Dasar-dasar Reaksi dan Sifat Kimia Alam

AF AssomadiWarmadewanthi

Kuliah Kimia Lingkungan I

Hubungan antar sistem lingkungan dengan manusia dan kehidupan

Environmental Chemistry

•Is the study of the sources, reactions, transport, effects, and fates of chemical species in water, soil, air, and living environments, and the effects of technology thereon

Pertukaran Zat/Materi antar sphere

Carbon Cycle (1)

Siklus Karbon (C-Cycle)

Nitrogen cycle (2)

Siklus Nitrogen (N-cycle)

Sulfur Cycle

Siklus Sulfur(S-cycle)

Phosphorus cycle

Siklus Fosfat (P-cycle)

Beberapa impact teknologi pada lingkungan•Agricultural perubahan lahan, drainase,

irigasi, pestisida•Manufacturing polusi udara, polusi air, by-

produk limbah hazard dsb•Extraksi and produksi mineral kerusakan

lingkungan dan polusi•Produksi Energi dan penggunaannya

kerusakan lahan/tanah, polusi air (garam), emisi polutan udara (hujan asam) dsb

•Transportasi Modern automobile, perubahan struktur tanah (jalan), emisi polusi udara, peningkatan penambangan minyak dsb

technology can be applied to minimizeenvironmental impact

•maximum energy efficiency, maximum utilization of raw materials, and minimum production of pollutant by-products

•minimize pollution problems•maximum materials recycling and

minimum waste product production•advanced biotechnologies•catalysts for efficient synthesis•minimize waste production

Dasar-dasar Reaksi dan Sifat Kimia Alam

Reaksi-reaksi Kimia Air

AF AssomadiWarmadewanthi

Kuliah Kimia Lingkungan I

Sanitation Condition•Kurang dari 1% air siap pakai di dunia

yang layak digunakan.

•10 negara pengguna air terbesar : India, China, AS, Pakistan, Jepang, Thailand, Indonesia, Bangladesh, Meksiko dan Rusia

•20% penggunaan air secara global bersumber dari air bawah tanah.

1.1

•Pada tahun 2030, 47% penduduk dunia hidup dalam kelangkaan air

•Kebutuhan air sehari hari adalah 20-50 liter/org/hari yang bebas dari kontaminasi

•87% populasi dunia-5,7 miliar minum dari air olahan

•2,5 miliar orang hidup dalam sanitasi yang buruk

1.2

•Global warming - menyebabkan 2 miliar orang terkena dampak bencana dan

86% akibat banjir dan kekeringan

•Kenaikan suhu 3-4 0 C 300 orang mengungsi akibat bencana ini.

Steady StateAddition and Removal

Siklus Air(hydrologic cycle)

dalam triliun liter/hari

Air• Struktur terdiri atas 2 atom

H dan 1 atom O dalam setiap molekulnya

• Struktur bersudut 105 o moment dipol tidak nol (polar)

• Kemampuan sangat besar membentuk ikatan hidrogen (kelarutan molekul, logam, suspensi)

• Pelarut yang universal• Kapasitas panas tinggi• Densitas terbesar pada 4 oC

(jaminan kelangsungan hidup)

26

Ikatan Hidrogen

27

Water Chemistry

The polarity of water causes it to be cohesive and adhesive.

Polarity unequal charge distribution in a molecule resulting in a – region and a + region

cohesion: water molecules stick to other water molecules by hydrogen bonding

adhesion: water molecules stick to other polar molecules by hydrogen bonding

28

Water Chemistry

cohesion

29

Water Chemistry

adhesion

Sifat Air

Stratifikasi Air danau

Major Aquatic Chemical Process

Kesetimbangan CO2-CaCO3 di air

CO2 di Air

Kesetimbangan CO2 di Air

Oksidasi-Reduksi di Air

37

Properties of Water

1. Water has a high specific heat.- A large amount of energy is required to change the temperature of water.

2. Water has a high heat of vaporization.- The evaporation of water from a surface causes cooling of that surface.

38

Properties of Water3. Solid water is less dense than liquid

water.- Bodies of water freeze from the top down.

