Total Coliform ◽

Suspended Solid ◽

Ammonia Content ◽

Reference Quality

The Mangusada Regional General Hospital (RSD) as a provider of health facilities certainly produces liquid waste in every operational activity. Wastewater in the Wastewater Treatment Installation (WWTI) RSD Mangusada contains Biological Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), ammonia, total coliform, Total Dissolved Solid (TDS), detergent, oil and fat. This study aims to evaluate the performance of the WWTI as well as to determine the content in the wastewater after being treated by the IPAL RSD Mangusada according to the reference quality standards of the Governor of Bali Regulation No.16/2016 and Regulation of the Minister of Environment and Forestry of the Republic of Indonesia Number: P.68/Menlhk/Setjen/Kum.1/8/2016. The wastewater treatment system at RSD Mangusada uses a biological system. The data used in the analysis are secondary data, namely the Bed Occupation Rate (BOR) data in June 2020, the total number of beds, the average discharge of outlets in June 2020 and parameters of the quality and quantity of wastewater in the inlet and outlet of WWTI from January 2020 to July 2020. Based on the results of testing the quality and quantity of wastewater at the WWTI of RSD Mangusada outlet, the content of waste water in the outlet of WWTI is in accordance with the regulatory standards for the reference quality standards. In addition, the effectiveness of the efficiency of the WWTI at RSD Mangusada succeeded in reducing the ammonia content of 92.35%, BOD5 64.03%, COD 63.97%, TSS 67.03%, oil and fat 64.64%, total coliform 76.84%. , and detergent at 76.25%. But the efficiency of the WWTI of RSD Mangusada was not good enough in reducing the TDS content of -3.92%.

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An investigation on treatment of tannery wastewater by electrocoagulation

Global NEST Journal ◽

10.30955/gnj.000547 ◽

2013 ◽

Vol 11 (4) ◽

pp. 546-555 ◽

Cited By ~ 3

Keyword(s):

Chemical Oxygen Demand ◽

Suspended Solids ◽

Oxygen Demand ◽

Electrical Current ◽

The Other ◽

Tannery Wastewater ◽

Contact Duration ◽

A Value ◽

Removal Efficiencies ◽

Electro Coagulation

Treatability by the electro-coagulation (EC) and electro-Fenton (EF) methods have been applied to the tannery wastewater from an organized industrial region consisting mostly of tannery plants and compared with each other in this study. Iron plates were used as the anode and cathode. Electrical current was applied at a value of 33.3 mA m-2 for all processes in order to determine the electricity consumptions for chemical oxygen demand (COD) and sulfide removal. The optimal contact duration for each process was discovered at the end of the first five minutes. During the EC process, the removal efficiencies of COD and sulfide were 46% and 90%, respectively. Electricity consumptions were also obtained as 1.8 kWh kg- 1 COD removed and 27.7 kWh kg-1 sulfide removed. During the EF process, on the other hand, the removal efficiencies of COD and sulfide parameters were 54% and 85%, respectively, and electricity consumptions were also obtained as 1.5 kWh kg-1 COD removed and 8.3 kWh kg-1 sulfide removed. Furthermore, the removal efficiencies of total Chrome and suspended solids were determined to be 97% and 70%, respectively.

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Utilization of Bottom Ash Coal and Agarwood in Waste Water Treatment in Palembang Jumputan Fabric

Indonesian Journal of Fundamental and Applied Chemistry ◽

10.24845/ijfac.v6.i1.01 ◽

2021 ◽

Vol 6 (1) ◽

pp. 1-7

Author(s):

Eis Sri Hartati ◽

◽

Muhammad Hatta Dahlan ◽

Tuti Indah Sari

Keyword(s):

Activated Carbon ◽

Flow Rate ◽

Waste Water Treatment ◽

Bottom Ash ◽

Liquid Waste ◽

Oxygen Demand ◽

Quality Standards ◽

Operating Conditions ◽

Feed Flow Rate ◽

Filtration Time

Waste containing dyes causes visual pollution and increase the risk of environmental and health issue. The aim of this study was to determine the best operating conditions of jumputan liquid waste treatment using bottom ash batubara and agar wood with variations in feed flow rate (1, 2, and 3 l/min), filtration time (30, 60, 90, and 120 mins), and treatment. The results are compared with the parameters of Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), and pH of clean water quality standards for jumputan industry businesses and/or activities regulated in the Governor’s of Sumatera Selatan Regulation Number 16 year 2005. The initials analysis of jumputan liquid waste before processing showed that jumputan liquid waste did not meet these quality standards, except pH and turbidity levels. In this study, jumputan liquid waste was pretreated using coal bottom ash and activated carbon, then filtered. Biodegradation of jumputan liquid waste by conventional method. The best of BOD, COD, TSS, pH, and the percentage of color rejection in the study were obtained in the treatment of jumputan liquid waste using bottom ash batubara and activated carbon at 120 minutes filtration time and a 1 l/minute feed flow rate namely BOD 5.98 mg/l, COD 15 mg/l, TSS 22.3 mg/l, pH 7.32, color 5 Pt-Co, and 0 NTU turbidity. The filtration with bottom ash coal and agar wood can removed the coloring from dyes.

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Chemical Treatment of Liquid Waste Generated from Leather Tannery Industry by Using Alum as Coagulant Material

Materials Science Forum ◽

10.4028/www.scientific.net/msf.991.178 ◽

2020 ◽

Vol 991 ◽

pp. 178-184

Author(s):

Zainus Salimin ◽

Faldy W. Satiyoaji ◽

Dwi A. Prasetya ◽

Achmad Chafidz

Keyword(s):

Chromium Content ◽

Liquid Waste ◽

Quality Standards ◽

Trivalent Chromium ◽

Total Chromium ◽

Chromium Level ◽

A Value ◽

Leather Tanning ◽

Tannery Industry ◽

Tanning Industry

The tannery industry generally produces trivalent chromium waste (Cr3 +) and hexavalent chromium (Cr6 +). This waste before being released into the environment must meet quality standards according to KEPMENLH no.51 / MENLH / 10/1995 concerning liquid quality standards for industrial activities which says the maximum total chromium content is 0.6 ppm. This study aims to reduce the levels of Chromium in waste produced by the leather tanning industry by using alum coagulants. This research uses simulation waste which is made based on the results of BPPT analysis of waste in the leather tanning industry in Tangerang city, namely CV "Lengtat Tangerang Leather". The method used in this research is coagulation-flocculation with alum as a coagulant and lime as an alum reaction assistant in the form of hydroxide ions. The parameters observed in this study were the pH adjustment and the ratio of alum mass to lime mass. From the results of the study it was found that the decrease in the best chromium content for Cr + 3 occurred at a ratio of 5 and pH 8.2 which resulted in a chromium content of 0.0076 ppm with a decrease in percentage of 99.95%. As for the Cr6 + test, at a ratio of 3 and pH 6.4 the chromium content showed a value of 0.4110 ppm. The lowest chromium level occurs at a ratio of 5 and pH of 5.8 which results in a chromium level of 0.3341 ppm with a decrease percentage of 56.61%.

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