39

40

Properties of Water

4. Water is a good solvent.- Water dissolves polar molecules andions.

41

Properties of Water

5. Water organizes nonpolar molecules.- hydrophilic: “water-loving”-hydrophobic: “water-fearing”- Water causes hydrophobic molecules to aggregate or assume specific shapes.

6. Water can form ions. H2O OH-1 + H+1

hydroxide ion hydrogen ion

Ionization; happens spontaneously

KELOMPOK

1. Berdasarkan properties of water, jika temperature di dalam air naik, maka bagaimana dengan kelarutan oksigen di dalam air ? (NAIK atau TURUN)

2. Sebutkan reaksi-reaksi kimia di dalam air ? Jika suhu naik dalam air, maka bagaimana dengan kecepatan proses tersebut? (MENINGKAT atau MELAMBAT)

3. Dalam siklus biogeokimia, decomposer berfungsi untuk mendekomposisi bahan organik. Jika suhu naik dalam air, maka bagaimana dengan pertumbuhan atau perkembang biakan decomposer tersebut? (MENINGKAT atau MELAMBAT)

STANDAR BAKU MUTU

AIR BERSIH atau AIR MINUM

Fisik

• Suhu• Kekeruhan• Conductivit

y

Kimia

• pH• DO• BOD

Biologi

• E Coli• Total

Coliform

No Parameter SatuanSyarat Air Minum

*)Hasil Analisa Metode Analisa

A. FISIKA1 Bau - - -2 Total Disolved Solid (TDS) mg/L 500 Gravimetri3 Kekeruhan Skala NTU 5 Turbidimetri4 Rasa - - -

5 SuhuoC Suhu Udara Termometer

6 Warna Unit PtCo 15 Spektrofotometri

7 Daya Hantar Listrik (DHL) mmhos/cm - Conductivity meter

B. KIMIAa. Kimia Anorganik

1 Air Raksa mg/L Hg 0.001 2 Aluminium mg/L Al 0.2 AAS

3 Ammoniak mg/L NH3-N 1.5 Spektrofotometri

4 Arsen mg/L As 0.01 AAS5 Barium mg/L Ba 0.7 AAS6 Besi mg/L Fe 0.3 Spektrofotometri7 Boron mg/L B 0.5 8 Fluorida mg/L F 1.5 Spektrofotometri9 Kadmium mg/L Cd 0.003 AAS

10 Kesadahan Total mg/L CaCO3 500 Tetrimetri11 Khlorida mg/L Cl 250 Argentometri

12 Kromium, Valensi 6 mg/L Cr6+

0.05 AAS13 Mangan mg/L Mn 0.4 Spektrofotometri14 Natrium mg/L Na 200 AAS15 Nikel mg/l Ni 0.07 AAS16 Nitrat mg/L NO3-N 50 Spektrofotometri17 Nitrit mg/L NO2-N 3 Spektrofotometri18 Perak mg/L Ag 0.001 AAS19 pH - 6,5 - 8,5 pHmeter20 Selenium mg/L Se 0.01 7 Seng mg/L Zn 3 AAS

22 Sianida mg/L CN 0.07 Spektrofotometri23 Sulfat mg/L SO4 250 Spektrofotometri24 Sulfida mg/L H2S 0.05 Iodimetri25 Tembaga mg/L Cu 2 26 Timbal mg/L Pb 0.05 AAS27 Sisa Khlor mg/L Cl2 5 Iodimetri

b. Kimia Organik1 Zat Organik mg/L KMnO4 10 Oksidasi/Titrimetri2 Detergent mg/L LAS 0.05 Spektrofotometri

C. BAKTERIOLOGI1 Total Koliform MPN/100 mL 0 Fermentasi Multi Tabung2 E. Coli MPN/100 mL 0 Fermentasi Multi Tabung

*) : Per. Men.Kes. No.: 492/Menkes/Per/IV/2010 Tanggal 19 April 2010

AIR LIMBAH Efluent Standar

No Parameter Satuan Baku Mutu Air Limbah Domestik *)

Hasil Analisa

Metode Analisa

1234

pHT S SB O DMinyak & Lemak

-mg/L

mg/L O2

mg/L

6 - 910010010

pHmeterGravimetri

WinklerGravimetri

AIR PERMUKAAN Stream StandarNo Parameter Satuan

Baku Mutu Air Kelas I *)

Hasil Analisa Metoda Analisa

A. FISIKA

1 TemperaturoC deviasi 3 Termometer

2 Total Disolved Solid (TDS) mg/L 1000 Gravimetri3 Padatan Tersuspensi (SS) mg/L 50 Gravimetri

B. KIMIA1 pH - 6,0 - 9,0 pH meter2 Barium mg/L Ba 1 AAS3 Besi mg/L Fe 0.3 Spektropotometri4 Boron mg/L B 1 AAS5 Mangan mg/L Mn 0.1 Spektropotometri6 Tembaga mg/L Cu 0.02 AAS7 Seng mg/L Zn 0.05 AAS

8 Krom Heksavalen mg/L Cr6+

0.05 AAS9 Kadmium mg/L Cd 0.01 AAS

10 Raksa mg/L Hg 0.001 AAS11 Timbal mg/L Pb 0.03 AAS12 Arsen mg/L As 0.05 AAS13 Selenium mg/L Se 0.0 AAS14 Kobalt mg/L Co 0.2 AAS15 Khlorida mg/L Cl - Argentometri

16 Sulfat mg/L SO4 400 Spektropotometri

17 Sianida mg/L CN 0.02 Spektropotometri18 Sulfida mg/L H2S 0.002 Iodometri19 Fluorida mg/L F 0.5 Spektropotometri20 Sisa Khlor Bebas mg/L Cl2 0.03 Iodometri21 Total Phospat mg/L PO4-P 0.2 Spektropotometri22 Nitrat mg/L NO3-N 10 Spektropotometri23 Nitrit mg/L NO2-N 0.06 Spektropotometri

24 Amonia Bebas mg/L NH3-N 0.5 Spektropotometri

25 BOD mg/L O2 2 Winkler

26 COD mg/L O2 10 Reflux/Titrimetri

27 Disolved Oxygen (DO) mg/L O2 6 Iodometri

28 Detergent Anionik mg/L LAS 0.2 Spektropotometri29 Fenol mg/L 0.001 Spektropotometri

30 Minyak & Lemak mg/L 1 Gravimetri

*) = PP. No. 82 Tahun 2001 Tanggal 14 Desember 2001

Baku Mutu Air LautNO. TEST DESCRIPTION

SAMPLE RESULT

REGULATORY LIMIT*

UNIT METHOD

I. Physical Properties

1 Odour Odourles s - Odor SNI 06-6860-2002

2 Total Sus pended Solids , TSS

50 80 m g/L SNI 06-6989.3-2004

3 Was te - Nihil -

4 Tem perature 29 Air Tem p. ± 3 oC SNI 06-6989.23-2005

II. Chemical Properties

5 pH 7.43 6.5 - 8.5 - SNI 06-6989.11-2004

6 Salinity (NaCl) 25.3 Nature 0%

7 Free Am m onium , NH3-N <0.01 0.3 m g/L SNI 06-6986.30-2005

8 Sulfida,H2S 3 0.03 m g/L SNI 6989.70-2009

9 Phenol <0.005 0.002 m g/L SNI 06-6989.21-2004

10 Surfactants , MBAS <0.025 1 m g/L SNI 06-6989.51-2005

11 Oil and Greas e <2.7 5 m g/L SNI 06-6989.10-2004

III. Dissolved Metal

12 Mercury, Hg** <0.000002 0.003 m g/L APHA 3112 B-2005

13 Cadm ium , Cd 0.176 0.01 m g/L SNI 6989.16-2009

14 Tem baga,Cu <0.0014 0.05 m g/L SNI 6989.6-2009

15 Lead, Pb 0.2 0.05 m g/L SNI 6989.8-2009

16 Zinc, Zn 0.125 0.1 m g/L SNI 06-6989.7-2004

III. Biology

17 Total Coliform (Mem brane Filter)**

<1 1000 MPN/100m l APHA 9222 B-2005

Sumber: Hasil Monitoring Lingkungan KLHS KKJSS, 27 Juni 2012 Per MenLH No. 52 Tahun 2004

KONDISI KUALITAS AIR TANAH(sumber : Survey Kualitas Lingkungan [air, udara dan laut])

KONDISI KUALITAS AIR PERMUKAAN(sumber : Survey Kualitas Lingkungan [air, udara dan laut])

PLANKTON & BENTHOS PERAIRAN LAUT(sumber : Survey Kualitas Lingkungan [air, udara dan laut])

Menunjukkan kadar nutrient di laut sangat tinggi seperti konsentrasi nitrogen dan phosphatPENCEMARAN DARI AIR PERMUKAAN

Produktivitas laut tinggi dan tidak ada pencemaran akibat pestisida

Skeletonema

Pseudo-nitzchia

Thalassionema Nitzchioides

Larva naupulius cirripedia

Larva Brachyura

Water Quality ParametersTemperature - Dissolved Oxygen (DO) - pH

Alkalinity - HardnessNitrates and Phosphates - Turbidity

Conductivity-

Temperature

Affects:Water densityThe solubilityChemical reaction ratesOrganism growth ratesConductivitypHDissolved Oxygen

Contoh : Jika CuO, di dalam air dengan suhu 250C mempunyai log Kso = 10 7.644 dan entalphy adalah -15.504 kcal/mol atau – 64.90 kJ/mol. Berapa solubility dari CuO jika temperature di dalam air turun 10oC

TEMPERATURE NAIK, SOLUBILITY AKAN MENURUN DAN VISE VERSA

Q10 rulecold-blooded aquatic organisms

Predicts that growth rate will double if temperature increases by 10˚C (18˚F) within their "preferred" range.

Gases Dissolve in Water

Oksigen di Air

•O2 dibutuhkan terlarut di air untuk menjaga reaksi oksidasi-reduksi, respirasi, degradasi dst

•Kelarutan O2 di air tergantung temperatur, pd 25 oC sekitar 8,5 mg/L; pada 0oC 14,74 mg/L

•Dihasilkan dari proses fotosintesis alga/tumbuhan hijau di air dan proses aerasi

Henry’s Law

Henry’s Law Constant

For example, oxygen is 20.95% of theair on a molar basis and, therefore, PO2 is 20.95% of the atmospheric pressure,or 0.2095 atm under standard conditions.]

BAGAIMANA KELARUTAN OKSIGEN JIKA TEMPERATURE NAIK ?

Suhu 15oC dan 20oC

Dissolved Oxygen (DO)DO is the measurement of oxygen dissolved in water and available for fish and other aquatic life.

Indicates health of an aquatic system.

Can range from 0-18 ppm.

Most natural water systems require 5-6 ppm to support a diverse population.

Varies with time of day, weather, temperature.

Dissolved Oxygen (DO)Increase in organic waste

Increase in algae/plant vegetation

Decrease in DO available to organisms

Leads to changes in ecosystem asorganisms needing lots of DO are replaced by organisms needing little.

Self Purification

pH - p(otential of) H(ydrogen)

Determines the solubility of nutrients (PO4-3, NO3

-, C) and heavy metals (Fe, Cu, etc)

Determines availability of these chemicals for use by aquatic life.

In natural water systems, determined largely by geology and soils.

pH of natural waters

due to humic acidLimestone, marble, CO3 rich

Pure rain, snow

Sea water

Factors that affect pH• Algal blooms • Bacterial activity • Water turbulence • Chemicals flowing into the water body • Sewage overflows • Pollution

How pH affects aquatic life

Decreasing pH (e.g.: via acid rain)

▼Liberation of Al, metals

▼Toxic conditions

▼Chronic stress

▼Smaller, weaker fish

Alkalinity

Alkalinity refers to the capability of water to neutralize acid.

Buffering capacity – resistance to pH changes.

Common natural buffer: CO3 (carbonates – like limestone).

Protects aquatic life.

Commonly linked to water hardness.

In natural systems: 50 – 150 mg/L as CaCO3.Limestone outcrop

Hardness

Reflects dissolved carbonate minerals.

Mostly of concern for drinking water standards.

Metals precipitate out of solution.

Create scale/hard water deposits

High alkalinity Hard water

andNitrate (NO3

-) naturally-occurring form of nitrogen found in soil.

Forms by microbial decomposition of fertilizers, plants, manures or other organic residues

Plants uptake nitrates (Spinach a good source).

Phosphate (PO4-3)

naturally occurs in rocks and minerals.

Plants uptake weathered-outelements and compounds.

Animals ingest plants.

Water soluble.

Redfield Ratio: 106:16:1

Nitrates

The U.S. EPA has set a maximum contaminant level for NO3

- in drinking water of 10 parts per million (ppm)

Artificial sources:• Livestock manure/urine• Failing septic systems• Synthetic fertilizers

Can lead to:eutrophication of natural water systems (overproduction of vegetation)

Blue baby syndromne

Artificial sources:• Sewage• Laundry,

cleaning fluids• Synthetic

fertilizers

Can also lead to eutrophication of natural water systems (overproduction of vegetation)

Phosphates

Blue green algae

1990 and 1999 comparison of Nitrates in Great Lakes

From US EPAhttp://www.epa.gov/glnpo/monitoring/limnology/SprNOx.html

Solutions??

Wetland restoration Reduce fertilizers

Reduce emissions – WWTP/industryReduce soil erosion

Turbidity

Measures how “murky” the water is

Estimates:

Mineral fractionOrganicsInorganicsSoluble organic compoundsPlanktonMicroscopic organisms

MODIS Image from NASAhttp://rapidfire.sci.gsfc.nasa.gov/

Causes of highly waters

• In open waters, phytoplankton• Closer to shore, particulates

Resuspended bottom sediments (wind)

• Organic from stream and/or wastewater discharges.

• Channelization• Increased flow rates• Too many bottom-feeding fish

(such as carp)

Effects of highly waters

• Modify light penetration• Increase sedimentation rate• Smother benthic habitats • Settling clay particles• Fine particulate material also can damage sensitive structures • Decrease organism resistance to disease• Prevent proper egg and larval development• Macrophyte growth may be decreased• Reduced photosynthesis can lead to lower daytime release of oxygen

ConductivityAbility of a substance to conduct an electrical current.

In water, conductivity determined by types and quantities of dissolvedsolids. (Commonly called Total Dissolved Solids = TDS)

Current carried by ions (negatively or positively charged particles).

Eg: NaCl(aq) = Na + + Cl –

Cl-Na+Na+

Na+

Na+

Na+ Cl-

Cl-

Cl-

Cl-

Na+Cl- Cl- Cl- Cl-

Na+Na+ Na+Na+ Na+Na+ Na+Na+

Cl- Cl- Cl- Cl-

Na+ Na+ Na+Na+

Cl- Cl- Cl- Cl-

Na+ Na+ Na+Na+

Cl- Cl- Cl- Cl-

Na+ Na+ Na+ Na+Na+

Na+Na+

Na+ Na+

Na+ Na+

ConductivityConductivity of natural waters depends upon:

Ion characteristics (mobility, valence, concentration)

Water temperatureGeologySize of watershedEvaporation

Some artificial factors that can affect conductivity:WastewaterUrban runoff (especially road salt)Agricultural runoff

The most abundant components of a kilogram of seawater.

The Components of Salinity